AGRICULTURE Berkeley. Cal. Compliments of JOHN T. HENDERSON, Commissioner of Agriculture. Berkeley. Cat. LIBRARY COLLEGE OF AGRICULTURE THE FARMERS SCIENTIFIC MANUAL. ERRATA. Page 7— In table of Chemical Symbols, cobalt should be Co., platinum, Pt. Page 16— Carbolic acid should be carbonic acid. Page 28— In paragraph commencing Magnesia, insert as a carbonate after the word lime- stone. Page 29— Sentence beginning Alum should end, potash or ammonia. Page 38— Dicatyledonous and monocatyledonous should read, dicotyledonous and monocotyledonous. The printers made the same mistake in other places where these words occur. COMMISSIONER OF"* AGRICULTURE OF THE STATE OF GEORGIA. DEPARTMENT OF AGRICULTURE, ATLANTA, GEORGIA 1878. * 1 o*H* e^f Jambs P. Harbison & Co., Printers and Publishers, Atlanta, Georgia. INTRODUCTORY^. ' '"'- ' There has long existed among practical farmers a preju- dice against the application of science to practical agri- culture, or, as they have been pleased to call it, "book farming." This prejudice has not only retarded the pro- gress of agriculture in the South, but has prevented far- mers from seeking, through the medium of books and agricultural journals, the information so necessary to the most intelligent and profitable conduct of their peculiar business. This prejudice has not only been to a large extent over- come in Georgia, but there is a manifest thirst for a knowl- edge of science as related to agriculture. There is a spirit of inquiry among the farmers of Georgia, excited to some extent by the publications of this Department, and mani- fested in the multitude of inquiries being received at this office, which renders the publication of the following work not only appropriate, but almost a necessity. Empiricism has too long been the reproach of Southern agriculture. It is the natural outgrowth of the necessary isolation of the owners of large landed estates. There is no other occupation which naturally calls to its aid so many of the sciences as does that of agriculture. Geology, mineralogy, chemistry, botany, zoology, me- teorology, entomology, vegetable and animal physiology — all the natural sciences — reflect light upon agriculture as a pursuit, and hence the relations of these sciences to agri- culture constitute appropriate fields of study for those who derive both pleasure and profit from the cultivation of the soil. The farmer has to deal with soils and manures, with plants and animals, with insect friends and enemies, with temperature and moisture, and must use in his daily work various mechanical appliances, both simple and compound. The character, treatment, needs and mutual relations of all 369063 4 ^ DEPARTMENT OF AGRICULTURE — GEORGIA. [290] of these, should be understood by the advanced agricult- uralist. The object of this work is : 1st. To present, as briefly as is consistent with perspicu- ity, such information as will aid the farmers of Georgia in more thoroughly understanding the great leading principles which underlie the whole field of progressive agriculture. 2d. To stimulate the spirit of inquiry which now per- vades the agriculturists of the State. In the scope allotted to this pamphlet it is impossible to do more than whet the already growing appetite for knowl- edge, by presenting to the intellectual palate a few savory morsels, gleaned from the field of science, with the hope of stimulating such thought and research on the part of the farmers of Georgia, as will bring forth fruit both abun- dant and ripe, for future gleaners in the field of successful agriculture. The losses annually sustained by the farmers of the State, in consequence of ignorance of the plainest teachings of agricultural science, afford ample justification for the publi- cation of this Manual in which the difficult task is at- tempted of so popularizing the teachings of science, as ap- plied to agriculture, that the unscientific, practical farmer may readily appropriate to his own use the results of scien- tific research. No claim to originality is made. On the contrary, the material has been compiled from standard authors, con- densed, simplified, and interwoven with illustrations and practical suggestions, applicable to our surroundings. Those who wish to pursue still further the study of the subjects, that have been merely touched upon in this pam- phlet, are referred to Scientific Agriculture — Dr. E. M. Pendleton ; How Crops Grow and How Crops Feed — S. W. Johnson ; Talks on Manures — Joseph Harris ; Land Drainage — Klippart ; and Structural and Systematic Botany — Professor Asa Gray. [291] SCIENTIFIC MANUAL. 6 CHAPTER I. GENERAL CHEMISTRY. Definition of Terms. The natural sciences relate to the laws which govern the different departments of nature. The following are of es- pecial interest to the agriculturist : Botany. — The science of plants, embracing an account of their properties, structure, classification, and the laws which govern their growth and development. Zoology. — The science of animals, their characteristics and relations to each other. Entomology. — The science of insects. Mineralogy. — The science of minerals. Geology. — The study of the earth, its age and forma- tion ; the character of its rocks and the soils derived from them ; and the occurrence of its minerals. Meteorology. — The science of the atmosphere, and its various phenomena. Chemistry. — The study of the composition and prop- erties of all materia] objects, including rocks, minerals, soils, plants and animals — everything, visible and invisible, in earth, water and air. These will be treated in this work only so far as they relate to agriculture. Chemistry teaches that all things in nature, animate and inanimate, solid, liquid and gaseous, are either simple sub- stances, or are formed by the union of two or more simple substances, to each of which the name of element 'is given. Each element is entirely distinct from the others, has its own peculiar properties and characteristics, and cannot be divided into two substances having distinct properties, To illustrate, lead is an element and cannot, by any known means, be divided into any other substances, while red lead is a compound of lead and oxygen By the use 6 DEPARTMENT OF AGRICULTURE GEORGIA. [292] of certain means the two elements can be completely sep- arated. Gold, silver, copper and tin are also elements. There are only about sixty-six simple elements known to the chemist. Of these, and their various combinations, all matter, solid, liquid and gaseous, is composed. When an element is found occurring naturally, and not combined with another, it is said to exist M free in nature." Nearly all of the substances composing the vegetable, animal and mineral kingdoms, are combinations of two or more elements. Matter is indestructible. The apparent destruction of a substance is merely the breaking up of its elements and the formation of new compounds. Many of these elements have an attraction or affinity for each other; the rusting of iron is merely the union of iron with oxygen which exists in air and water. Heat, light and electricity aid the union of these elements. It has been found that these elements are governed by laws in their union with each other, and that these laws, like those in other departments of nature, are uniform and constant in their operation. One of these laws is, that elements always unite with each other in certain proportions by weight and volume ; should there be an excess of one element present, it will remain uncombined. The elements are divided into various classes, viz : those which exist as gases only, those which are liquid, and those which are solid. Symbols. — Each element is designated by a letter, or let- ters, taken from its Latin name. When two letters are used, the first is a capital. Thus, the symbol of iron is Fe. Substances composed of two or more elements are designated by the grouping of the symbols of its different elements. Thus, hydrochloric or muriatic acid is composed of hydrogen and chlorine. The symbol of hydrogen is H., [293] SCIENTIFIC MANUAL. that of chlorine is CI. f hence the symbol of the acid is HCL Very often one part, by weight, of an element unites with two or more parts of another. This is expressed by a figure placed at the right and a little below the symbol. For in- stance, H2S04 represents sulphuric acid of commerce, which is composed of two parts of hydrogen, one of sul- phur, and four of oxygen. Below is a list of elements of the most practical value. The list embraces the most important elements to be considered in this work. The symbol of each is given: NON- METALLIC ELEMENTS. Iodine ..I Sulphur S r H y drogen H Oxygen O Gases. 