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Part IX. Pests and Diseases of Plants

Sprays and Poisons for Insects[1].

Spraying for insect pests has become a very important factor in the growing of a large number of crops and especially in horticultural work. As such it is now a regular and well established business which has received a very large amount of investigational work, with the result that there are today efficient sprays for most of the important ailments a tree or plant is heir to. This is true of both the home-made and commercial products, and it is often an exceedingly difficult task to select a preparation or formula which will give the best results for the outlay of money. It is the desire of the writer to give the formulae and methods of preparation of some of the most important which can be made at home or the equivalents of which may be obtained from commercial manufacturers.

In general insecticides, whether they be liquids, solids or gases, are usually listed in three main classes, viz: arsenical, contact and repellent. The arsenical sprays are used in controlling biting and chewing insects which are capable of taking the poison internally. They are the cheapest and therefore used wherever practical. The contact sprays are for piercing and sucking insects as well as biting and chewing insects which can not be controlled by arsenicals. The gases and repellents are used for all classes of insects; the gases kill directly and the repellents, being distasteful, prevent or repel attacks.

Arsenical Insecticides.

Paris green and London purple were the first arsenicals used as insecticides, but of late years it has been discovered that lead arsenate and zinc arsenite, while not quite as strong, are much less liable to damage the fruit and foliage and have therefore largely replaced the stronger arsenicals. Paris green, however, is still used for certain insects, and where there is no danger to foliage as in the use of baits, it is used very largely. White arsenic is also used for this purpose and is much less expensive.

Arsenicals are largely used in combating such insects as grasshoppers, armyworms, cutworms, caterpillars, slugs, beetles, or any others which actually eat the foliage or fruit.

Lead Arsenate.

There are two kinds of lead arsenate on the market - the ordinary, or acid, which is generally used and at times causes severe burning to fruit and foliage if applied too strong, and neutral lead arsenate, which is perfectly safe and should be used wherever there is any danger of burning tender fruit and foliage, or usually in combination when other insects or fungi are to be sprayed at the same time.

A. Lead arsenate (paste) 4 to 8 pounds

Water 100 gallons
B. Lead arsenate (powder) 2 to 8 pounds

Water 100 gallons

Mix the paste or powder in the required amount of water or first in a small amount and add the remainder for use. See that the mixture is thoroughly agitated when spraying in order to keep the lead arsenate in proper suspension.

Lead arsenate is rendered none the less effective when combined with Bordeaux mixture, iron sulfid or tobacco decoctions, but the acid type should never be used in combination with oil emulsions, soap sprays and doubtfully with lime-sulphur. The neutral type, however, may be used safely with any of the above.

Paris Green.

If lead arsenate can not be had, Paris green may be used as follows:

Paris green
1 pound
Air-slaked lime (or better, dry water-slaked lime) 5 pounds
Water 200 gallons

First stir the poison into a thin paste with a little water, add this to the lime, then strain the mixture through a sieve into a tank containing the required amount of water. It is particularly necessary to keep this mixture well agitated while spraying.

As a dust, Paris green is mixed as follows:

Paris green 5 ounces
Air-slaked lime 1 pound

The Paris green and lime are thoroughly powdered, mixed and dusted upon the plants through a muslin hag or by means of a blower.

Paris green may be effectually used when combined with Bordeaux mixture, but should never be applied in combination with lime-sulphur, soap sprays and emulsions.

Poison Baits.

Poison baits occupy a very important place in the control of certain insects, such as grasshoppers, armyworms, cutworms, wireworms, etc., and are especially useful to the small gardener, though they have often been used with excellent results in large fields and orchards.

Poison Bran Mash.

No. 1. Bran 25 pounds

Paris green 1/2 pound

Cheap molasses 1 quart
No. 2. Bran 40 pounds

White arsenic 5 pounds

Molasses 2 gallons

In preparing these mix the arsenic or Paris green and bran dry, and add the molasses, which has been diluted in water. Add enough more water to moisten the bran so that it will appear between the fingers when the mixture is squeezed in the hand.

Some prefer to moisten the bran first and afterward stir in the molasses and poison.

Criddle Mixture.

This mixture is exceedingly cheap and effective, especially for grasshoppers.

Fresh horse dung 60 pounds
Common salt 2 pounds
Paris green 1 pound

The Paris green is mixed with enough water to form a paste and is then stirred thoroughly into the horse dung with the salt.

These poisoned baits are scattered about in fields infested with grasshoppers, armyworms, cutworms and various other destructive chewing insects, or they may be placed in advance of the oncoming hordes. A very important thing is to see that the poisoned baits are kept moist, as they become worthless when dry. To prevent this drying out the mixture should be put out in small piles and occasionally moistened. They may also be placed under boards or in the shade, while for cutworms and wireworms it is often advisable to bury them in the ground.

Citric Bran Mash.

A mash recommended by S. T. Hunter and P. W. Claassen has been used in this State very successfully to combat grasshoppers. The formula is in two parts as follows:

Part I. White arsenic (or Paris green) 2 pounds

Bran 50 pounds

Mix these dry.
Part II. Lemons (chopped fine, including rind) 1/2 dozen

Syrup or molasses (cheap) 4 quarts

Water 5 gallons

Mix these together.

Mix Part I and Part II and add enough water to make a wet mash. The parts should not be mixed until ready for use. Distribute broadcast in front of the pests early in the morning.

Contact Insecticides - Liquids.


Lime-sulphur is easily the most important insecticidal spray now used, and its fungicida! properties make it even more useful to the orchardist. It is especially valuable for controlling scale insects, the peach twig-borer and fungi on deciduous fruit trees, though if properly weakened it may also be used as a summer spray, particularly for the red spiders and mites.

Formerly lime-sulphur spray was a home-made product, but today the commercially prepared product is so much more convenient than the home-made mixtures and as good as the best that can be made on the farm that the use of the latter has almost ceased.

Home-Made Lime-Sulphur.

Stone lime 50 pounds
Sulphur, flowers of 110 pounds
Water to make 50 gallons

Heat in a cooking barrel or vessel about one third of the total quantity of water required. When the water is hot, add all of the lime, and at once add all the sulphur, which should previously have been made into a thick paste with water. After the lime is slaked, another third of the water should be added, preferably hot, and the cooking should be continued for an hour, when the fina! dilution may be made, using either hot or cold water as is most convenient. The boiling due to the slaking of lime thoroughly mixes the ingredients at the start, but subsequent stirring is necessary if the wash is cooked by direct heat in kettles. After the wash has been prepared it must be strained through a fine sieve as it is being run into the spray tank. The resultant product is a concentrated solution of lime-sulphur, which should be diluted for use as directed in the table for diluting the commercial lime-sulphur, which follows.

Commercial Lime-Sulphur.

The commercial lime-sulphur is a perfectly clear liquid needing only to be diluted for use. Because of its dependency it is fast replacing the home-made preparations. There are three common brands upon the market in California under the trade names "Rex," "Ortho" and "Orchard," though there are many other brands which may be obtained elsewhere.

In using the lime-sulphur it is very important to have just the right amount of dilution. This is ascertained by the use of a Baumé hydrometer. The following table shows the dilutions for dormant and summer spraying with lime-sulphur mixtures:

Amount of Dilution. Number of Gallons of Water to One Gallon of Lime-Sulphur Solution
Reading of Hydrometer (Baumé) For Winter Spraying For Summer Spraying
36 Degrees 11 46 3/4
35 9 45
34 8 3/4 43 1/4
33 8 41 1/2
32 8 40
31 7 1/2 37 1/4
30 7 1/4 36 1/4
29 6 3/4 34 1/4
28 6 1/2 32 3/4
27 6 31
26 5 3/4 29 1/2
25 5 1/4 27 3/4
24 5 26
23 4 1/2 24 1/2
22 4 1/4 22 3/4
21 3 3/4 21 1/4
20 3 1/2 19 3/4
19 3 1/4 18 1/4
18 3 17
17 2 3/4 16
16 2 1/2 15
15 2 1/4 14

Lime-Sulphur and Flour Paste.

For spraying trees in foliage and tender plants a lime-sulphur flour paste spray has given remarkably good results. The following formulae are recommended:

No. 1. Water 200 gallons

Flour paste, 8 pounds flour in 8 gallons water

Sublimed sulphur 10 pounds

Lime-sulphur solution 2 1/2 gallons

The flour is first made into a thin paste by adding one pound to each gallon of water, according to the above formula. The sulphur is made into a paste also and added with the flour paste and lime-sulphur solution to the two hundred gallons of water in the spray tank. This spray is excellent for the red spiders on almond and citrus trees. Minus the lime-sulphur solution it is a very effective spray for the two-spotted mite on hops.

