The spraying of plants [microform] : a succinct account of the history, principles and practice of the application of liquids and powders to plants, for the purpose of destroying insects and Fungi

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Preface

In looking back over the past ten or twelve years, it is difficult to realize the rapid advance made in combating the insects and fungi which attack our cultivated plants. It is not going too far to say that the discoveries made within this period have worked almost a revolution in certain lines of agriculture. So phenomenal has been the progress in this direction that we are sometimes led to think that we have gone forward too fast, for in our intense desire to make the work thoroughly practical we have in many cases merely skimmed the surface, overlooking some of the most important fundamental questions involved. However this may be, the fact remains that America to-day stands well to the front in the discovery and application of practical methods of dealing with the numerous insect and fungous enemies of cultivated plants. The advance in this department has been so rapid that it has hardly been possible for investigators to keep track of all that has been written on the subject, nor has it, under the circumstances, been an easy matter to pause and consider what is to be the final outcome of work of this kind. This seems to be a fitting time, therefore, to take a broad survey of the subject in order that we may see where we stand. Mr. Lodeman has done this in the present volume, in which is given a clear, concise statement of the existing condition of our knowledge on

ix

X Preface.

the spraying of plants and the fundamental principles underlying this operation.

As to the future, it can only be said that the prospect for broadening the work so well begun is exceedingly promising. As yet it cannot be stated that we have a well-defined science of plant pathology, but gradually the investigations and thought in this direction are being crystallized. It is now realized that to truly understand and appreciate pathological phenomena we must be familiar with physiology, the normal life processes of plants. After all, the highest aim of the investigator in this field of research is not to deal only with efEects as he finds them, but to study causes, as it is only by this means that the true nature of many of the phenomena involved can be obtained. Following this line, we shall in the future look for a science capable of elucidating the problems which form the very basis of agricultural and horticultural pursuits.

B. T. GALLOWAY.

Washington, D.O.

Contents

Pabt I.

THE HISTORY AND PRINCIPLES OF SPRAYING.

CHAPTER I. Early Hibtobt of Liquid Applications

First Applications to Plants — Present Distribution of Insect and Fungous Parasites — Oceans as Barriers — Protective Applications the Most Effective Measures — Spraying Defined — Early Recommendations — Vinegar — Rue — Urine — Dung — Destruction of Plant Lice — Tobacco, Water, Powder — Soap — Soot — Sage — Hyssop — Wormwood — Lime — Petroleum

— Turpentine — Tansy — Leek — Hellebore — Oils — Sulphur — Paints — Washes — Forsyth's Composition — Ashes — Sand — Plaster — Burnt Bones — Decoction of Walnut Leaves

— Train-oil — Whale-oil — Flax Rubbish — Sea-weed — Seashells — Sea-sand — Mortar Rubbish — Clay — Tanner's Bark — Leather Scraps — Salt — Corrosive Sublimate — Alcohol — Potato Water — Decoctions of Elder — Bitter Herbs — Pepper

— Lye — Pot and Pearl Ashes — Tar — Hot Water — Soft Soap

— Farmyard Drainage — Brimstone — Burdock Leaves — White Hellebore — Nitre — Whale-oil Soap — Nux Vomica — Scotch Snuff — Cayenne Pepper — Aconite — Pigeon Dung — Eau Orison — Quassia Chips — Copper Sulphate — Various Formulas containing these Ingredients — Applications recommended against Canker — Cantharides — Plant Lice — Mechanical Injuries — Canker-worms — Red Spider — Insects on

xi xii Contents.

Melons — Scale Insects — Apple-tree Borer — Slugs — Caterpillars — Bed-bugs — Brown Turtle Insect — White Scaly Coccus — Pine-bug — Peach Mildew — Woolly Aphis — Aphis — Thrips — Wood-lice — Insects on Fruit Trees — Currant Worm — Bose-bug — Mildew on Chrysanthemum, Grape, Gooseberry

— Curculio — Rose Mildew.

CHAPTER II. Spraying in Foreign Countries. in france

Discursive Trials of Fungicides (page 19). — Acetate of Potassium

— Sulphur — Downy Mildew of the Grape in France — Powdery Mildew of Grape — Powders — Iron Sulphate — Plaster — Fungivore — Pear Diseases — Sulphuric Acid — Copper Sulphate — Spores affected by Copper Sulphate — Treatment of Grape Anthracnose — Copper Sulphate upon Posts, Tying Materials, and Stocks — Phenic Acid Emulsion.