38] ten, which being deposited upon the stigma of the pistil fertilizes the ovule or embryo seed at its base. Stigma The pistil, represented by Fig. 13, is composed of four principal parts : The stigma, which is an enlarged, porous, moist, roughish and naked style, body (having no skin covering like the other parts) terminating the style, which connects it with the ovary at the base of the pistil; within the ovary or seed pod, is the ovule or em- 0vary- bryo seed. The pollen grains falling from the anther of the stamen on the stigma, ovule, or conveyed to it by the winds or insects, in some way not yet fully understood, exerts an influence upon the ovule or embryo seed, which re- sults in the production of seed. It is not deemed necessary to enumerate in detail, the different forms which flowers assume, the object being simply to convey an idea of the essential parts of flowers, in connection with the process of fructification and reprq- duction. To still further illustrate these, Figure 14 represents a vertical section of a cherry blossom, in which are shown the sepals, petals, stamens, pistils, ovary, and ovule. This is a complete flower, but it will be observed that the sepals, petals and stamens, all branch out from the margin of .a thickened cup, which is only the base of the floral envelope which embraces both calyx and corolla, which are the basis of the flower-vase, one of the principal offices of which is to protect the essential organs, the stamens and Pistil Magnified. Fig. 13. [339] SCIENTIFIC MANUAL. 53 Section of cherry blossom, showing every part of the flower. pistils. The sepals, all taken together, form the calyx; the petals, collectively, form the carolla. The Circulation of Sap will now be considered only so far as a knowledge of it may be thought useful to the far mer. All of the functions of vegetable nutrition may be expressed in three words, viz : imbibition, assimilation Figure and growth. Imbibition takes place through the root-hairs, the leaves and green parts of the bark, principally by osmose, but to some extent by capillary attraction, and is confined to liquids and gases, the former being derived chiefly from the soil, the latter principally from the air. All of the ash element (that which remains when vegetable matter is burned in the air.) of plants is imbibed in solution in water by the 'roots, as well as some of the organic ele- ments which pass off into the air when the plant is burned. The importance of this root action will be appreciated when it is remembered that plants, in the fresh state, con- tain from 70 to 90 per cent, of water. The following tables, taken from Johnson's "How Crops Grow," show the percentages of water in some common agricultural products, fresh and air-dried. These percent- ages vary in different plants of the same species, and in the different parts of the same plant. The amount varies also at different stages of growth, with the amount of moisture in the soil in which it grows, and the humidity of the air by which it is surrounded. DEPARTMENT OF AGRICULTURE — GEORGIA. [340] WATER IN FRESH PLANTS. Per Cent. Meadow Grass 72 Red Clover 79 Maize, as used for fodder. . 81 Cabbage 90 Potato Tubers 75 Sugar Beets 82 Carrots 85 Turnips 91 Pine Wood 40 WATER IN AIR-DRY PLANTS. Per Cent. Meadow Grass (Hay) 15 Red Clover Hay 1 Pine Wood 20 Straw and Chaff of Wheat, Rye, etc 1 Bean Straw 18 Wheat, Rye, Oat, (kernel) 14 Maize (kernel) 12 Since no mineral substance can be taken into the plant except in a state of solution, it is not only necessary that there should be an abundance of moisture in the that the mineral elements of plant-food shall be in a solu- ble condition before they can be made available to the plant. The water in the soil enters the absorbing surfa^ ces of the roots of %he plants mainly by osmodic imbibi- tion, certain vegetable acids being expelled by exosmose from the root-hairs, which act chemically upon the mineral substances of the soil, as is plainly shown by the etching of smooth marble by the roots of plants which rest upon it during their growth. Capillary force may also partici- pate in this imbibition, when a rapid evaporation of watery vapor is progressing from the surfaces of the leaves. This liquid, (soil water,) freighted with unorganizable or crude plant-food, passes by osmodic action from cell to cell, until millions of these receptacles have been traversed in its passage to the leaf where, spread out under the in- fluence of sunlight, it is assimilated — converted into more condensed organizable plant-food by the evaporation of watery vapor, and the exhalation of oxygen. The contents of the cells of the leaves being thus ren- dered more condensed, the prepared sap passes down- ward from cell to cell, is appropriated to the growth of the plant by cell division over the entire growing surface of the plant, thus perpetuating the process so long as the [341] SCIENriFIC MANUAL. 55 surrounding circumstances of warmth and moisture are favorable. Leaves imbibe from the air, carbonic acid gac, which is decomposed under the influence of sunlight into its ele- ments, carbon and oxygen, the former retained, and the latter, to a large extent, exhaled into the air again. During the night carbonic acid is exhaled, and oxygen re- tained. The volume of oxygen exhaled during the day is about equal to that of the carbonic acid imbibed during the same time. Sunlight is necessary for the healthy development of vegetation, as is shown by the white appearance of potato sprouts which grow in dark cellars. In cases of drouth the mineral food held in solution by the liquid imbibed by the roots is too highly concentrated, and often produces injurious effects upon vegetation apart from those resulting from drouth proper. This is fre- quently seen where highly ammoniated commercial fertili- zers have been applied in large quantities in the drill, to summer crops. CHAPTER III. CHEMICAL COMPOSITION OF PLANTS. The whole physical world is divided into organic and in- organic substances. The first embraces all bodies which have resulted from life, and includes both the vegetable and animal kingdoms. The second embraces all bodies not the result of life, as well as the remains of organic bodies reverted by complete decomposition to mineral form. All organic substances are composed of volatile and fixed, or ash, ingredients. 