No. 2. (Iron Sulphide.) Water 200 gallons

Flour paste, 8 pounds flour in 8 gallons water

Lime-sulphur solution 2 1/2 gallons

Iron sulphate 4 pounds

This spray is mixed as the preceding, and the iron sulphate after being dissolved is added directly to the diluted mixture in the tank.

The above spray is especially recommended for late summer sprayings for red spider on almond and citrus trees, but should not be applied to fruit trees just before the fruit is ready to pick, as the fruit might be stained.

For "self-boiled" lime sulphur see page 228.

Lime-sulphur may be used in combination with tobacco sprays and applied with safety on citrus trees prior to fumigation. It should not be combined with Paris green, acid lead arsenate, zinc arsenite, oil emulsions and soaps. With neutral lead arsenate, however, no damage may result.

Emulsions and Miscible Oils.

Emulsions are oil sprays in which soap is most frequently used as an emulsifying agent. They have a high power of penetration and a rapid and even distribution over the sprayed surface. With ordinary care they may be readily made at home and are very valuable as insecticides.

In the miscible oils the emulsifier is incorporated in the oil. The proportions must be very exact and vary according to the variation in the composition of the oil and other ingredients, and is therefore not practical to be made at home. The miscible oil sprays are the highest type of emulsions and are almost universally employed for commercial purposes.

Kerosene Emulsion.

There are two general types of kerosene emulsion, as follows:

Cook Emulsion. - In this emulsion there is a larger amount of soap. It is the easiest to make, slightly more expensive and usually about as effective if made with a good grade of fish oil soap. The general formula is:

Fish oil soap 1 pound
Kerosene 1/2 gallon
Water 2 gallons

This was the first attempt at making an emulsion of this type and was a great discovery in insect control. It was invented by Dr. A. J. Cook when at the Michigan Agricultural College.

Riley-Hubbard Emulsion. - In this emulsion the proportion of soap does not vary far from 1/4 pound to a gallon of oil. It requires very vigorous agitation, the oil going quickly into the creamy condition of the Cook emulsion, but after further agitation it thickens into a clabber-like material. The formula is:

Fish oil soap 1/2 pound
Kerosene 1/4 gallon
Water 1 gallon

Preparation. - The preparation of both of the above emulsions is about the same and consists in first dissolving the soap in the hot water, after which the kerosene is added and the whole thoroughly and vigorously agitated by pumping it into itself until a thick creamy liquid results. Soft water should be used wherever possible, as it is almost essential to obtaining a proper emulsion.

For use on dormant trees and plants in the winter dilute the stock solution one to five of water. On trees or plants in foliage dilute with ten parts of water.

Distillate Emulsion.

Distillate (28 degrees Baumé) 20 gallons
Whale oil soap 30 pounds
Water to mix 12 gallons

Dissolve the whale oil soap in the water, heating it to the boiling point; add the distillate and agitate thoroughly while the solution is hot. For use add twenty gallons of water to each gallon of the above mixture.

Carbolic Acid Emulsion.

Whale oil soap 40 pounds
Crude carbolic acid 5 gallons
Water to mix 40 gallons

Dissolve the soap in hot water (the soap must be entirely dissolved) add the carbolic acid and heat to the boiling point for twenty minutes (reserve some water to add in case the mixture begins to boil over). For use add twenty gallons of water to every gallon of the above stock solution. The emulsion needs little or no agitation.

This spray is especially recommended for mealy bugs, but is also suitable for plant lice and soft brown scale. It is also a good contact insecticide for ants.

Crude Oil Emulsion.

Water 175 gallons
Liquid soap 3 gallons
Crude oil (21°-24°) 25 gallons

Fill the spray tank with the 175 gallons of water; add the liquid soap; agitate thoroughly for one minute, after which add the crude oil, continuing the agitation.

If the liquid soap can not be had, use twenty pounds whale oil soap, dissolve in ten gallons of boiling water, to which three pounds of lye have been added.

During the spraying operation this mixture should be thoroughly agitated and great care taken to wet all of the twigs. From eight to fifteen gallons should be used on a tree. The application should be made from November to February.

The crude oil emulsion is especially recommended for black scale, European fruit Lecanium, European pear scale, cherry scale and other scales infesting deciduous fruit trees. It should be applied in the winter, when the trees are dormant.

To also kill moss or lichens on fruit trees add two pounds of lye to the formula of the stock solution.

Distillate Oil Mechanical Mixture.

Water 200 gallons
Caustic soda (95 per cent) 7 pounds
Distillate (28 degrees Baumé) 10 gallons

Fill spray tank with the required amount of water; add the distillate and caustic soda, which has been dissolved in a small amount of water. Keep agitator going rapidly while applying the spray.

This spray has been thoroughly tested by the writer and is one of the cheapest and best for spraying black scale or the European fruit Lecanium on apricot and olive trees.

Distillate Emulsion and Tobacco.

Water 12 gallons
Whale oil soap 30 pounds
Distillate (32° to 34° Baumé) 20 gallons

This is the "Government Formula for Pear Thrips." The emulsion is prepared in the ordinary way as a stock solution. For use in the orchard dilute one to twenty parts of water. To every two hundred gallons of this diluted spray add one pint of tobacco extract containing forty per cent nicotine or about three and one half gallons of tobacco extract containing two and three-quarters per cent nicotine. This spray is especially recommended for pear thrips.

Rosin Wash.

Though not a true emulsion and fast losing prominence as a spray, this wash is included here because of its value as a spray and dip for plants with tender foliage.

Rosin 10 pounds
Caustic soda (76 per cent) 3 pounds
Fish oil 1 1/2 pounds
Water 50 gallons

Put oil, rosin and a gallon of water in an iron kettle and heat until the rosin is softened; add the caustic soda (dissolved in a small amount of water) and stir thoroughly, after which add enough water to make fifty gallons of spraying material.

This wash is only effective for young scale insects, plant lice, or other soft-bodied insects.

Soap Washes.

A simple and easily prepared spray for use in small gardens is made from soap as follows:

Whale oil or hard laundry soap 1 pound
Water 5 gallons

The soap is first dissolved in a small amount of hot water and the remainder added afterward. This spray will not injure tender plants or foliage, and is recommended only for young scale insects, plant lice and other soft-bodied insects.

Soap Powder.

Among the recent commercial insecticides is a soap powder which readily dissolves in hot or cold water and has very good insecticidal powers. The amount of dilution varies with the product, but is usually one pound to five or six gallons of water or as stated on the container.

Tobacco Decoctions.

For soft-bodied insects in greenhouses, conservatories, or on house plants, as well as for plant lice, leaf-hoppers and other similar insects in the open, the tobacco decoctions are invaluable because they do not injure the foliage and give excellent killing results. For home-made extract, take:

Tobacco leaves or stems 1 pound
Water 4 gallons

Steep the tobacco in the hot water and apply directly.

The commercial extracts containing two and three-quarters per cent nicotine should he diluted to sixty parts of water. The extract containing forty per cent nicotine should be diluted from one to one thousand parts or one to fifteen hundred parts of water.


A number of valuable insecticides are applied dry as dusts. We have already referred to Paris green and lime as being used in this way. Dusts are easy to mix and handle and are often of great service to the farmer and orchardist.

Flowers of Sulphur.

For a number of years flowers of sulphur was used alone as a remedy for mites on citrus and almond trees. It was distributed over the trees by hand or with a blower in the early morning when the foliage was damp, thus enabling it to adhere. The warm sunshine volatilizes some of the sulphur and oxidizes a part so as to liberate two gases, which are killing factors. Accordingly sulphur is of little avail in the cool summer weather of the coast counties or during the winter months anywhere. However, in the warm interior districts this is still a very effective remedy for mites.

Sulphur and Lime.

Even better than sulphur alone is hydrated lime and flowers of sulphur mixed in equal parts and blown upon the trees with a power machine. In the citrus orchards this is a very important method of controlling the citrus red spider and the two-spotted mite.

Lime, Sulphur and Sal Bordeaux.

This mixture is prepared as follows:

Hydrated lime (dry, finely powdered, water-slaked lime). 40 pounds
Flowers of sulphur 5 pounds
Sal Bordeaux (a mixture of bluestone, charcoal and naphthol) 5 pounds

Mix these ingredients thoroughly and apply with a power blower. This is one of the most efficient preparations now being used in controlling the red spider of deciduous trees.

Milled Sulphur.

This is sulphur to which something else is added to make it possible to grind it exceedingly fine. It is known by the trade names, atomic sulphur and diatomic sulphur. It is very good for red spider and mites.


This is commonly known as Persian or Dalmatian insect powder, or Buhach, and comes as a finely ground yellow powder with a pleasant, rather pungent odor. Unfortunately it is not only expensive but quickly loses its effectiveness when exposed to the air. Its practical range is therefore limited, and it is chiefly used on house plants, in the conservatory and in the garden. It is entirely harmless to vegetation of all kinds and does not spot or mark even the most delicate flowers when used dry. It acts a little more promptly and effectively if applied to the insects while they are moist, or at least damp. If the dusty appearance is objectionable, a decoction may be made by steeping one ounce in one quart of boiling water, and then adding two or three quarts of cold water. Into this material potted plants may be dipped, or it may be applied with an atomizer. For plant lice on house plants this makes a very clean and effective application.