Origin of the Bordeaux Mixture (page 24). — An Accidental Discovery — Early Experiments in its Use — Downy Mildew first systematically treated with Bordeaux Mixture — Other Materials tested — First Published Formula for the Bordeaux Mixture — Tomatoes sprayed with Bordeaux Mixture for Rot — Recommendations for Treating Potatoes — Treatment of Beaune

— Treatment of Millardet — Spraying with Simple Solution of Copper Sulphate — Spraying with Milk of Lime — Treatments with Powders.

Origin of the Ammoniated Copper Fungicides and Various Comhinations (page 30). — The Use of Eau C61este — A Dilute Bordeaux Mixture — Bouillies Bourguignonnes.

Powders (page 32). — Podechard's — David's — Sulphosteatite — Sulfatine.

Perfection of Fungicides (page 34). — Stock Solutions for the Bordeaux Mixture — Treatment of A. Bouchard — Modified Eau Celeste — Bouillie Berrichonne — Treatments for Anthracnose of Grapes — Tests of Fungicides — Grape Black Rot in France — Bordeaux Mixture containing some Dissolved Copper — Bor-

Contents. xiii

deaux Mixture Celeste — Bordeaux Mixture and Molasses — Tests of Fungicides — Boi-deaux Mixture, Various Formulas and Combinations — Treatments for Pear Diseases. Insecticides (page 60). — Soap — Alcohol — Aloes — Oxalic Acid — Fichet's Insecticide — Petroleum — Kerosene Emulsion — Sulphide of Potassium -- Benzine — Glue — Salicylic Acid — Red Oxide of Mercury — Carbonate of Soda — Carbon Bisulphide — Pyrethrum.

IN ITALY (page 63).

Early Applications — Adoption of French Practices.

IN OTHER CONTINENTAL EUROPEAN COUNTRIES (pagC 63).

Treatments for Oidium Tuckeri — Introduction of the Grape Downy Mildew — Adoption of French Practices — Present Methods.

IN ENGLAND (pagC 64).

Slow Adoption of the French Methods — Potassium Sulphide — Introduction of Copper Sulphate — French Journals quoted — Insecticides.

IN AUSTRALASIA (pagC 67).

Experiments with Fungicides — Introduction of French and American Practices — Tasmanian Spraying Laws.

CHAPTER III. Spraying in America

in the united states.

Spraying for Leaf- eating Insects and the Codlin-moth (page 69). — Appearance of the Potato Bug — First use of Paris Green — First use of Paris Green for the Canker-worm — First use of Paris Green for the Codlin-moth — First use of London Purple — Introduction from England — Paris Green and London Purple compared.

Spraying for the Curculio (page 68) — The Arsenites and the Curculio — Discussion of the Value of Spraying for Curculio — New York Practices — Ohio Practices.

xiv Contents,

Other Arsenites (page 74). — Paris Purple — English Purple Poison — White Arsenic — White Arsenic and Lime.

Caustic and Non-poisonous Insecticides (page 77). — Alkalies — Quassia — Pyrethrum — Kerosene — Kerosene Emulsions — Cook's Hard-soap Emulsion — Cook's Soft-soap Emulsion — Hubbard-Riley Emulsion — Resin Soaps — Resin Washes and Compounds.

History of the Fungicides (page 87). — First Materials tested — Hyposulphite of Soda — Sulphide of Lime — Sulphur — Measures adopted against Grape Diseases before the Use of Copper Compounds — Publication of the French Discoveries and Recommendations.

The Warfare against the Various Fungous Diseases (page 92).

— First Formulas for the Copper Sulphate Solution, Milk of Lime, Copper Mixture of Gironde, Podechard's Powder, Kerosene Emulsions — Early Treatments of Grapes with Copper Fungicides — Tests of Fungicides — Spraying in 1887, Formulas recommended and the Plants treated — Spraying in 1888 — Spraying in 1889 — General Treatment of Fruit and Nursery Stock — Combinations of Insecticides and Fungicides — Lime and Arsenites — Spraying Greenhouse Plants — Spraying during 1890 — Improvements in Fungicides — Treatments for Potatoes

— Spraying during 1891 — Dilution of the Bordeaux Mixture — Tests of the Most Promising Fungicides — Spraying since 1891

— Control of Black Knot.

IN CANADA (page 112).