56 DEPARTMENT OF AGRICULTURE — GEORGIA. [342] The volatile part, which constitutes on an average about 95 per cent, of the whole plant, is composed of carbon, oxygen, hydrogen and nitrogen, with very small quanti- ties of sulphur and phosphorus. They are called volatile elements because they are driven off and mingled with the atmosphere when the organism is burned in the open air. The ash elements which remain after the burning as solids, are chiefly phosphorus, sulphur, silicon, chlorine, potassium, sodium, calcium, magnesium, iron and manga- nese, and also small quantities of oxygen, carbon and nitrogen. A few other elements are found in very small quantities — too small to require notice here. The elements are given in the above enumeration, but they are usually taken into the organism, and appear in the ash as com- pounds. These elements, and their principal compounds of any importance in connection with agriculture, have already been described. These various substances, volatile and fixed, enter into the same plant in a uniform ratio to each other, but in very differ- ent percentages. The importance of any constituent, how- ever, bears no relation to the per cent, in which it is found in the plant. In one sense they are all of equal importance, since the plant cannot attain to full development without the presence of all of these elements, which naturally enter into its composition, in the necessary ratio to each other. Though the ash elements occur in relatively very small quantity, they are essential to the perfect development of the plant, and are, together with nitrogen, the first which need to be artificially supplied to the soil. The atmos- phere affords an inexhaustible source of the prominent volatile elements of plant food. Wolff and Knop give the following percentage from all the trustworthy analyses made of agricultural plants— all of them air-dried, except the last : Organic Matter. Ash. 79.9 5.8 83.3 2.5 80.2 5-4 77.7 \7 13.4 18.8 • -Pendleton. [343] SCIENTIFIC MANUAL. 57 Water. Average of all the grasses 14.3 Average of grains and seeds 14.2 Average of straw 14.4 Average of chaff and hulls 13.7 Average of roots and tubers 85.7 Average of green fodder, 79.5 —Scientific Agriculture. These analyses show how small is the per cent, of ash ingredients in plants in proportion to the volatile part. Nearly the whole of the volatile part, except the water and ammonia, is derived from the atmosphere, while the entire ash is derived from the soil. The following tabular view of the relations of atmos- pheric ingredients to the life of plants, given by Prof. John- son in "How Crops Feed," page 98, presents the subject in a condensed form : TABULAR VIEW OF THE RELATIONS OF THE ATMOSPHERIC IN- GREDIENTS TO THE LIFE OF PLANTS. Oxygen, by roots, flowers, ripening fruit, and by all growing parts. Carbonic Acid, by foliage and green parts, but only in the light. Ammonia, as carbonate, by foliage probably at Absorbed . all times. by Plants. » Water, as liquid, through the roots. Nitrous Acid, \ united to ammonia, and dis- Nitric Acid, J solved in water through the roots. Ozone? | Uncertain. Marsh Gas? J Not absorbed f Nitrogen. by plants. \ Water in state of vapor. ' Oxygen, ) by foliage and green parts, but only Ozone, j in the light. Exhaled Marsh Gas, in traces by aquatic plants? by Plants. { Water, as vapor, from surface of plants at all times, | Carbonic Acid, from the growing parts at all (^ times. DEPARTMENT OF AGRICULTURE — GEORGIA. [344] In speaking of the chemical composition of plants, the ultimate constituents or elements will be seldom mentioned, since they are never taken up by plants in their elementa- ry forms, but as proximate principles, or compounds. To illustrate : Carbon is taken into the plant in the form carbonic acid gas ; phosphorus, as phosphoric acid ; nitro- gen, as ammonia, nitric acid, etc. The proximate organic principles are divided into "carbo- hydrates, albuminoids, vegetable acids, vegetable oils, al- kaloids, and coloring matters." Carbo-hydrates, so named from being composed of carbon hydrogen and oxygen, are subdivided into woody fibre, starch, sugar, gums, and jellies, all of which are objects of interest to a greater or less extent to the agriculturist. Cellulose, the principal constituent of woody fibre, forms a very large part of all vegetable structure, serving as the framework of the organism, and especially of the cell walls. ''Cellulose exists in various vegetable matters, when air- dried, in the following proportion : Per cent. Per cent. Potato tuber 1.1 Clover hay 34.0 Wheat kernel 3.0 Maize kernel..... 3.5 Barley kernel 8.0 Oatstraw 10.3 Maize cobs 38.0 Oat straw 40.0 Wheat straw.... 48.0 Rye straw 54.0 — Scientific Agriculture.— Pendleton. Lignin is more dense, contains more carbon, and is less digestible than the cellulose. Starch is very abundant in many vegetables, and espe- cially so in many seeds and tubers. It is found within the cell-walls in very minute grains. It is made from various grains and tubers, by first grating, grinding, or otherwise pulverizing the substance, so as to break the cell-walls, when the powder or flower is washed with water, the starch grains held in suspension allowed to settle, the water poured off, and the deposited starch dried. Or, the albu- SCIENTIFIC MANUAL. 59 minoids may be dissolved out by a weak solution of caus- tic soda before washing. Cellulose and Starch are identical in chemical composi- tion ; each having : Carbon 44.44 Hydrogen ,« 6.17 Oxygen 49.39 100.00 Dextrine, also identical in chemical composition with celullose and starch, is found in old potato tubers and the un- ripe wheat plant. It may be made artificially from starch, and is used extensively \~ the arts, especially in printing calicoes. In baking breaa, s oortion of the starch is con- verted into dextrine, the latter sometimes amounting to as much as ten per cent. The gums constitute an important product from many plants, and are extensively used in commerce. They are convertible into grape sugar by long boiling in water. Von Bibra gives the following percentage of gum in various substances air- dried: Wheaf kernel 4.50 Wheat flour, 6.25 Rye flour. 7.25 Barley flour 6.33 Oatmeal 3.50 Rice flour ..2.00 Wheat bran 8.85 Rye kernel 4.10 Millet flour 10.60 Corn meal (maize) , 3.05 Buckwheat flour 2.85 Spelt flour 9 2.48 Pendleton. Sugar occurs in the several forms of cane sugar, fruit sugar, grape sugar and milk sugar. 60 DEPARTMENT OF AGRICULTURE — GEORGIA. [346] Cane sugar, saccharose, derived principally from sugar cane, sugar beet and the sap of the sugar maple, that from the sugar cane constituting the great bulk of the sugar of commerce. Pure cane sugar, free from water, consists of: Carbon 44.92 per cent or 12 atoms Hydrogen 6.11 " " " 10 atoms Oxygen 48.97 " " " 10 atoms The following table will show the average percentage of saccharose in the juice of several plants ("How Crops Grow," p. 13.): Sugarcane 18 per cent Peligot. Sugar beet , 10 per cent Peligot. Sorghum 9J per cent Goessman. Indian corn in tassel 3J per cent LudersdofT. Sugar maple sap 2J per cent Liebig. Red maple 2J per cent Liebig. Saccharose is twice as sweet by weight as glucose. Grape sugar or glucose is found in the juices of many plants, in honey, etc. In the malting of grain a portion of the starch is converted into glucose. It is composed of carbon, 40.00, hydrogen 6.Q, and oxygen 53.33. Frutt sugar or fructose, though identical with glucose in chemical composition, is much sweeter, does not crystal- lize, and is found generally combined with other sugars, in honey, molasses, and fruits. Milk sugar — Lactose, is found only in the milk of ani- mals, and is prepared from the whey of milk in some coun- tries. ' Its chemical composition in 100 parts is: carbon, 42.10; hydrogen, 6.40; and oxygen, 47.00. Von Bibra found saccharose, glucose or fructose in the following percentages in the flour of different grains : Per Ct. Wheat flour 2.33 Wheat bran 4.30 Rye flour ....3.46 [347] SCIENTIFIC MANUAL. 61 Pet Ct. Rye bran 1.86 Corn meal 3.71 Barley meal 3.04 Barley bran 1.90 Oat meal 2.19 Rice 0.39 Buckwheat meal 0. 