Powdered white hellebore has been used for many years as a specific remedy against "currant worms," "rose slugs" and other saw-fly larvae, and is very effective, either dusted on as a powder, or in the form of a decoction. When applied, it may be used pure, or it may be mixed with two or three times its own weight of dust, cheap flour, lime, or almost any other light, finely powdered material. When used as a spray, steep one ounce in one quart of boiling water and add another quart of cold water when ready to apply.

It is also quite effective against certain root maggots, like those affecting cabbage and cauliflower. For these it is used in the form of a decoction, one ounce in one gallon of water and about half a pint poured around an infested plant, from which the earth has been drawn away to facilitate soaking directly around the plant. To be effective, the material must be brought into direct contact with the insects. Hence, it should be liberally used and applied before the maggots get down too far, or into the plant too deeply. In the garden its use is quite practical; in the field it has not been found so satisfactory.


It is apparent that certain materials, applied to the foliage of plants, are somewhat repulsive to some insects. One of the most important of these repellents is the well known fungicide, Bordeaux mixture.

Bordeaux Mixture.

The formula and method of preparation and use are given on pages 226 and 227. As an insect repellent it is used for the flea-beetles, cucumber beetles, diabrotica, and other leaf-eating insects.

Bordeaux mixture may be used in combination with Paris green, lead arsenate (acid and neutral), calcium arsenite and in some instances with rosin soap for special purposes, but should not be combined with tobacco or used prior to fumigation.


To prevent insects from crawling up the trunks of trees and plants various bands have been devised which have proven exceedingly successful in many instances.

Tangle foot. - Tree tanglefoot is a thick, sticky substance which, when applied as a band, remains moist for several weeks and is a very effective barrier against cankerworms, caterpillars, cutworms, Fuller's rose beetle and other crawling insects. The material is put up in cans. It should be applied directly to the trunk of the tree several feet above the ground.

Sticky Rope. - In the work on the California tussock moth, W. H. Volck recommends the use of rope bands saturated in an easily prepared mixture as follows:

Castor oil 1 gallon
Rosin 16 pounds

The rosin and castor oil are gently heated until the former is completely melted. If too thick more oil may be added. The bands dipped in this mixture should be replaced by new ones about every ten days. Crude oil rich in asphaltum or a mixture of equal parts of pine tar and molasses have also given satisfactory results.

Cotton Bands. - Bands of loose cotton fastened around the trunks of the trees are excellent in preventing the ascent of insects.

Oiled Paper. - Oiled paper tied around the trunks of small vines and plants is an old method which sometimes proves practical today.


Besides being used as a direct insecticide in many cases whitewash is often used indirectly to protect the trees against sunburn and thus ward off attacks of borers which seek entrance at any weakened place. There are many formulae for preparing this mixture, two of the more important of which are given below. First, ordinary whitewash:

Water 2 gallons
Quick lime 10 pounds

The lime is placed in a pail and the water added, after which the pail is covered with a couple of canvas sacks or heavy material and allowed to stand for an hour. If the lime is transparent and lumpy it has been scorched, due to the lack of sufficient water. After slaking add enough water to bring it to a brush consistency.

A more durable weatherproof whitewash is prepared as follows:

(1) Quick lime 62 pounds

Water (hot) 12 gallons
(2) Common salt 2 pounds

Sulphate of zinc 1 pound

Water (boiling) 2 gallons
(3) Skimmed milk 2 gallons

Slake the lime thoroughly in (1); dissolve the salt and sulphate of zinc in two gallons of water (2); pour (2) into (1) and add (3). Mix thoroughly. Two pounds of flour paste (dissolved in two gallons of hot water) may be added instead of the skimmed milk.


Fumigation consists in the generation and uses of gases to kill pests. Formerly such practices were limited to the uses of carbon bisulfid, sulphur dioxid and tobacco fumes. The use of hydrocyanic acid gas in citrus orchards has lately been so perfected as to become of very great importance and has opened up a remarkable field in the control of orchard pests.

Carbon Bisulfid.

Carbon bisulfid is a liquid which evaporates into a heavy, highly inflammable and explosive gas. It was first used for fumigating beans, grains or cereals for weevils, and is still a very efficient method of controlling such pests. In handling the liquid great care should be taken to keep it away from a flame on account of the vapor being highly explosive.

For Storehouse Pests. - Before fumigation is begun care should be taken to see that the room or container is made as tight as possible. The temperature should be 70 degrees Fahrenheit or above, for poor and unsatisfactory results are sure to follow even excessive doses at a lower temperature. In a tight compartment five pounds of carbon bisulfid to every 1,000 cubic feet of air space will give excellent results in killing weevils. If the compartments can not be made tight, increase the amount of the fumigant.

For Root Pests. - Carbon bisulfid has also been used in the fields to kill root pests like the woolly apple aphis, black peach aphis, grape phylloxera, white grubs, root-maggots, but is far too expensive to be practical and is effective only in soils of just the right degree of porosity. For a small plant, a hole is made in the ground near the base and a teaspoonful of the liquid poured into the hole, which is covered to prevent surface evaporation. For larger plants several holes are made deep enough to allow the vapor to disseminate around the infested roots. A syringelike instrument is sometimes used to inject the liquid into the soil around the roots of the infested plants. In all such work care must be exercised in making the applications or the plants may be killed by an excessive dose or by the carbon bisulfid coming in direct contact with the roots.

For Wood-Borers. - Carbon bisulfid is also injected into the burrows of wood-boring insects with some success, but this method has never met
with much favor, perhaps because in many cases the burrows are open only after the damage has already been done and the insects escaped.

For Ants' and Wasps' Nests. - A small amount of carbon bisulfid poured into the underground nests of ants, wasps, yellow jackets and other insects of like habits will usually exterminate the colony. This method, however, is of little avail against the Argentine ant, because of the many small nests.

Tobacco Fumes.

For very tender house and greenhouse plants infested with plant lice, thrips and other small insects or mites, it is sometimes advisable to fumigate them with slowly burning tobacco, to avoid injury to the foliage, but even in such cases hydrocyanic acid gas, if properly handled, is much better and is gradually replacing the tobacco punk and other commercial fumigants of a similar nature.

Hydrocyanic Acid Gas.

Hydrocyanic acid gas is usually generated by the addition of cyanide to diluted sulphuric acid. The generation is made in an earthenware jar, or in a special fumigating machine, the gas being confined in a fumigating house, or, as is more often the case in California, in a tent thrown over a tree. Any one desiring to use this form of fumigation should apply to C. W. Woodworth, Professor of Entomology, Berkeley, for detailed publications.

Fungous Diseases and Fungicides[2].

Professor R. E. Smith of the University of California points the purposes of fungicides in this way: "It should be clearly understood that all control of plant diseases by spraying, dipping, disinfecting, etc., must be accomplished entirely by prevention rather than cure. In other words, these fungicides, to be effective, must be applied for the purpose of poisoning and killing the spores or germs of the parasites and thus preventing their further spread and development."

Bordeaux Mixture.

Bordeaux mixture continues to be the most generally used of all fungicides. Its effectiveness and harmlessness to plants depends upon care used in its manufacture, on condition of atmosphere and of plant. The formula ordinarily used, the 5-5-50, is entirely harmless when the plant is dormant. It may also be used on some growing plants; others it will kill or greatly injure. It may be used even stronger than the formula given when the plant is dormant, but these proportions are effective with most fungous troubles. By the 5-5-50 formula is meant:

(a) Copper sulphate 5 pounds

Stone lime 5 pounds

Water 50 gallons

The weaker solution is:
(b) Copper sulphate 3 pounds

Stone lime 5 pounds

Water 50 gallons

If hydrate of lime is used add one-fourth more.

To mix, dissolve the copper sulphate with water in proportion of one pound of sulphate to sufficient water to make one gallon of solution for each pound of sulphate used. The stone lime may be slaked and dissolved in water in the same proportions as the sulphate. This gives convenient stock solutions, every gallon of which contains one pound of lime or of sulphate. To make the mixture from these stock solutions take, say, five gallons of the lime solution which will contain five pounds of stone lime, and five gallons of the sulphate solution which will contain five pounds of copper sulphate. Five gallons of each of these two solutions may now be mixed with water by pouring through a strainer into water sufficient to make fifty gallons. Do not mix the solutions before pouring into the water.

Bordeaux Paste.