First Adoption of Methods recommended in the United States —

Spraying in Ontario — History of Spraying in Nova Scotia —

Canadian Publications.

CHAPTER IV. The Materials and Formulas used in Spraying

An Alphabetical List of the Most Important Materials used in Spraying, with Directions for their Preparation and Use.

Contervts, xv

CHAPTER V. Sfkaying Devices and Machinery

I. HISTORY OF SYRINGES AND PUMPS (page 181).

Heath Brooms — Watering-cans — Syringes — Fountain Pumps — Garden Engines — Knapsack Tanks — French Knapsack Pumps — American Knapsack Pumps — Introduction of Barrel Pumps — Types of Barrel Pumps — Introduction of Power Sprayers — Spraying with Steam — Spraying with Gas Power — Device for Mixing Kerosene and Water.

II. EVOLUTION OF NOZZLES (pagC 197).

Three Principles the Basis of all Spray Noz^es — The Groups of Nozzles — History of Each Group — Value of the Nozzles of Each Group.

III. BELLOWS AND POWDER GUNS (page 204).

Hand Bellows — Power Bellows.

IV. COMPARISON OF LIQUIDS AND POWDERS (page 206).

Advantages of Powders — Defects of Powders — Value of Liquids.

V. MERITS OF THE VARIOUS SPRAYING DEVICES (page 207).

Materials used for Making Spraying Machinery — Knapsack

Pumps — Hand Syringes — Bucket Pumps — Barrel Pumps —

Cylinders — Pistons — Handles — Air Chambers — Agitators —

Base-castings — Types of Barrel Pumps — Horizontal-acting

Pumps — Spraying Rigs and Outfits — Orchard Spraying —

Power Machines — Spray Nozzles for Different Purposes —

Character of Sprays.

CHAPTER VI. The Action of Insecticides and Fungicides

The Certainty of their Action — The Time to Spray — The Manner to Spray — Insecticide defined — Fungicide defined.

r

' ''i^ojif iKHKcn (page 227).

t I, " '/i '''''*''''^ '^^ ^''''»^^^ — liisecjticides deso^ ' ' //' M\ I "*'"'''*' '''muinent of Insect EnemiflB-TnHififQr-

/, " "*• *'"' * «»HI lloHlthfulness of Sprayed Apples and

^^ ^ »«HMm,u,.| ro|>,H.r uixm Sprayed Grapes -Effect of ,.,,^ l' '" *^**<»'.>* «*''»MuHii^ Stock in Sprayed Orchards

' " ^*' ''^ - * ^ ^ Compounds and the

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^' ' ' - -vw A.vur.t>,^>^— Keeping QuaUties

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Contents. xvii

Cherry — Chrysanthemum — Com — Cotton — Cottonwood — Cranberry — Cucmnber — Currant — Dahlia — Eggplant — Elm — Gooseberry — Grape — Greenhouse Pests — Hollyhock

— Maple — Mignonette — Mosses and Lichens — Muskmelon — Oats — Onion — Orange — Pansy — Parsley — Parsnip — Pea

— Peach — Pear — Plum — Potato — Privet — Pumpkin — Quince — Radish — Raspberry — Rose — Shade Trees, Shrubs

— Spinach — Squash — Strawberry — Sweet Potato — Sycamore

— Tobacco — Tomato — Turnip — Verbena — Violet — Watermelon — wftgelia — Wheat — Willow.

Appendix

A. Laws regarding the Spraying of Plants (page 376).

In California — In Canada — In Massachusetts — In Michigan — In Oregon — In Utah.

B. Metric System (page 382).

INDEX (page 384).

THE SPRAYING OF PLANTS.

Part I. THE HISTORY A^'B PRIJ^CIPLES OF

SPRAYIJ^G.

Chapter I. Early History Of Liquid Applications

Man's power over the organisms which injure cultivated plants was never so great as it is at the present time. One by one these enemies have been carefully studied, the history of their lives determined, and their habits observed. Only by understanding them thoroughly can proper steps be taken to check their ravages in the most economical and efficient manner ; yet it is within comparatively recent years that this first step was taken to obtain the mastery over them. Formerly, when a pest injured a plant, it was no uncommon practice to apply any remedies or materials that came to hand, regardless of their probable efficiency. It was not generally the weakest point of the organism that was assailed. In many cases it was not even the proper organism which was held responsible for the injury. Nevertheless many valuable discoveries came from these varied and desultory treatments, and some of the remedies most highly prized to-day were discovered merely by chance, not very many years ago.