91 — (Scientific Agriculture — Pendleton. Alcohol is produced from sugar, by fermentation, in the presence of water, at a temperature of from 60° to 90° Far. It is also produced from plants, seeds and tubers con- taining starch, the latter being first converted into sugar, and then into alcohol. Cellulose •, starch, sugar, dextrine and gum are mutually convertible in nature, and to a considerable extent in the laboratory. "Thus in germination, the starch of the seed is converted into dextrine and glucose, and in this form passes into the embryo to nourish the plantlet. Here, again, it changes into cellulose and starch. In the sugar beet (which is destitute of starch, but contains 10 to 14 per cent, of sugar), in certain diseased conditions, the su- gar is transformed into starch." The principal vegetable acids are, malic, tartaric, citric, oxalic, tannic, acetic, vinegar and prussic. Malic acid is found in various fruits, deriving its name from Malum, the Latin for apple. It is never found pure in nature. Tartaric acid is found in the grape, combined with potash, and in the fermentation of wines is deposited as tartrate of potash. From this salt purified, the cream of tartar of commerce is derived. It is used as a medicine, and the acid is an ingredient of Seidlitz powdens. Citric acid is found in the juice of the lemon, lime and other fruits of the citron family. Its compound with iron, citrate of iron, is used in medicine. 62 DEPARTMENT OF AGRICULTURE — GEORGIA. [348] Tannic acid is found in the bark and leaf of the oak and other trees and plants. Its principal use is in tanning leather. It is also used with copperas in making ink. Oxalic acidis found in considerable quantity in the sorrels. It is a powerful acid, having a remarkable affinity for lime, even displacing sulphuric acid. Hence an application of lime is beneficial to the lands of Southern Georgia, on wnich the sorrel grows, its effect being to neutralize this and other injurious vegetable acids. The presence of sorrel in considerable quantity may be regarded as an indication that lime is needed. Acetic acid is the sour principle of vinegar, which is an impure form of acetic acid, resulting principally from the fermentation of the juices of fruits, but is also pro- duced from any liquid containing sugar, by the use of a ferment, by the oxidation of alcohol, from infusion of malte and from a mixture of starch and yeast. Mother of vinegar, which consists of an aggregation of microscopic plants (ulvina aceti) is produced in acetous fermentation which it not only facilitates, but probably causes. Vinegar is made rapidly from fermented or fermenta- ble liquids, by passing them repeatedly through oaken bar- rels filled with beech shavings, previously steeped in strong vinegar, increasing the temperature of the liquid at each filtration. Vinegar made from wine or cider is most highly esteemed for domestic uses. Prussic acid is found in a very dilute state in the bark and leaves of the cherry, and peach, and also in the kernels of most stone fruits. It is present in considerable quantity in the bark of the wild cherry, the medicinal properties of which are attributed to the influence of this acid. Vegetable oils are divjded by distinct characteristics into fatty or fixed oils, and essential or volatile oils. These exist as minute, transparent globules in the cells of plants, and may generally be extracted by simple pressure. In the [349] SCIENTIFIC MANUAL. 63 common bayberry and the tallow tree of Nicaragua, however, the fat, being solid at ordinary temperatures, requires heat for its extraction. The principal source of commercial vegetable oils, are the seeds of flax, cotton, hemp, sunflower, colza, pea-nut, butter nut, the castor bean, etc., in which the per cent, of oil ranges from 10 to 70. The principal dif- ference between the fatty and the volatile oils as indicated by their names, is found in the non-volatile character of the former, and the volatility of the latter. Fatty oils dropped upon paper leave a grease spot, while the volatile oils en- tirely evaporate, leaving no trace of grease. "The proportion of fat in certain vegetable products is given by Wolff and Knop, as follows : Maize fodder (green) 0.5 Indian corn 7.0 Redclover (green) 0.7 Wheat 1.5 Cabbage 0.4 Rice 0.5 Pea-fodder (dry) 2.0 Oats 6.0 Clover hay 3.2 Peas , 2.5 Wheat staw. 1.5 Barley 2.5 Average of all the grains. 2.6 Winter rye 2.0 Potato (Irish) 0.3 Pumpkin 0.1 Turnips 0.1 Beet .*. 0.1 The Albuminoids or Protein Bodies are classified in three groups. The type of the first is albumen, which is found nearly pure in the white of an egg ; of the second, fibrin, represented by animal muscle; of the third, casein, or the curd of milk. Animal Albuminoids differ very little from the vegetable from which they are primarily derived. In both the living or undecayed vegetable and animal matters they are prin- cipally soluble in water, but are very readily rendered in- soluble by coagulation. They differ from the carbo-hydrates in having in addition to carbon, hydrogen and oxygen, 15 to 18 per cent, of ni- trogen, some sulphur, and often a small amount of phos- phorus. Together they constitute in plants the whole 64 DEPARMENT OF AGRICULTURE'— GEORGIA. [350] volatile part of vegetation, and furnish the fat and flesh producing principles of animal food. A knowledge of the relative proportion of these two groups of plant constituents is Of prime importance to the farmer, since the efficacy of the food of animals depends, in a large measure, upon the proper combination of the fat and flesh forming principles. This will be more fully discussed under the head of Plants and their products as food for animals. Vegetable Albumen may be obtained by heating nearly to the boiling point the liquid which is decanted from potato starch, as previously directed, collecting the coagulum which forms on the surface, and boiling it successively with alcohol and ether to remove fat and coloring matters. A substance is thus formed resembling very closely the albu- men of eggs. Albumen may be extracted from the flour of wheat, oats, rye, or barley, by similar treatment of water in which it has been agitated for some time. Vegetable fibrin may be obtained from wheat-flour, by kneading thcdough for some time in a vessel of water, the first product being gluten, from which the vegetable fibrin may be dissolved out by alcohol, which latter may be re- moved by evaporation, leaving nearly pure fibrin. It is soluble in hot alcohol, very slightly In cold alcohol, and not at all in water. Vegetable casein occurs in peas and beans, as well as in the seeds of other leguminous plants, amounting in some to from 17 to 19 per cent. It very closely resembles ani- mal casein as found in milk. It is found in smaller per- centages in other seeds and in tubers. The Chinese make a vegetable cheese, called Tao-foo, by boiling peas to a pulp, straining the liquid, coagulating it with gypsum, and then treating the curd thus obtained in the same manner as milk-cheese is treated. Prof. Johnson gives, in "How Crops Grow," page 102, the 351] SCIENTIFIC MANUAL. 65 following table, showing the chemical composition of some of the principal animal and vegetable albuminoids, which will convey to the reader a clear idea of the character and value of this group of substances : COMPOSITION OF ALBUMINOIDS Car- bon Animal Albumen , Vegetable Albumen Blood Fibrin Flesh Fibrin Wheat Fibrin Animal Casein Vegetable Casein Gluten-Casein ) Gliadin* J- Wheat Mucedin ) Hydro- gen. Nitro- gen Oxy- Sul- gen. phur. 1 0 0.9 l.z 1.1 LO 1 0 0.5 0.8 OS 0.9 53.5 7.0 155 22.4 53.4 7.1 15.6 23 0 52.6 7.0 17.4 21.8 54.1 7.3 16.0 21.5 54.3 7.2 16.9 20 6 53.6 7.1 15.7 22.6 50.5 6 8 18.0 24.2 51.0 6.7 16.1 25.4, 52.6 7.0 18.1 21.5 54.1 6.9 166 21.5 * Gliadin and Mucedin are two albuminoids which exist in crude wheat gluten. Since animals have, as far as known, no power of produc- ing the albuminoids, which constitute so large a part of their blood and flesh, but derive them entirely from plants, it is important for the fanner to acquaint himself, not only with the chemical composition of the cultivated plants, but also with the means of increasing, by cultivation and fer- tilization, the percentage of these important substances, by stimulating the production of those parts of the plants which are richest in them. It is important also that he should know the ratio, exist- ing in different plants, between the carbo-hydrates, or fat and heat producing principles, and the albuminoids or flesh and muscle producers, that he may know what kind of food to use, to accomplish given results in feeding stock, whether the object be the production of fat, the maintenance of a unifo'rm condition of muscular development, or to encour- age the development of a well proportioned muscular frame in young animals. These objects are usually best accomplished by a combination of different foods, as will be more fully explained under the head of Plants and their products as food for animals. The following table from Johnson's "How Crops Grow/' 5 66 DEPARTMENT OF AGRICULTURE — GEORGIA. [352], gives in a condensed form the percentages of albuminoids in the principal agricultural plants. average quantity of albuminoids in various vegetable products: Indian corn fodder, green. ...... .1. Beet tops, green 1. vJarrot tops, green 3. Meadow grass, green 3. Red clover, green 3. White clover, green 4. Turnips, fresh 1. Carrots, fresh ... 