The latest and best cure for gum disease recommended by Mr. Fawcett:

Blue stone 1 pound
Fresh burned lime 2 pounds

Dissolve the blue stone in one gallon water, using wooden or earthen vessel by hanging it in the top of a sack; slake the lime in about one-half gallon of water. Stir together when cool, making a mixture about the consistency of whitewash. Apply with a brush. This may also be applied to healthy bark as a preventive against new infections. Mix fresh each day or two, as mixed paste deteriorates rapidly.

Ammoniacal Copper Carbonate.

Copper carbonate 5 ounces
Ammonia (26° Baumé) 3 pints
Water 50 gallons

The strong ammonia, which must be handled carefully, may be diluted to about five times its volume, and the copper carbonate may be rubbed up with water in a small vessel to form a thin paste. Add this paste to the dilute ammonia by constant stirring. Then add water sufficient to make fifty gallons. Use as promptly as possible owing to rapid evaporation of ammonia.

Potassium Sulphide.

Potassium sulphide 6 ounces
Water 100 gallons

This is employed when coloring of foliage is not desirable.

Copper Sulphate.

Copper sulphate 1 pound
Water 15 gallons

For use on dormant trees or for disinfecting seeds copper sulphate without lime may be employed. The stock may be mixed as for Bordeaux. On growing plants it may be used with a reasonable degree of safety at the rate of one pound to 100 gallons of water.

Corrosive Sublimate.

Corrosive sublimate 2 ounces
Water 15 gallons

Corrosive sublimate or bichloride of mercury, one of the deadliest of poisons to animal life, is a very effective disinfectant and fungicide. It is one of the best preventives of potato scab. This is one of the solutions used after pruning for antiseptic dressing of wounds of trees affected with blight. It should be made and kept in wooden or earthen vessels.


Formaldehyde vapor dissolved in water in what is usually called the 40 per cent solution is one of the best fungicides and is often used in place of corrosive sublimate. It is also used for treating seed potatoes, oats and wheat. It should be employed in strength of:

Formalin 1 ounce
Water 2 gallons

Flowers of Sulphur.

Flowers of sulphur (use high-grade) is effective on surface mildews when dusted over the plant when leaves are moist. Sulphuric acid 1-1000 has also proven successful on rose mildew and similar fungi. Likewise milled sulphur.

Self-Boiled Lime-Sulphur.

Flowers of sulphur 8 pounds
Lump lime 8 pounds
Cold water 50 gallons

Place the lime and sulphur together in a barrel and add just enough cold water to slake the lime, stirring constantly to prevent burning. Keep a piece of old carpet or burlap sack over the top of the barrel to retain all the heat possible. Watch the mixture carefully and as soon as an orange colored liquid starts to gather on the surface add the rest of the water. Strain through a fine sieve to remove the particles of lime, but work all the sulphur through.

Do not use hot water or allow the mixture to stand after the lime is slaked and before dilution. In this spray we do not want the soluble sulphides (orange colored) to form, for these will injure the foliage and fruit.

Treatments for Pests and Diseases[3].

Apples, Pears and Quinces.

Aphis, Green. - Apply lime-sulphur just before buds open, if orchard has been badly infected in past years. Apply kerosene emulsion or tobacco washes as soon as the insects make their first appearance.

Aphis, Leaf-Curling. - Lime-sulphur plus Black Leaf 40, one pound to 100 gallons. Apply when the buds are beginning to open, pink showing in a few blossoms; spray very thoroughly.

Aphis, Woolly. - Spray with kerosene emulsion or tobacco washes whenever this pest appears above ground. Use at least 200 pounds pressure. For underground forms remove soil until upper roots are exposed at the base of the tree. Pour several gallons of tobacco wash around crown and replace soil when it has soaked in. Repeat often.

Bud Moth. - Use lime-sulphur in winter, and before leaf buds open and after blossoms fall. Repeat every ten days if necessary.

Brown Apricot Scale. - Apply kerosene or distillate emulsions just as soon as the leaves fall. Applications should be made before December 1st.

Codling Moth. - Apply lead arsenate just as soon as blossoms fall. Continue to spray at intervals of ten days or two weeks throughout the season (at least four times).

Canker Worms. - Apply lead arsenate when the worms first appear. Spray as often as needed. Tanglefoot bands on the tree are very effective in keeping the caterpillars from the trees.

Tussock Moth. - Spray in full bloom with zinc arsenite, six pounds to 200 gallons, and follow in ten days with neutral lead arsenate, fifteen pounds to 200 gallons.

Greedy Scale. - Apply lime-sulphur when trees are dormant. This scale seldom needs treatment.

Oyster Shell Scale. - Apply lime-sulphur when trees are dormant.

Pear Slug. - Dust on Paris green or other arsenicals, hellebore or Pyrethrum.

San Jose Scale. - Apply lime-sulphur when trees are dormant. Repeat in spring.

Thrips. - Spray with distillate emulsion and tobacco when the insect appears in the spring abundantly.

Black Spot Canker. - Apply Bordeaux mixture, the first and fifteenth of November.

Bitter Rot. - Apply weaker Bordeaux at first appearance of rot. Repeat every two weeks if needed.

Moss or Lichens. - Apply crude oil emulsion and lye when trees are dormant.

Pear Blight. - No spray effective. The only treatment consists in cutting off blight as fast as it appears. Cut below affected parts so that good live wood is secured. Sterilize implements after each cut by dipping them in corrosive sublimate.

Apple Mildew. - Cut off infested tips both winter and summer, also prune back all twigs somewhat as apricots are pruned. Spray with milled sulphur in spring.

Sappy Bark. - Cut away diseased parts when trees are dormant.

Scab. - Apply strong Bordeaux before buds start. Spray again with weaker Bordeaux as soon as the blossoms fall. Repeat several times at intervals of three or four weeks. (This should be done especially if the weather is damp.)

Citrus Fruits.

All scale insects and mealy bugs on citrus trees, commercially grown, are fought by fumigation with hydrocyanic gas, which see on a previous page.

Fuller's Rose Beetle (Aramigus fulleri). - This insect cannot fly and can be kept from the trees by means of tanglefoot bands.

Orange Aphis. - Spray with kerosene emulsion or tobacco extract as soon as found.

Red Spider (Tetranychus mytilaspidis. - Apply milled sulphur or dilute commercial lime-sulphur when foliage is damp. Repeat until pests disappear. A new practice which has given excellent results is obtained by adding flour to the spray as follows: four pounds flour to 100 gallons water. Make a paste of the flour, using the proportion of one pound flour to one gallon cold water, strain and add in proportion required to each tank of spray material. The advantage in using flour is that it prevents the spotting so often noted in use of lime-sulphur spray, which injures the fruit, and spreads in a thin film over the tree.

One pound of dextrine to 100 gallons of water may be used in place of the flour.

White Cottony Cushion Scale. - This pest is handled perfectly by its natural enemy, Novius cardinalis, commonly called the "Vedalia," which may be had from the State Insectary, Sacramento. Release colony at any time of year scale appears.

White Fly. - Defoliate trees when the larvae appear and scrub with soap washes. Better to fumigate with hydrocyanic gas.

Thrips. - Spray with tobacco extract in spring.

Army Worms. - Apply poison baits under trees; also if they have not already secured access to orchard, surround trees with deep furrow, vertical side toward trees. If cover crops are growing, remove such growths as project up into branches of the trees. Paint tanglefoot bands around tree trunk.

Brown Rot. - Sow cover crop in orchard. Plow under in spring and cultivate well under the trees. In washer use bluestone, or permanganate of potash. Eliminate infected fruit and disinfect boxes and picking sacks.

Dieback (Bacterial). - Improve physical conditions of trees by deeper and more thorough tilling of soil. If excessive applications of nitrogenous fertilizers have been made, discontinue until tree has resumed normal conditions.

Mottle Leaf (Physical). - Improve physical condition of tree by deep culture. Make applications of lime and manure to soil. Examine soil as to hardpan, and if it exists, break up if possible.

Smut. - A fungous growth caused by honey dew exuded by scale insects, plant lice and white fly. Remove pest and smut will disappear.

Wither Tip. - Apply Bordeaux as soon as it appears and repeat as often as necessary.


Black Scale. - Best treatment, fumigation, October-January. If sprayed use resin wash or distillate emulsion. Annual spraying not effective. When young insects appear in large numbers on leaves and stems apply spray. Two or three sprayings may be necessary in some years; in others none.

Twig Borer. - Cut off twigs and prune.

Dry Rot of Fruit. - Keep trees free from other pests, well pruned out so as to admit light and air.

Olive Knot. - A bacterial disease in the form of a woody tumor. Attacks most vigorous trees. Distributed principally by pruning tools. After pruning dip tools in corrosive sublimate. Cut off all tumors, removing the entire twig when possible, and burn.

Peacock Leaf Spot. - Fungus on leaves and fruit. Spray with Bordeaux.