Present knowledge and methods of investigation, largely founded upon this experience, enable us to arrive at conclu- B 1 sions which, from the outset, are founded upon a sound aod logical basis. It is fortunate that this is the case. The number of the enemies of cultivated plants is either now more numerous than formerly, or the attacks are much more energetic. It is undoubtedly true that the maladies of cultivated plants are much more widespread. This fact is mostly due to the greater food supply, and to the greater ease with which most of the injurious forms can pass from one part of the countiy to another, because the cultivated areas lie so close together. If si plant is grown to any considerable extent, it is easy for its enemies to spread over the entire region in which it is cultivated. Physical barriers are almost without value in checking this spreading of disease. The ocean is only a partial exception, since such close means of communication have been established between all parts of the globe that this obstacle is now of little avail. Some diseases have not yet been able to overpass it, but as it has proved of little hindrance in so many cases, it is probable that ultimately the enemies and diseases of plants will be as widespread as are the plants upon which they flourish. Weedy plants, insects, and possibly also fungi, are frequently more destructive in a new country than in their old home. They are freed from the enemies or conditions which formerly kept them in check, and in some cases they are the cause of very serious disturbance, although originally they may not have been markedly destructive.

Farmers and fruit growers cannot fence out the many forms of insects and fungi which live upon their crops and which are as anxious for a harvest as the grower is. It is a fight between the grower and the pest, and it must be admitted that the latter has generally had the best of the battle. The farmer has not been properly equipped. He has often had invisible foes to contend with, — foes which he did not understand, and whick he could not assail. It frequently occurred that an entire crop was ruined in a day or two, and the cause remained unseen and unknown; and even if it was visible, almost the only remedy upon which the grower could rely with certainty was mere force, first catching the pest and then destroying it. As this could be done with profit only in rare cases, it was little better than no remedy, and the general result was that the insect or the fungus obtained an ample supply of nourishment, and the grower took what was left. Indeed, this method is still followed by many cultivators, but it is not the safest, nor is it the most profitable one.

The best is generally the most profitable commodity, and the poorest is the least so ; and the grower of to-day has it in his power to produce the best. It rests entirely with him whether his apples shall be wormy or not, whether his trees shall retain theii* foliage or lose it from disease. There are few evils that affect his crops which he cannot control, in many cases almost absolutely. Only a few diseases remain which still refuse to submit to treatment, but the number is rapidly decreasing, and the time will come when these also will disclose some vulnerable point which will allow of their destruction.

Fpremost among the operations by means of which cultivated plants are protected from their enemies, is spraying. This consists in throwing upon plants any fluids, or semi-fluids, in the f ori^ of a fine rain or mist. It rests upon the general principle of cpvenng the plants, or the parts of plants to be protected, with a tl^in but uniform layer of some material that is poisonous, caustic, or offensive to the organism which it is desired to destroy. The word " spraying," as understood in this connection, has not been in general use more than ten or fifteen years, for the operation previous to this time was practiced only to a very limited eictent. It was then referred to as "syringing," from the fact that hand syringes were generally used as a means of making the applications. This term is still in common use among florists and gardeners, whose daily duty it is to throw water upon their plants either for the purpose of promoting growth, or in order to keep them free from foreign matter, such as insects or dust. It is essentially a term which, in this country, is used in connection with plants grown wholly or partially in a greenhouse or in some similar structure. Spraying, on the other hand, is a term now used by farmers and fruit-growers to designate a similar operation, but the plants treated are grown entirely out of doors, and pure water is rarely used. The operation of both syringing and spraying is, however, the same ; namely, the throwing of liquids, more or less finely divided, upon plants or other objects.

It is impossible to tell when plants were first syringed. It is very probable that the value of the operation was understood as soon as the cultivation of plants began to attract serious attention. The immediate causes which led to the practice were undoubtedly the same as those now existing. Foliage almost invariably looks brighter and fresher when wet, and one instinctively feels that if the appearance of a plant is improved by a certain operation, the general health of the plant is improved to an equal degree. The removal of insects or any injmious substances would have a similar effect, and all good gardeners would feel a temptation to improve their plants in this simple way.