1. Potatoes, fresh 2. Corn cobs, air dry. . . 1. Straw of summer grain, air dry. . .2 Straw of winter grain, air dry. . .3. Pea straw, air dry 7. Bean straw, air dry. 10.2 ^Meadow hay, air dry 8 5 Red clover hay, air dry 13.4 White clover hay, air dry 14.9 Buck wheat kernel, air dry 7.8 Bailey kernel, air dry 10.0 Indian corn kernel, air dry 10.7 Rye kernel, air dry 11.0 Ont kernel, air dry 12.0 Wheat kernel, air dry 13.2 Pea kernel, air dry 22.4 Bean kernel, air dry. -24.1 Lupine kernel, air dry 34.5 Ihe ash elememts which remain as solids when plants are burned in the open air, also called the mineral or inorganic part of the vegetable structure, though constituting a very small part of plants, are nevertheless of prime import- ance to the vegetable economy, and hence to the agricul- turist. The following table shows the principal elementary sub- stances, found in the ash of plants, and the compounds which they form with oxygen, or with each other. With the exception of sulphur, none of these elements are found in nature, but they exist in the soil and in plants as com- pounds with oxygen, or with each other. Since these com- pounds are not found in the atmosphere, they must be taken into the plant through the roots, and must, therefore, be present in the soil in an available form to secure the normal development of plants. Other elementary bodies occur in some plants in very small quantities, but have no important relation to the general vegetation of the farm. 353] SCIENTIFIC MANUAL. 67 TABLE OF ASH ELEMENTS WITH THEIR COMPOUNDS WITH OTHER SUBSTANCES. Name. In combination with Forming. Chlorine.... Metals Chlorides. Iodine Metals Iodides. r Metals Sulphurets. Sulphur... 1 Hydrogen.... Sulphuretted Hydrogen.* (Oxygen Sulphuric Acid. Phosphorus Oxygen Phosphoric Acid. / Oxygen Potash. *"\ Chlorine Chloride of Potassium. {Oxygen Soda. Chlorine Chloride of Sodium or > Common Salt. / f Chlorine Chloride of Calcium. " \ Oxygen. Lime. Magn esium Oxygen .Magnesia. Aluminum Oxygen Alumina. Silicon Oxygen Silica. Iron and \ ....Oxygen ( Oxides. Manganese i ....Sulphur I Sulphurets. Potassium. Sodium.... Calcium.... -Called also Hydro-sulphuric Acid, t Agricultural Chemistry . — Johnson. Since plants can ti?ke up no solid matter, however finely divided, all of these substances must be either in a soluble condition in the soil, or readily rendered so by reagents existing in the soil. As their character, and the sources of each, have already been given, their further discussion will be resumed under the heads of Plant Fertilization, Soil Fertilization, and Fertilizers, CHAPTER IV. PLANT FERTILIZATION. There are two methods of ascertaining what elements of food different plants require: 1st. By the analysis of the plants themselves, the chem- 68 DEPARTMENT OF AGRICULTURE — GEORGIA. [354] ist learns what they contain, and in what ratio the different elements enter into their composition. 2d. By experiments in growing plants under circum- stances in which all the conditions of growth are known, and in which the effect of different elements of plant- food can be definitely ascertained. Indeed, plant analysis, soil analysis, and experiment, are all employed Li conjunction, to ascertain the needs of different plants. Seeds are planted in soils of known composition, to which different elements of plant-food, in various quanti- ties and ratios, are added, and the results compared. Science is thus enabled to know, not only what kinds of food are required for different agricultural plants, but the proportions in which they unite in each. By reference to the Tables in the Appendix, it will be seen that in the ash of most of our cultivated plants, potash and phosphoric acid play a conspicuous part. Not only do these enter largely into the ash of these plants, but it is a well established fact that they are earlier exhausted from the soil than any other mineral elements, and hence must be supplied artificially by the farmer. These, together with nitrogen, are the principal constitu- ents necessary to be artificially supplied on most soils, though soda and lime are often applied with satisfactory results. As shown by the Tables, tobacco is a large consumer of all of the principal elements of mineral plant-food, and is, consequently, the most exhausting crop grown in the South. While the analysis of plants indicates very accu- rately the kind and per cent, of the constituents which enter into the organism, a knowledge of the character of the soil, and feeding capacity of the plants, is necessary to determine to what extent these constituents should be artificially applied. In plant fertilization, the farmer aims to supply each crop with just those constituents in kind and quantity which f [355] SCIENTIFIC MANUAL. 69 are supposed to be necessary to the production of the maximum crop. These constituents are varied in kind, quantity and ratio, to suit the requirements of different plants, and are also modified by circumstances of soil, tem- perature and supply of moisture. To illustrate : the tobacco planter requires a fertilizer richer in potash than in phosphoric acid, with a liberal percentage of ammonia, lime, magnesia, chlorine, and soda, unless these ingredients already exist in abundance in the soil. The cotton planter requires more phosphoric acid than potash, which together, with ammonia, are the princi- pal^ingredients of the fertilizers usually applied to cotton. Plant fertilization is generally practiced in Georgia, and in all other States where land is cheap, and large sur- faces cultivated. It is a temporary resort for immediate results ; and though securing profitable crops, seldom per- manently improves the quality of the soil, unless combined with judicious and systematic rotation of crops, involving both protection from summer suns, and a return to the soil of a large part of the vegetable matter produced. It is the most economical method of fertilization, where immediate returns are sought, since the plant-food is applied in such mechanical and chemical condition, and in such proximity to the roots of the plant, as to be promptly available, and thus returning principal and interest in the first crop, under favorable meteorological conditions both as to tem- perature and moisture. In plant fertilization the manure is applied in the hill or drill, the method usually employed in Georgia, so that the first roots put forth reach the ma- nure, and thus give the plant an early, vigorous start. This effect has been particularly marked in North Georgia, in pushing forward the cotton plant and hastening its ma- turity, in advance of early frosts. Indeed, this system of plant fertilization has extended the area of profitable cot- ton culture about fifty miles north of the original limit, since its effect is to practically lengthen the season of *: 70 DEPARTMENT OF AGRICULTURE — GEORGIA. [356] growth about one month, by causing the plant to mature its fruit about a month earlier than that cultivated without manure in the drill. A similar advantage is realized in the original cotton belt, in enabling the planter to gather his crop in better condition, and before the weather