Peach, Nectarine, and Apricot.

Aphis, Black Peach. - For those above ground use kerosene emulsion or tobacco wash. Destroy the underground forms by pouring carbon bi-sulphide into holes in the ground (made by a crowbar) six inches to six feet away from the tree and about two feet apart. Pour 21 around base of tree often.

Apricot Scale. - Apply distillate emulsion or tobacco washes just as soon as the leaves fall. All applications should be made before the first of December.

Black Scale. - Same as Apricot Scale.

Borer, Peach Tree. - Dig out and kill, or destroy by inserting a flexible wire into their burrows. A strip of asphaltum six inches wide on butt of tree is also used.

Bud Moth. - Use lime-sulphur during winter months when tree is dormant. Use lead arsenate just before leaf-buds open and just after blossoms fall. Repeat every ten days if necessary.

San Jose Scale. - Spray with lime-sulphur when trees are dormant.

Twig Borer. - Spray with lime-sulphur just when buds are swelling.

Blight, Peach. - Spray last of November or before December 15th with Bordeaux or dilute lime-sulphur.

Curl Leaf. - Spray thoroughly with Bordeaux. Later sprayings should be made with weaker Bordeaux.

Shot-hole Fungus. - Spray with Bordeaux about ten days before buds open and with weaker Bordeaux when fruit is about one-fourth grown.

Cherries, Prunes, Plums.

Cherry Slug. - Feed upon the upper surfaces of the leaves, exposing the veins. Spray with lead arsenate or dust dry arsenate liberally upon the trees as soon as slugs appear.

Prune Aphis. - Spray in the fall with lime-sulphur and as soon as the lice appear with kerosene emulsion or tobacco wash.

Peach Root Borer. - See same under Peach.

Canker Worm. - See same under Apple.

Brown Day Moth. - Attacks particularly the prunes and cherries. Spray with lead arsenate as soon as larvae appear.

Red Hump (Schizura concinna). - Spray early with lead arsenate. Burn cocoons.

Brown Rot or Fruit Mold. - Produces a rot on the fruit. Spray with Bordeaux early in the spring, and with weaker Bordeaux as soon as the buds begin to open.

Leaf Curl or Witches Broom. - Cut out and burn infested parts. Spray with Bordeaux early, and with weaker Bordeaux as soon as the buds begin to swell.

Leaf Spot or Shot Hole. - Produces a shot-hole effect upon the leaves. Spray in early spring with Bordeaux, when the buds begin to open with weaker Bordeaux, and when the fruit is one-fourth grown with weak Bordeaux.

Powdery Mildew. - Appears on the leaves late in the season. Spray as soon as found with Bordeaux and repeat if necessary.

Crown Gall. - If on young trees recently set from nursery, remove and burn. If bearing trees, chisel away until only the healthy wood remains. Paint with Bordeaux paste. Watch for a reappearance and treat as before.

Gummosis. - Dig out the gum pockets and wash out with Bordeaux paste.


Aphis. - In winter spray with lime-sulphur. For summer spraying use emulsions or tobacco washes.

Walnut Scale. - Spray with lime-sulphur or crude oil, when the trees are dormant.

Red Spider of Almonds. - Spray with lime-sulphur, using very weak solution, say about 1-33, or sulphur thoroughly.

Crown Gall. - If young trees, dig up and burn; if older, treat with Bordeaux paste, chiseling down to healthy wood.

Dieback. - A physical disturbance caused by unnatural soil conditions.

Walnut Blight. - Sprays ineffective. The only treatment is prevention by using resistents.


Grape Phylloxera. - Attack roots and foliage of the vines. Plant resistent stock. Be sure of your nursery stock.

Vine Hopper. - Infests foliage of the vines. Use hopper-doser in spring before adult females deposit their eggs. Spray as soon as the young begin to appear with distillate emulsion.

Grasshoppers. - Use poison baits.

California Root Worm. - A black beetle whose larvae attack the leaves, stems, petioles, roots and fruit of the vines. Cultivate deeply around the base of the vines. Spray with lead arsenate as soon as beetles appear.

Flea Beetle. - It infests the foliage and may be handled by spraying liberally with lead arsenate.

Hawk Moth. - The large green larvae of this moth feed upon the foliage. Hand pick, or if too numerous spray with lead arsenate.

Grape Leaf Folder. - The larvae roll themselves up in the leaves, which they eat. Spray with lead arsenate.

Erinose. - This so-called disease is produced by a small mite, which is characterized by forming swellings upon the upper surfaces of the leaves. Dust plants liberally with sulphur when they are wet with dew.

Nematode Root Gall. - A minute worm attacking the small roots. Destroy all infested vines. Sterilize soils with carbon bisulphide. Plant only hardy varieties where this exists.

Powdery Mildew. - Grows upon the canes, leaves and fruit. Dust often with sulphur as soon as the disease appears. Spray early with Bordeaux.

Downy Mildew. - Attacks all green portions of the plant-leaves, young shoots and berries. Spray with weak Bordeaux as soon as first appearance is made.

Blackberries, Raspberries, Loganberries, Strawberries.

Rose Scale. - A white scale thickly infesting the canes just above the surface of the ground. Spray with lime-sulphur or kerosene emulsion.

San Jose Scale. - A small scale badly infesting the canes, particularly of the raspberry. Spray with lime-sulphur.

Strawberry Plant Louse (Myzus fragariafoliae). - A light yellow louse attacking the buds, blossoms and young fruit. Spray with kerosene emulsion or tobacco washes.

Orange Rust. - Forms orange-red colored masses on the leaves, which finally kill the plant. Dig out and burn all diseased plants as soon as rust first appears.

Leaf Spot of Blackberry and Raspberry. - Produces small pale spots on the leaves. Spray with weaker Bordeaux when leaves are half grown and repeat every two weeks if necessary.

Leaf Spot of Strawberry. - This disease first appears as small discolored spots upon the leaves, which destroy the tissues of the plant. Spray before the flowers open with weaker Bordeaux. If the disease appears late, mow off and burn the leaves. Spray the newly appearing leaves with weaker Bordeaux.

Powdery Mildew of the Strawberry. - Produces a whitish powdery covering on the foliage which soon kills the plant. Dust with sulphur when the plants are wet.

Crown Gall. - Affects, especially, the blackberry. Dig vines as soon as this trouble appears; there is no cure. Secure new, clean stock and plant on fresh ground.

Currants and Gooseberries.

San Jose Scale. - A small scale infesting the stalks. Spray when dormant with lime-sulphur.

Currant Stem Borers. - Small white larvae which bore into the stalks of the plants. As a preventive, wash plants in the spring with soap solution.

Imported Currant Worm. - Attacks the leaves in the spring. Dust plants with Paris green or hellebore when they are wet, or spray with same.

Leaf Hopper. - Usually appears in great numbers on the undersides of the leaves. Spray with distillate and potash as soon as the first ones are noticed.

Currant Leaf Louse. - Usually works upon the ends of the tender shoots and stunts their growth. Spray with distillate emulsion.

Leaf Spot. - Produces large pale spots with brown borders upon the leaves. Spray with Bordeaux as soon as first spots appear and repeat as often as is necessary to keep down the disease. Spray with weaker Bordeaux twice after fruit has been removed.

Anthracnose of Currant. - Produces small brown spots upon the leaves, petioles, young canes, fruit stalks, and fruits. Spray with Bordeaux before leaves appear and with weaker Bordeaux while leaves are unfolding and repeat every three weeks until fruit ripens.

Gooseberry Mildew. - Produces a mildew upon the stems, leaves, and particularly upon the berries, causing them to spoil. Spray with weaker Bordeaux just as the buds are breaking open and repeat every twelve days until about July 1st. Spray plants in winter with lime-sulphur.

Peas, Beans, Vetch, Clover, Alfalfa.

Wireworms. - Affect beans and many other garden plants. Rotation of crops to starve out the infestations is perhaps the best treatment. Where this cannot be done, use of the carbon bisuiphide in sandy ground is advised. Fertilize with nitrate of soda or kainit.

Bean Aphis. - Works on the leaves, young shoots and tender pods, causing much damage. It is usually cared for by an internal parasite and by a predacious ladybird, but if it becomes too destructive spray with kerosene or tobacco washes.

Green Pea Aphis. - Also attacks vetch, geraniums, malva and many other plants. Spray with kerosene or tobacco washes.

Cut Worms. - Do great damage to all crops at certain seasons. Plow around field so as to have straight side of furrow next to crop. Use poison baits.

Grasshoppers. - Are very difficult to handle. Poisoned baits have given good results. Fall plowing of breeding grounds essential.

Weevils. - Fumigate seed with carbon bisulphide and be sure that no infested seed is planted. Test by placing in water; infected seeds will float.