Insects and diseases have unquestionably troubled cultivators from the time plants were first grown. Remedies would naturally be sought, and it appears that these older gardeners were controlled by the same feeling which even to-day often manifests itself in connection with the taking of medicine : the worse the drug smells or tastes, the more good it is supposed to do. Early in the seventeenth century Parkinson advised the use of vinegar to prevent canker on trees, and the recommendation was supposed to rest upon a very firm foundation.^ One old record ^ giving instructions for making liquid applications of an insecticide reads as follows : " Cantharides (Cantarides) are flies which attach themselves to the branches near the upper parts of trees, especially on the ash. They may be destroyed by pouring or throwing on the tops of the trees, by means of a small pump, water in which has been boiled some rue." Ruta graveolens is probably meant. This herb has a strong, heavy, and veiy disagreeable odor, and a sharp, bitter taste. K such qualities make a plant a good insecticide, rue should be one of our most valuable remedies. It seems very probable that the idea of selecting materials which are offensive to the senses was uppermost in the minds of those who first had occasion to use them, for most of the earlier substances recommended are of

1 John Parkinson, "Paradisns," The Ordering of the Orchard, Chap. ylii. 550. 1029 : ** The canker is a shrewd disease when it happeneth to a tree ; for it will eate the barke round, and so kill the very heart in a little space. It must be looked into in time before it hath runne too farre ; most men doe wholly cut away as much as is fretted with the canker, and then dresse it, or wet it with vinegar or cowes pisse, or cowes dung and urine, &c. untill it be destroyed, and after healed againe with your salve before appointed."

> ''La Th^orie du Jardinage," 166, 1711. dee also Deane, "The Newengland Farmer," 177-184.

this character. A great variety of materials must have been tested again and again by various persons independently of each other. Those materials which possessed real or imaginary remedial values, or which from their very nature appeared to possess them, remained in use until something that promised better could be found. Thus it came that at the close of the eighteenth century, and early in the nineteenth, the number of things recommended against various diseases was large, and some of the compounds possessed considerable insecticidal value. The following examples may here be cited :

'* In the year 1763, there appeared in the papers of Marseilles a remedy for plant-lice. The applications should be made by means of a small tin syringe having a nose pierced by about one thousand holes. The instrument is filled with water in which lime has been slaked, previously mixing with the clear liquid some bad tobacco, finely powdered ; this should be used at the rate of a handful to two liters of the liquid. The trees are syringed with the mixture, and although the foliage remains uninjured the pests are destroyed. But after four or five days the trees should be again syringed, using clear water." ^

" But many of the plant-lice may be destroyed by passing the leaves upon which they are found between two sponges wet with tobacco water. Ground tobacco powder spread upon the insects will kill them instantly. One may also use with it the water of slaked lime or of strong soap, soot, sage, hyssop, wormwood, and other bitter or strong-smelling herbs. Soot, lime, and soap have the disadvantage of staining the leaves, fruits, and the plants to which they are applied. Tobacco and wormwood leave small particles upon the portions treated. Other materials are often without value. Tansy, hellebore, rue, leek, bitter gourd, and long pepper have the disadvantages mentioned above. Petroleum, turpentine, and other oils are also recommended ; but care must be taken in their use, since they also act upon the plants, making them sick or even killing them." 2

" First wet the trees infested with lice, then rub flowers of sulphur upon the insects and it will cause them all to burst." *

Forsyth in 1791, ^ gave directions for the preparation of a compound which became generally known as "Forsyth's Composition." The ingredients were apparently standard remedies at this time, and they persisted long after his composition went out of use. It was made as follows :

" Take one bushel fresh cow dung, one-half bushel lime rubbish from old buildings, one-half bushel wood ashes, one-sixteenth bushel pit or river sand. The last three are to be sifted fine before they are mixed. Then work them well together with a spade, and afterward with a wooden beater until the stuff is very smooth, like fine plaster used for the ceilings of rooms."

Soap-suds or urine was used to make the composition of the consistency of plaster or paint.

After being applied it was covered with a sifting of powder made of " dry powder of wood ashes, mixed with the sixth part of the same quantity of the ashes of burnt bones."

This composition was recommended to cure disease, defects, and injuries of plants. It was held to be particularly valuable in promoting the healing of wounds, and was commonly used to fill cavities in trees.

Early in the history of the treatment of plant diseases, paints and washes were in general use. They were applied by means of brushes, or the plants were actually washed with a rag or sponge, so that they were very thoroughly cleaned. This practice is by no means out of date, for it is still one of the regular duties in good greenhouse management to wash many of the plants in order to keep the foliage clean and healthy. Soap or some similar substance is still generally added to the water, as was formerly done. This alkali could always be readily obtained, and as it possesses decided merit as a destroyer of certain insects, it was at a very early day regarded as a valuable remedy.