grows too cold for expedition in the tedious process of cotton picking. Indeed, before the present system was adopted, more cotton was picked in January than is gathered now in December. The organic constituents of plants, with the exception of nitrogen, are supplied in sufficient quantity from the atmosphere, which is beyond the control of man. It is now universally agreed by scientists who have investigated the matter, that carbon, which forms so large a part of vegetation, is derived from the air, in combination with oxygen, as carbonic acid, and hence it is not necessary for the farmer to apply carbon to the soil as plant food. There are elements of plant-food, however, which the farmer not only may, but in many instances must, apply to the soil to secure remunerative crops. The principal of these are nitrogen, phosphoric acid and potash, and on some soils, and for some plants, lime, magnesia and soda ; the last three being generally present in sufficient quantity in the soil for most plants. The fact, however, that some of these elements are more important to man, on account of the necessity of their artificial supply, does not imply that one is more important in plant nutrition than another. Each is equally important to the plant to the extent to which it enters into its composition, since the plant can- not be perfectly developed without the proper combination of its chemical constituents. In the entire absence of phosphoric acid, perfect seed cannot be formed ; without carbon, neither woody fibre, starch, nor sugar can be pro- duced. The analysis of an entire plant shows the percentage and ratio in which each constituent enters into its compo- [357] SCIENTIFIC MANUAL. 71 sition ; and taking into consideration the character of the soil to be planted, the nature and analysis of the plant to be cultivated, and the fact that the so-called organic ele- ments, except nitrogen, are supplied by the air, the farmer may supply the mineral ingredients in quantity and ratio necessary to the production of a given crop. Prof. Levi Stockbridge, of Massachusetts, has reached some remarkable results by experiment on different crops, in which he predicted beforehand the increased produc- tion, as the effect of the fertilizers applied. Some of his results are very remarkable, and show a wonderful triumph of science, as applied to agriculture. His experiments, conducted for several years, illustrate two important facts, viz.: that potash, nitrogen and phos- phoric acid are generally the only elements of plant-food necessary to be added artificially to the soil, for the pro- duction of our agricultural plants, (except, perhaps, tobac- co, which requires more magnesia than is usually found in soils.) and that by the application of these three elements, in an absolutely soluble condition, in the ratio to each other in which analysis shows them to enter into particu- lar plants, a given number of bushels or pounds of these particular plants may be produced, within certain yet un- known limits, in a measure proportionate to the quantity of the fertilizer applied. A few out of the number of experiments conducted, either by himself or by others under his direction, with uniformly satisfactory results, will suffice to illustrate the method pursued and the results attained. Two equal plots at the college farm were planted in corn, and treated alike in every respect, except that one had no manure, while enough potash, phosphoric acid and nitrogen, mixed in the proper proportion, and used in suf- ficient quantity to make twenty-five bushels of corn, with the natural proportion of stalks, were applied to the other, with a small surplus, which he supposed the roots of the 72 DEPARTMENT OF AGRICULTURE — GEORGIA. [358] plants would not get the first year. The plot without ma- nure yielded thirty-five bushels, and the manured plot yielded sixty-four and four-tenths bushels, or four and four-tenths bushels more than were required. He sent, the same year, the same quantity of fertilizer to Mr. Hurd, at Hadley, in the same State, stating that it would give an increase of twenty -five bushels over the production of the unaided soil, which was very poor. The unmanured plot produced eighteen bushels, the manured plot forty eight — five more than was predicted. Concluding, therefore, that the surplus application was not necessary, he applied the next year just the quantity thought necessary to give fifty bushels more than the production of the soil without ma- nure. The result was that the unmanured plot produced thirty-four bushels to the acre, while the manured plot gave 83.28 bushels to the acre. Similar experiments were conducted with potatoes, oats, hay and beans, with correspondingly satisfactory results. Not only so ; but the same plots planted the second year, gave a large increase over the unmanured plots ; showing that the effects of the manure continued through the sec- ond year. These experiments have not been conducted sufficiently long to establish the principle, but the results thus far justify further experiment on the same line. While plant fertilization alone generally gives satisi'acto- ry results, its effects are much more satisfactory when used in connection with soil fertilization, especially when green manuring is resorted to as a means of soil improvement. I CHAPTER V. SOIL FERTILIZATION. This, though embracing plant fertilization, and having for its ultimate object the supply of food for plants, differs from it in several material respects. [359] SCIENTIFIC MANUAL. 73 One is special, direct and partial, and designed to affect a particular crop, while the other is general, indirect, and designed to permanently improve the soil, and supply nour- ishment to more than one generation of plants. One sup- plies just those elements of plant- food in ratio to each other, and in aggregate quantity sufficient to nourish par- ticular plants ; the other supplies all the elements of plant- food to the soil as a reservoir from which any plant may select the particular elements necessary for its nutrition. One is temporary and looks to immediate returns — the other is more permanent, improving the capital invested in land, and increasing the returns through a series of years. As population becomes dense, and a higher rate of pro- duction is rendered necessary for its support, as well as to insure a reasonable per cent, upon the enhanced value of lands, soil fertilization is combined with plant fertilization to insure both prompt and continuous returns. THE MEANS USED. To secure the permanent improvement of a soil, it must not only be abundantly supplied with the various elements of plant-food in forms either available or readily rendered so, but the mechanical condition must be such as to afford the free expansion of the roots of plants, and to freely ab- sorb, and retentively hold, moisture and ammonia. It is, therefore, necessary to supply three classes of sub^ stances to the soil to compass these ends, viz : actual plant- food, chemical agents, and mechanical agents. Actual plant-food, or fertilizers proper, embrace all the mineral elements of plant-food, and one volatile — nitrogen. Phosphoric acid and potash are the only mineral ingre- dients which are so far exhausted as to require artificial ap- plication to most soils, though soda, lime, magnesia, and, for some plants, chlorine in small quantities are sometimes added. Lime, which acts in the triple capacity of fertilizer, chemical agent, and mechanical agent, is pres> APARTMENT OF AGRICULTURE — GEORGIA. [360] ent in most soils in sufficient quantity to meet all demands for it in the first capacity. Phosphate rock and animal bones furnish the chief com- mercial source of phosphoric acid. Potash, next in importance to phosphoric acid, is ex- ported from Germany in the two forms of sulphate of pot- ash and chloride of potassium. From hard wood ashes it is obtained as carbonate. It is furnished also to soils, by the