Bean Anthracnose. - Produces brown sunken areas upon the pods. It also attacks the young plants. Treat seeds with formalin before planting. Spray with Bordeaux as soon as young seedlings are well under way. Repeat if necessary. Practice clean cultural methods.

Bean Blight. - Attacks pods and produces wrinkled and distorted seed. Treat seed with formalin before planting.

Rust. - Produces rust colored spots on foliage. Spray with weaker Bordeaux. Burn all infested plants.

Downy Mildew. - Turns foliage dark and causes it to wilt and die. Select clean seed. Spray with Bordeaux.

Pea Mildew. - Appears early and late, covering plant with a white felt-like powder. Spray with weak Bordeaux or dust with sulphur.

Onions, Leeks, Garlics, Etc.

Onion Thrips. - Attack the leaves and flowers, causing considerable damage in some localities. Spray with kerosene emulsion as an insecticide and with Bordeaux as a repellent.

Downy Mildew. - Produces a white mould on the leaves, causing them to wilt and die. Spray with Bordeaux.

Onion Smut. - First appears in the form of dark spots upon the leaves and later as longitudinal rifts upon the bulbs. The following drilled into the soil at the rate of 150 pounds per acre has given good results: lime 50 pounds mixed with sulphur 100 pounds. Also treat seed with formalin as they are being drilled into the soil.

Cabbage, Cauliflower, Kale, Turnip, Radish, Mustard.

Harlequin Cabbage Bug. - Attacks all cruciferous plants, cultivated and uncultivated, as well as many other hosts. It is no little difficulty to keep these insects from taking a crop, but by observing the following they may be held in check: Keep weeds from the fields at all times; plant late trap crops of kale or cabbage and burn them when they become infested, or kill the bugs with pure kerosene. Hand pick adult insects as soon as they first begin to appear. Spray with kerosene emulsion.

Cabbage Aphis. - Attacks a wide range of cruciferous plants, cultivated and uncultivated. In time, it is subdued by parasitic and predacious enemies, but often not until it has done great damage. It can be controlled by spraying with emulsions or tobacco washes.

Cabbage Worms. - These green worms do great damage by destroying, for market, great quantities of cabbage and cauliflower. As a repellent apply white hellebore; as an insecticide apply resin wash.

Club Root. - A disease producing peculiar enlargement of the roots, giving the plants an unhealthy appearance and finally causing their death. The disease may be carried over in the soil, so the following has been recommended as a means of control: Lime the soil at a rate of 100 bushels per acre, every few years. Rotate crops. Employ clean culture methods.

Black Rot. - A bacterial disease first producing a burnt margin on the leaves and finally causing them to drop. The disease is readily carried from year to year in the seed. Before planting treat the seed with corrosive sublimate or formalin. Eliminate infected plants as soon as they appear in the beds. Rotate crops.

Tomato, Potato, Egg-Plant, Tobacco, Etc.

Tomato Worms. - These large green caterpillars feed upon the foliage and are easily recognized. Due to their large size, it is very effective to hand pick the infested area. If very numerous spray with arsenate of lead.

Flea Beetle. - A very small beetle which works on the leaflets. As a repellent spray with weak Bordeaux; for an insecticide, arsenate of lead.

Twelve Spotted Cucumber Beetle. - A small green beetle with twelve black spots on the elytra. The larvae work on a great variety of plants. Spray with arsenate of lead.

Winter Blight or Downy Mildew. - Attacks nearly all of the plants of this family, killing the leaves and injuring the tubers. Plant clean seed. Disinfect doubtful seed with formalin. Spray plants with Bordeaux as soon as symptoms first appear.

Root and Stem Rot. - Causes a "damping-off" of seedlings. Also attacks the tubers of potatoes, the subterranean parts of the tomatoes, and the fruits touching the soil. Apply lime to aerate the soil. Rotate crops.

Dry Rot of Potatoes, Wilt of Tomatoes, Wilt of Egg-plant. - All of these diseases produce a wilt upon the host plants, affect the roots, and may even cause a "damping-off" of seedlings. Treat seed with formalin before planting. Keep weeds out of fields in winter. Rotate crops, so as to have clean soil each year.

Early Blight. - A typical leaf-blight causing brown spots to appear on the foliage. Affects potatoes, tomatoes and daturus. Spray with Bordeaux when the plants are six inches high and repeat with three applications two weeks apart. Treat seed with formalin before planting. Rotate crops.

Potato Scab. - Produces large rough blotches on the tubers. This disease cannot be dealt with while the plants are growing. Great care must be exercised in the matter of seed selection. Treat all seed of doubtful origin with corrosive sublimate. Rotate crops so as to keep the soil fresh.

Squash, Pumpkins, Cucumbers, Melons, Etc.

Melon Aphis. - Attacks all parts of the vines and is usually accompanied by a black smut, which grows upon the honey-dew secreted by the louse. Spray with kerosene emulsion or tobacco washes.

Green Lady Birds, Striped and 12-Spotted. - The larvae and adults of these beetles destroy flowers and foliage of the plants and gnaw the rinds of the fruit. Methods of control are as follows:

Repellants. - Dust with tobacco dust or with naphthalene. Soak lumps of gypsum in a mixture of kerosene and turpentine and place them under infested vines. Insecticides - Dust with time and then spray or dust with Paris green or arsenate of lead.

Squash Bug. - Hand pick early in the season; also pick off eggs and destroy. Eggs are deposited in clusters on the leaves when the vines are very young. Trap bugs by laying boards loosely on the ground under which they crawl for protection. If very troublesome, a repellent of gypsum saturated with kerosene scattered about the grounds is effective. As soon as crop is harvested, gather and burn vines. Do not allow weeds to grow on the ground during winter months.

Downy Mildew. - Disease first appears in the center of the vine and spreads outwardly. Spray with Bordeaux to which is added one gallon of sulphurous acid to every 100 gallons of spraying material. Repeat every ten days.

Leaf Blight. - Produces spots on the leaves which spread very rapidly. This disease hastens ripening, injures production and destroys the quality of the fruit. It particularly affects cantaloupes. Destroy affected plants as soon as they first appear. Spray often with weaker Bordeaux. Rotate crops.

Anthracnose. - Forms circular dead spots on the leaves and long shrunken areas on the stems. The fruits of the watermelon are often badly spotted by this disease. Spray with weaker Bordeaux as soon as fungus appears.

Common Wilt. - Produces a sudden wilt of the vines by stopping up the water carrying vessels of the stems. Destroy infected plants as soon as infection appears.

Fusarium Wilt. - Can be handled only by crop rotation.

Powdery Mildew of the Cucumber. - Attacks other members of this group also. Forms a white powdery coating on the leaves and stems and soon kills the plants. Spray as soon as it first appears with weak Bordeaux.

Celery, Carrots, Parsnips.

Celery Leaf-tyer. - Destroys foliage, and its presence may be told by the many leaves which are curled and fastened together by this insect. It is particularly bad in greenhouses. Spray with Paris green or lead arsenate not later than three weeks before marketing crops, because of the danger of poisoning. Hand pick.

Celery Blight, Early Blight. - Produces spots upon the leaves, causing them to turn yellow, to wilt, and finally kills them. This disease also affects parsnips, and usually appears early in the season. Spray early and repeatedly with weak Bordeaux.

Late Blight. - Produces rusty brown spots upon the leaflets which may rapidly spread to cover the entire foliage. Spray with weak Bordeaux throughout the season.


Asparagus Beetle. - Dust air slacked lime upon the plants when they are wet with dew. Apply lead arsenate dry. As a repellent spray with hellebore in water.

Asparagus Rust. - Attacks the bushy tops, producing black and red rust, the latter being the destructive stage. Keep the plants cut back until July 1st. Apply 150 to 200 pounds of sulphur, dry, per acre, three weeks after cutting tops and before rust appears. Make the applications in the morning when the plants are wet with dew, or first spray with weak Bordeaux.

Corn, Sorghum.

Corn Worm. - Is hard to deal with because it works on the ear in the husk. It is best handled by the rotation of crops, late plowing followed by harrowing to destroy the pupae in the soil, and by planting crop as early as possible to assure rapid growth. (See page 31.)

Corn Root Aphis. - Attacks the roots, causing a dwarfing of plants in patches over the fields. Crop rotation is the most important method of control. Stir old corn ground thoroughly before planting it again to corn.

Smut. - Causes enormous enlargements of the kernels, producing large sacs of smut. Cut off and burn the first infestations. Treat seed with formalin before planting. Rotate crops.

Wilt of Sweet Corn. - Plants die by wilting due to the shutting off of the water supply. Select resistant stock. Treat seed with formalin before planting. Rotate crops.

Combined Insecticides and Fungicides.

It is found desirable at times to combat both the insect pests and the fungi at one application of the spray and for this a combination of the insecticide and fungicide is used. This results in a saving in the cost of labor and time spent in spraying.

Carbolic Acid Emulsion.