We have another interesting note in the following extract in which the destruction of the canker-worm is desired : ^

" There are several experiments I could wish to have tried, for subduing these insects : Such as burning brimstone under the trees in a calm time ; — or piling dry ashes, or dry, loose

1 Oath regarding the correctness of the directions was made at the Land Revenue Office, in Scotland Yard, the eleventh day of May, 1791.

* Samuel Deane, D.D. (vice-president of Bowdoin College), "The Newengland Farmer, or Qeorgical Dictionary, '' second edition, 1797.

sand round the roots of trees in the spring; — or throwing powdered quicklime, or soot, over the trees when they are wet; — or sprinkling them, about the beginning of June, with sea water, or water in which wormwood, or walnut leaves, have been boiled; — or with an infusion of elder, from which I should entertain some hope of success. The liquid may be safely applied to all the parts of a tree by a large wooden syringe, or squirt.

^^ I should suppose that the best time for making trial of these methods would be soon after the worms are hatched: for at that stage of their existence they are tender, and the more easily killed. Sometimes a frost happening at this season has destroyed them. This I am told was the case in some places in the year 1794."

Forsyth ^ recommended the following mixture for the destruction of aphis :

Unslaked lime k peck.

Allow this to stand three or four days, stirring two or three times per day. It was applied by means of a syringe. He recommended * the same mixture for the destruction of acarus, or red spider, but said that pure water would also answer the purpose. For plants in hothouses the use of pure water alone was advised. Against insects on melons, however, he said * that the plants should first be washed with water, and then again washed with a mixture of urine and soap-suds, using a rag. It is also stated ^ that several English nurserymen used train- [whale-] oil against coccus, or scale insects on plants. It was applied with a brush, but the author claims that it was not an efficient remedy. Nevertheless it was extensively used in some parts of England.

During the early years of this century a great many substances were recommended both in this country and in Europe for the destruction of the enemies of cultivated plants. Mention^ is made of the following articles which were to

1 William Forsyth, '* A Treatise on Culture and Management of Fruit Trees," American edition edited by William Cobbett, 1802, 178.

» J. Thacber, M.D., " American Orchardist," 1822, 104.

be used against the apple-tree borer, an insect that is designated as a " pernicious reptile " by the author. After digging out the borer, fill the cavity about the base of the tree with " flax rubbish, sea-weed, ashes, lime, searshells, sea-sand, mortar rubbish, clay, tanner's bark, leather scraps, etc." I can find no record of careful experiments having been made with these articles, and it is not improbable that some of them were recommended without actual trial, as is sometimes done even to this day, simply on the groimd that the remedy " ought " to be of value. It is also stated,^ quoting from the " Massachusetts Agricultural Reports," that Josiah Knapp, of Boston, in 1814, used air-slaked lime with success against the canker-worm. He applied it thickly about the base of the tree. Later experiments have shown that this is of little benefit in checking the ravages of the insect. The use of air-slaked lime is said ^ to have been successful in the destruction of slugs found on the foliage of fruit trees, and this is still one of the best remedies we possess. Tar water also proved to have the power of instantlykilling the slugs with which it came in contact. It was prepared by pouring water on tar and allowing it to stand for two or three days. This gave a strong infusion and was said to be very effective.

Several remedies against caterpillars are also mentioned.* " It is asserted " that spirits of turpentine, or common fish-oil, has the power of penetrating through the web made by these insects and they are killed when the liquid comes in contact with their bodies. Mr. Yates, of Albany, N.Y., made a mixture which well illustrates the variety of materials used during this period :

Wormwood 1 handful.

Rue 1 "

Virginia tobacco 2 handfuls.

Water 2 pailfuls.

Boil the herbs in the water for half an hour, strain the liquid, and it is then ready to be applied. Yates also said that if sufficient tobacco is used alone, it will answer the same purpose as the above, but not so well.

1 J. Thacher, M.D., "American Orchardist," 1822, 92. a Ihid. 107. » Ibid, 96.

Reference is also made * to some experiments of E. Perley to combat scale insects on trees. He found, after trying many substances, that the most effectual way of removing scale insects from trees was to wash them with lye, or brine. Lime could be used with the lye to advantage. The brine was made by using