decomposition of igneous rocks containing felspar. In some instances the debris of these rocks is, in some localities, deposited in vast beds in connection with marl, known as green sand marl. There is a deposit of this marl in Houston, and other counties both -east and west of it, which analyzes from two to three per cent, of potash. Fawn-yard manur€> which is a complete manure in the sense of containing all of the elements of plant-food, has in all time been used in soil fertilization, and answers an admirable purpose when applied broadcast in large quanti- ties ; but the supply is too limited, especially in a planting region, to accomplish the purpose on a large scale. The chief reliance for soil improvement on a large scale must ever be the growth of leguminous plants, to be re- turned to the soil, in connection with the application of the principal mineral elements in conjunction with a judicious rotation of crops, which require the mineral elements in different proportions. The plants used in this country for this purpose are clover, the field pea or bean, and common vetch. Dr. St. Julien Ravenel, of Charleston, South Carolina, has been conducting some very interesting experiments on the coast lands of his State, in which he applies what he calls the ash element, composed of 500 pounds of cal- cined marl, and 1,000 pounds of ground phosphate rock and 500 of kainft, to peas on cultivated lands, and to vetch on meadows, at the rate of 400 or 500 pounds per acre. [361] SCIENTIFIC MANUAL. 75 The growth of the peas and vetch is materially increased on the coast lands of South Carolina, by the application of the so-called ash element, and the vines being either plowed into the soil, or left to decay on its surface, restore whatever of plant-food they have derived from either arti- ficial or natural sources to the soil in available forms to be used by succeeding vegetation. The following extract from the report of a special com- mittee of the Agricultural Society of South Carolina, shows some of the effects of this system on the coast lands of that State, the only artificial application being 500 pounds of the so-called ash element. Extract from Beport of Committee of South Carolina Agricultral Society, made March 22, 1878. " The report of Mr. Albert M. Rhett, of the Atlantic Phosphate Works, to this Society, in November last, on experiments with these fertilizers under the direction of Dr. St. Julien Ravenel, is relied upon for this fact. Mr. Rhett told us in his paper of 45 bushels of Indian corn, of 50 bushels of oats on land previously so poor that, with- out manure, it would not make above five of corn and eight of oats; of wheat grown at the rate of 40 bushels per acre, and of 9,000 pounds of hay to the acre produced through these vetches and this ash element." The hay was made from Bermuda grass. The mineral matters are fed to the legumes, peas and vetch, which decay and supply these and the nitrogen they contain, to the succeeding crop. The results of this sys- tem, so far, have been very remarkable on the coast lands of South Carolina, and give promise of important influen- ces upon the agriculture of the coast regions of the Caroli- nas' and Georgia. chemical agents. Lime is the principal chemical agent which is artificially applied to soils. 76 DEPARTMENT OF AGRICULTURE — GEORGIA. [362] Its chemical action in the soil is varied and important. Its first, and most important, effect is in neutralizing acids in the soil, by forming chemical combinations with them, and in this way is said to sweeten the soil. This effect is particularly noticeable when it is applied to soils containing injurious acids, resulting from the decom- position of vegetable matter in the presence of an excess of water. With some of these acids it unites, forming in- soluble compounds, but with most of them, soluble com pounds are formed, from which plants derive important nutritive constituents. A deficiency of lime is indicated by the presence of cer- tain acid plants, such as the sorrels, for instance, which contain oxalic acid, which is poisonous to the most of our cultivated plants. Lime combines with this acid, forming oxalate of lime, a compound which is insoluble in water, but exists in a dissolved condition in the cells of growing plants. The prevalence of the sorrel in the southern part of Georgia plainly indicates the absence of lime in those soils in sufficient quantity to neutralize the poisonous effects of the oxalic, and other injurious acids which they contain, and that its application would prove beneficial. Lime also decomposes mineral compounds, preventing the injurious effects of some, while it liberates others, and places them at the disposal of the plants. The decomposition of organic matter is hastened by the presence of lime in the soil, and compounds important to vegetation are formed with the result of such decomposi- tion. Vegetable acids thus formed are neutralized by the lime, and nitrogen contained in the organic matter is rap- idly liberated and converted into ammonia, nitrate of lime, or nitric acid — forms from which plants appropriate this necessary element. Since lime is dissolved by water charged with carbonic acid, the presence of decomposing vegetable matter, one [363] SCIENTIFIC MANUAL. 77 of the results of which is the evolution of this gas, facili- tates the decomposition of the lime, renders it soluble, and hence increases its distribution in the soil. Caustic lime, however, is freely soluble in water, and is not only readily distributed through the soil, but rapidly carried down beyond the reach of vegetation. Since quick-lime is soon converted into the carbonate in the soil, its chemical effect differs but little from that of chalk or marl, but, being more finely divided, is more act- ive and available. Lime, besides acting directly as plant-food, and chemic- ally in the preparation of other substances, exerts also an important influence as a mechanical agent. Sulphuric acid, carbonic acid, ammonia, and potash, also act both as direct plant food, and as chemical agents. The interest of farmers demands the most economical means for both plant and soil fertilization, which should, as far as practicable, be coxbined. For this purpose, the pea-vine and lime in some form, together with compost of cotton seed, animal manures and superphosphate, furnish at present the most promising sources for the farmers of Georgia. Marl is locally accessible in a large portion of Southern Georgia, and quick-lime in all of Northwest Georgia, and, indeed, may be readily transported to almost any part of the State at reasonable rates, as soon as it is used in sufficient quantity to justify its being quarried and burned on a large scale. COMPOSTS. Georgia produces annually about 17,500,000 bushels, or 525,000,000 pounds ot cotton seed. About 2,0u0,000 bushels are required for planting the crop, leaving 15,500,- 000 bushels-~232,500 tons of seed to be used for manurial purposes. If the whole of this was composted with ani- mal manure and superphosphate, according to the formulae published in the circulars of this Department, there would be produced 620,000 tons of compost ; enough to manure, 78 DEPARTMENT OF AGRICULTURE—GEORGIA. [364] at the rate of 300 pounds per acre, 4,133,333 acres, or at the rate of 500 pounds per acre, 2,480,000 acres. The area planted in corn, wheat, oats, rye, barley, rice, cotton, tobacco, sugar cane, sorghum, sweet potatoes, Irish potatoes, ground peas, and vineyards, in Georgia, according to the returns of the tax receivers, in 1875, was 4,494,724 acres. By carefully husbanding home manures of every kind, and composting them with superphosphate, containing a small per cent, of potash, derived from kainit, or chloride of potassium, enough manure may be composted on Geor- gia farms, by a comparatively small outlay for potash and phosphoric acid, to manure on the plan of plant fertiliza- tion, nearly the whole cultivated crops of the State. This, if used in conjunction with pea vines turned under in the fall, and lime and marl spread broadcast over the land for soil fertilization, would very rapidly renovate the worn lands of the State. For formulae for composting, see Appendix. Mechanical Agents. Lime, marl and vegetable matter are the principal me- chanical agents, and should invariably be used together, since each materially increases the efficacy of the other. Lime acts mechanically upon stiff soils by loosening them, rendering them more friable, and hence facilitates the penetration of the roots of plants. It also stiffens light soils by pulverizing the coarse particles, and thus ren- dering them more compact. Vegetable matter turned into the soils, either green or dry, has the following effects when reduced to the condi- tion of humus 1. Humus renders stiff soils friable and open. 2. It absorbs moisture from the atmosphere, and thus supplies plants with it. 3. It retains the moisture longer than any other ingre- dient of soils. [365] SCIENTIFIC MANUAL. 