Crude carbolic acid 5 gallons
Whale oil soap 40 pounds
Water (hot) 40 gallons

The forty gallons of water are first poured into the cooking kettle and allowed to boil. While the water is getting hot the whale oil soap is cut into fine pieces, so as to make it dissolve easily, and added to the water. When the soap is all dissolved in the hot water the carbolic acid is added, and all is allowed to boil for a short time to insure thorough mixing. The whole operation requires less than one hour. This makes about 43 gallons of rich stock solution. For spraying the stock solution is diluted one to twenty of water, thus making approximately 860 gallons of spraying material. The stock solution will keep indefinitely, but is preferable fresh. When diluted with water it makes a perfect emulsion and can be applied with any spray pump, since an agitator is not needed. When the stock solution is allowed to stand for some time it is best to stir it up before diluting it for spraying.

The resulting spray is very easily handled, it needs no agitation, no straining, is easily and simply made, does not rot the hose or rust iron pipes, and is perfectly harmless to the eyes and hands of the sprayers.

Bordeaux-Arsenate of Lead.

Acid lead arsenate 3 pounds

Bordeaux mixture 50 gallons
or Arsenate of soda 10 ounces

Acetate of lead 24 ounces

Bordeaux mixture 50 gallons

Prepare the commercial arsenate of lead by working into a smooth paste and add it to the diluted milk of lime. Prepare the home-made arsenate of lead as follows: Take the arsenate of soda and dissolve this in a gallon of water (preferably hot) and in another gallon of water dissolve the acetate of lead. When completely dissolved pour the two simultaneously into the mixing tub containing the rest of the fifty gallons of water; stir well and the spray is ready. The use of wooden vessels is advised in handling these solutions.

Where a stronger poison is desired the arsenate of lead can be increased to three or four pounds. A more uniform distribution of the arsenate of lead is secured throughout the spray when it is added to the milk of lime instead of placing it in the spray tank.

Bordeaux-Paris Green.

Paris green 4 ounces
Bordeaux mixture 50 gallons

Mix the Paris green into a thin paste and add to the milk of lime and proceed to mix the Bordeaux according to the directions given in Formula No. 1.

First mix the arsenate of lead with two or three gallons of water.

Lime-Sulphur-Arsenate of Lead.

(a) Lead arsenate (neutral by ammonia test) 3 pounds

Dilute lime-sulphur 50 gallons
(b) Arsenate of lead 2 pounds

Self-boiled lime and sulphur 50 gallons

Have the arsenate of lead in the form of a smooth paste and add to the lime and sulphur solution, at the same time stirring the spray thoroughly. If a power sprayer is used it is advisable to keep the agitator working.

Ways to Fight Destructive Animals.

Protecting Foliage.

What will keep deer from eating the leaves and tender twigs of young fruit trees? Last year I set out 1,000 young apple and pear trees and the deer ate the foliage off three times during the season. This last spring I set out 1,500 more and the deer went at them about two weeks ago and last week they very nearly cleaned them all up. Do you know of anything that we can spray the foliage to keep them away?

A spray which will keep chickens and rabbits from eating leaves will probably make them too bitter for deer. W. C. MacFarlane of Hanford advises as follows: "I asked for a remedy to prevent poultry eating the leaves and bark off the peach trees, and was advised to use a quassia chip solution. As I had handled quassia solution on a commercial scale, I felt sure that would answer the purpose, and it did. The fowls would seldom take more than the second bite. I used a spray pump and sprayed it on the lower part of tree and trunk. I made the solution as follows: Quassia chips, two pounds to one gallon of lukewarm water; let this soak forty-eight hours; strain off the liquid and add one-half gallon of fresh water to the chips and boil down to one quart; draw this off and mix with the first water. You have then a solution poisonous to flies and insects, but, in small doses, not harmful to persons."

Another very bitter stuff is made in this way: One pound of commercial aloes to four gallons of water; mix and spray. Whale oil soap, one pound to four gallons of water would probably disgust any deer.

Remedies for Rats.

Please give some tested recipes for rat killing.

Rags, saturated with carbon bisulphide, were put down the holes and the rats died, and after two years' time had not come back. If you can get the gases of carbon bisulphide near the rats they will surely die.

I used a few dollars' worth of all kinds of poisons, but the rats didn't eat it at all. I had a white Spitz dog, who one day was scratching around the woodpile, and I helped him. We got five young and one old rat. After that I dug around everywhere. I found a hole and he got, in three days, over eighty rats. One afternoon I took all the hay out from the barn, and he got over fifty rats in about two hours. - Joseph Schatzeder, Santa Rosa.

I took a few small eggs, punched a little hole in the side of each, and put in a small quantity of strychnine, two or three crystals is quite enough. For about a fortnight they took the eggs every night, then they began to leave them, and in three weeks there was not a rat on the place, and ever since they have given this place a wide berth. I tried all kinds of traps and poisons; traps they avoided, and poisoned bait they wouldn't touch, but eggs, no matter how much you handle them, they never refuse. Wherever this remedy has been tried it has proved effectual. The eggs must be placed in their runways out of the reach of dogs, as they also are fond of eggs. - Sam'l Haigh, San Jose.

Feed rats dry meal for about one week, always feeding them in the same place, and having plenty of water near by, and then add about one-quarter as much plaster of Paris, feeding for the same time and at the same places with plenty of water near, and no rats can live. The plaster and meal must be well mixed and the meal should be very fine. The plaster "sets" in the alimentary canal and the rat soon dies. - W. H. Konkel, Rierman.

We placed hot savory table scraps where rats would get them, increasing the amount if it was all eaten, for four nights, to get all of them interested. On the fifth night, plaster of Paris was added to a big moist meal and the rats froze in their tracks not more than three or four feet away. The rising generation were disposed of a little later. - Arthur Walton, Yucaipa.

Buy a cheap sponge, cut it into small pieces, and fry it in grease. The rat being of a hungry and, greedy disposition will swallow it whole, as he can't chew it, then the sponge will expand and swell up and the result will be a death from constipation. I have tried it with good results. - A. Rensch.

Poison some fresh meat with arsenic and place the poisoned meat near a dish of water. I have used this system with good success. - J. E. Thorp, Stockton.

A sure way to kill rats is to get some Victor rat traps and bait them with dried French prunes. The trap costs 15 cents. I have tried different bait, but the dried prune is the only sure way. - C. A. Iverson, Paso Robles.

Walling-Out Gophers.

I am growing alfalfa with a sprinkling system with network of pipes as the land is gravelly and porous and it is impossible to flood to drown the pests. I have had a fairly good stand, but in spite of cats and traps the alfalfa is riddled with gopher holes, which are destroying the roots. I have thought of putting a rock and cement wall around the alfalfa field, going four to six feet deep and two feet above ground. Can gophers go deeper than this? There is plenty of rock on the place and we can do the work ourselves. Has this ever been tried?

You will surely get no gophers to speak of from the outside if you build such a wall, but it will be fiercely expensive in digging and masonry even if you do all the work yourself. We believe that gophers do not go as deep as four or six feet. We cannot find record of any extreme depth found by those who have studied burrows by abundant excavation, but they are said by all investigators to be shallow and only a little deeper for housing purposes. Few if any would dig under a wall half the depth you mention. They do surface running at night, during the mating season, but probably a one-foot barrier would stop that. If you build one foot above ground and two feet below you will practically have them shut out.

You can also protect your place very largely by digging a ditch with vertical sides two feet deep all around it and keeping that ditch open. Dig the width of a coal oil can and bury cans even with the bottom of the ditch at intervals of twenty-five feet. Digging gophers will take headers into the ditch, run along the bottom of it until they plump into the oil cans, from which they cannot climb out. Such pitfalls have been considerably used and captures of gophers by the hundreds have been reported. Cats have also been seen to help themselves from the cans - so you can have a combined ditch, can and cat system which will work automatically. If in addition to this protection you get the knack of using traps to catch those now inside the patch, you may get a little rest and more alfalfa.

Poisoning Gophers.

Are there any newer and better ways with gophers?

Take a narrow pine board which will split easily and straight and saw off blocks sufficient to make, say, from 100 to 1,000 "toothpicks" about three and a half inches long. I sharpen both ends of each "pick." Next, I put a raisin (into which I have pricked a little strychnine) on one end of pick and place in a tight fruit-jar labeled "Poison." These I keep in stock. I carry in my vest pocket, in a suitable receptacle, about twenty of these impaled raisins. When I discover an open hole I simply plant the sharpened end of the pick into the side or roof of the hole, and the gopher cannot help but see it, and nineteen out of twenty will eat it and die. I put one into each opening. - J. H. Hubbard.

The chief requisite for poisoning is to get the baits into the main tunnel. If left in the lateral, where the gopher is working, the baits are frequently pushed out with the soil, to be wasted, or possibly become a source of danger to birds or other animals. Baits made of pieces of potato, carrots, beets, raisins, prunes, shelled corn, and green alfalfa have all been used with success. Baits of the first materials should not be larger than a hulled walnut. The first five are prepared by cutting a slit in the bait and inserting some strychnine sulphate, about equal in bulk to half a grain of wheat. To prepare the grain or alfalfa, soak in a solution prepared as follows:

Dissolve one ounce of strychnine sulphate in a quart of boiling water, add a quart of thick sugar syrup and stir thoroughly. This formula is sufficient to poison thirty-five pounds of grain, or thirty pounds of green alfalfa. In treating alfalfa, add a little more water. If a little borax is added to this syrup it will keep for several months.

To locate the main tunnels, force a pointed stick into the ground at a point midway between the last fresh openings. The poison may be dropped through the opening made by the prod. This saves the labor of digging for the burrow.

The ordinary gopher traps are usually effective when set in the freshest openings. After setting the traps, the opening should be closed or left with only a little light entering.

On land that can be readily flooded, the gophers will be driven to the surface where a small dog will make short work of them. - W. B. Parker.

Killing Squirrels.

Ground squirrels live in burrows which are, in the majority of instances, not more than eighteen inches to two feet below the surface of the ground, and run in general more or less parallel to the surface. In some cases burrows may go deeper.

Female ground squirrels have usually not more than one litter of young in a year; the number of young in a litter varies from four or five to a dozen or more - the average is about eight. The breeding season begins in November and continues for several months, the young being born between March first and June first; this period varies somewhat in different localities.

When the young are six weeks to two or three months old they either leave the burrow in which they were born or are driven out by their parents, and open burrows for themselves in some other locality. The nearness of the new burrows to the place of birth will depend upon how numerous other squirrels are, or upon the location of a desirable food supply.

Poison for Squirrels. - Barley is the best kind of grain to use. Wheat, oats and other grains have been used, but extensive observation has proved that more uniform and better results have been obtained by the use of barley than with any other grain. Further, it is not so likely that it will be eaten by chickens, quail, pigeons, doves, turkeys and other birds or fowls, nor by sheep or other animals, as will other kinds of grain. The best poison to use is strychnine, the barley being coated with it in accordance with the "Government formula," as follows.

Whole barley (recleaned) 18 lbs.
Strychnine sulphate 1 oz.
Soda (bicarbonate) 1 oz.
Saccharine 1 oz.
Thin starch paste 1 Pt.
Corn syrup (Karo or equal) 2 ozs.

The best results are obtained by scattering the poisoned grain on the ground early in the morning, back of the hole. Not upon excavated dirt that the squirrel has thrown out. It should not be spread before a rain or when the ground is wet or when there is a heavy dew, as the poison will be washed off and no results obtained. It should be widely scattered so that the squirrel will be compelled to pick it up a grain at a time and place it in the cheek pouch.

Fumigating Squirrels and Gophers. - When the soil is moist excellent work can be done with the fumes of carbon bisulphide or "kilmol." A ball of waste jute or gunny, cotton, horse manure, oak ball, or other absorbent material is saturated with kilmol or carbon bisulphide and placed in the mouth of the squirrel burrow; the hole may then be closed with dirt and the gas allowed to diffuse throughout the burrow. This will be sufficient in many instances; as a general rule, however, it is better to ignite the ball with a match or torch. A sharp explosion usually occurs immediately, which forces the burning gas deeply into the burrow. The burning of the bisulphide produces sulphur dioxide and carbon dioxide, both of which are poisonous if breathed for a sufficient length of time in an inclosed space. Kilmol, when ignited, also produces sulphur dioxide and carbon dioxide and contains other powerful irritants in addition which set up a violent inflammation in the lungs of the squirrel, so that the effects are severe and lasting.

The waste ball method is applicable only when the ground contains sufficient moisture to prevent the formation of cracks and crevices through which the poisonous gases could escape. There is also danger of fire where the vegetation is dry enough to burn.

The Squirrel Destructor. - The squirrel destructor is an apparatus for forcing poisonous gases into the squirrel burrow. It is constructed principally of galvanized iron and is simply a double action air pump which forces air through a chamber into which one ounce of kilmol or refined carbon bisulphide has been measured. Forty strokes of the pump forces thirteen cubic feet of air through the liquid used, thus forming a vapor which displaces the air in the burrow and remains for several hours. The squirrel promptly becomes unconscious and dies in from twenty to thirty minutes to forty or forty-five minutes, depending upon the liquid used and upon the tightness of the ground surrounding the burrow.

The squirrel destructor is usually effective against gophers. In some cases, however, the gopher will plug his burrow and thus escape the poisonous gas. It is desirable to put in a double charge and pump twice the ordinary number of strokes.

Sulphur-Balls for Gophers. - Fred Lewis of Santa Clara County suffocates gophers with sulphur balls made by tieing a couple of tablespoonfuls of dry sulphur in a dry cloth. He digs beside any fresh mounds, lights a sulphur ball with a match, being sure it is burning; pushes it into the hole, blows across it to force smoke out of any other holes to that burrow which may be open, so that he may cover them up; then covers all openings; smoothes down the dirt so if the gophers live through the smudging he will know it by fresh piles, and proceeds to the next. Sometimes the smoke comes out of five or six holes at once, but after closing these he has never known a gopher to dig out.

Baits and Poisons for Coyotes.

I wish to know o good recipe for coyote bait or scent.

One of the most common scents is made by cutting up a fish which is rich in oils, such as trout or eel, into small pieces and putting these in a corked bottle. When this is placed out in the sun it gives off a rancid oil with a very odorous smell which wild animals like.

Another good scent is made by putting common angle worms in earth which is saturated with milk. In order to prevent the worms from escaping, a boxful of earth should be used. After the worms are bloated with milk put them in a corked bottle in the sun until the mass has decomposed.

Skunks are also considered to be good scent, as coyotes will follow the scent of them for miles, and when they find it, will always lie down and roll on it.

Any kind of meat is good for bait, but of all fresh meat, liver is the best. Rabbits, squirrels, and doves are also good. Kill them and insert poison while the body is warm so that it will circulate through the system. Fresh meats of any kind rarely give the same satisfaction as dried meats, for the reason that buzzards, hawks, and other birds of prey detect it, and oftentimes carry it off.

When dried bait is used, which is no doubt the best of all, it must first be sprinkled with! poison or insertions of poison made in it, then it should be hung in the sun to dry thoroughly.

This kind of bait can be carried easily and placed almost anywhere without being molested by the fowls of the air and will keep for months if placed in a dry location.

To poison a hog pasture the best method is to bore a hole one inch in diameter and three inches deep on each side of several 4 x 4 inch blocks. Take equal parts of tallow and lard, melt just enough to make it run together; add poison, and pour into the holes. Place these blocks in different parts of the field where coyotes are accustomed to prowl and you will get them. If possible, roll a dead skunk over the blocks or put them on the trail where a dead animal has been dragged. This is also a very good way where birds, hawks, and buzzards steal baits.

When all means of trapping and poisoning have failed to get a coyote which is raiding poultry, take a chicken - a white one is best, and a sick one, too, for that matter-pull a few feathers out of its back, sprinkle pulverized strychnine in the place, and stake it out by the leg. The chicken will usually live long enough to capture him. If this is too cruel, place a small chicken coop inside of a large one, equal distance from all parts, and fasten securely. Then put several chickens in the small coop-one or two crowers are the best. Take the coops and chickens to a place frequented by coyotes, place traps all around the coop, cover and leave them until you catch your thief. It may be several days, but feed the chickens and leave them there and you will get the varmint.

Strychnine is the most effective poison for coyotes and should be used sparingly as it does not require much to kill.

If they start to eat a bait and it is too bitter with poison, they will drop it from, their mouths. Enough pulverized strychnine to cover half an inch of the point of the small blade of a pocketknife is enough to put in each bait.

The best time to poison is when coyotes prowl about in packs, as they eat nearly everything they can find. The reason of this is that several discover the bait at the same time, making a rush for it, and the first one getting it eats it in haste, without suspicion, to keep the others from it.

The carcass of a young calf makes excellent fresh-meat bait. Drag it about the field on horseback before poisoning, then put the poison in the ears, mouth and chest. Unless there are quite a number, they will eat only part of it the first day, usually commencing with the flank and devouring the hind quarters. This will not kill them, so encourages them to come again, and perhaps bring others with them. You will likely get several, as they eat nearly everything of a young calf, even the head.

[1] - This information is compiled from the latest writings of E. O. Essig, instructor in entomology of the University of California.

[2] - Chiefly as stated by W. H. Volck, horticultural commissioner of Santa Cruz County.

[3] - Adapted from the writings of W. H. Volck, Horticultural Commissioner, Santa Cruz County.

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