79 4. It furnishes a considerable portion of carbon to plants either directly or indirectly. 5. In its widest sense, it supplies the mineral elements of decayed matter in soluble forms for plant-food. 6. It absorbs and*holds free ammonia and its carbonate, and thus supplies plants. 7. It absorbs lime and its carbonate, and renders it as- similable as plant-food. 8. It furnishes a solvent to the soil (carbonic acid), for the silicate of potash and phosphate of lime, by which plants are supplied with the two important compounds, phosphoric acid and potash. 9. In warm climates, it cools the soil by the alternate imbibition and evaporation of moisture. 10. It is, in fact, a prime agent in the laboratory of na- ture, for carrying on chemical changes in soils, producing heat, evolving carbon, oxygen, and hydrogen, as well as nitrogen, obtained by absorption. — [Scientific Agricul- ture. — Pendleton.] One of the causes of the remarkable effects of composts upon the denuded soils of Georgia, may be attributed to the humus which they contain. A zvord of caution in relation to the use of lime, may pre- vent disastrous results to the inexperienced. Lime should not be applied to soils deficient in vegetable matter, without a simultaneous application of either coarse manure or vege- table matter of some kind. It should not, however, be mixed with animal manures, or any other containing any considerable percentage of ni- trogen, before it is spread upon the soil. It converts ni- trogen into ammonia, which is volatile, and will pass off as a gas into the atmosphere. This action of liberating ammonia is beneficial if it takes effect in the soil, where it is immediately absorbed and re- tained, by humus or clay, for the use of plants. These cautions apply only to quick-lime, or the carbon- 80 DEPARTMENT OF AGRICULTURE— GEORGIA. [366] ate ; sulphate of lime has the opposite effect of fixing the ammonia in an available form — the sulphate — and hence its incorporation with animal manures is very desirable. From forty to fifty per cent, of pure, high-grade super- phosphate is sulphate of lime, or gypsum, and hence the application of gypsum to composts, in which superphos- phate is used, is not necessary. The beneficial effect of sulphate of lime, when applied as a top-dressing to plants, especially to legumes, is at- tributed to its power of fixing ammonia from the air. THE ATMOSPHERE IN ITS RELATIONS TO VEGETATION. There is a mutual relation between the atmosphere, plants, and animals, which beautifully illustrates the econi- omy of nature. The atmosphere is a mechanical mixture of oxygen and nitrogen, with small quantities of carbonic acid, ammonia, and watery vapor. Its composition is nearly invariable at all points on the surface of the earth, its uniformity being preserved by winds and currents. Though the per cent, of carbonic acid in the atmosphere is extremely small, plants derive all of their carbon from it, through the medium of their leaves and other green parts. "Every six pounds of carbon in existing plants have withdrawn twenty-two pounds of carbonic acid gas from the atmosphere, and replaced it with sixteen pounds of oxygen gas, occupying the same bulk." — Gray. The carbo-hydrates, or heat and fat producing constitu- ents of plants, sometimes called the ternary compounds, from the fact that they are composed of three elements — carbon, hydrogen, and oxygen — are derived principally from the atmosphere ; though the hydrogen is probably absorbed entirely by the roots, in water, and oxygen in part from the same source. [367] SCIENTIFIC MANUAL. 81 While the composition of the atmosphere cannot be changed by man, it is supposed that the application of sulphate of lime (gypsum) to the surface of plants facili- tates the absorption of a portion of its nitrogen as am- monia. Rain, also, especially when accompanied by electricity, carries down to the soil, for the use of plants, ammonia from the atmosphere. In periods of drouth, the evaporation of moisture from the surface of the leaves of plants is often in excess of its absorption by their roots, and wilting of the leaves and general contraction of the plant results. The plants re- sume their normal condition during the night, by the res- toration of the equilibrium between the evaporation from the leaves, and the absorption of moisture by the roots. Unlike the soil, the atmosphere cannot be exhausted either of its constituents necessary in plant nutrition, or of the oxygen essential to animal respiration. When we consider the vast amount of carbon in the ve- getation which covers our globe, and that the whole of it has been derived from the atmosphere, the question natur- ally arises, " How is this carbon restored to the air ?" The carbon in all vegetation is derived from the atmos- phere in the form of carbonic acid. This is a product of the decay and combustion of vege- tation and animal matters, the combustion of coal and oils, and of the respiration of animals. Each decaying leaf, each flickering taper, each respira- tion of an animal, however small, yields up its contribu- tion of carbonic acid to the atmosphere. Plants absorb carbonic acid during the day, through their leaves and other green parts, assimilate the carbon, and give off the oxygen to the air, while a small quantity of carbonic acid is given off during the night. Animals retain the oxygen, and exhale carbonic acid at all times, 82 DEPARTMENT OF AGRICULTURE — GEORGIA. [368] thus illustrating the beautiful harmony and economy of natural laws. Carbonic acid is essential to the life and growth of plants, oxygen to the respiration and life of animals. They re- ciprocally supply each other's wants. Plant life is, how- ever, independent of animal, since all of the carbonic acid contained in vegetation consumed by animals, would, in the natural process of decay, be returned to the air with- out the intervention of animals, which only expedite its return ; but animal existence is absolutely dependent upon vegetation. Animals consume, either directly or indirectly, only what plants produce. They produce but little directly from the mineral world. Graminivorous animals feed upon vegetation only, to supply food for carnivora, so that [it is almost literally true that "all flesh is grass." There is another reciprocal relation between the atmos- phere and vegetation, which is of great practical import- ance, and which man may to some extent control. This is found in the mutual influence of vegetation and the moisture of the atmosphere upon each other. Plants, by evaporation from their leaves, restore a vast amount of moisture to the atmosphere, and thus materi- ally meliorate its condition. "A recent experimant made by Knop, showed that a dwarf bean exhalted, in 23 days in September and Octo- ber, 13 times its weight of water. He further established the fact, that a grass plant will exhale its own weight of water in 24 hours in the hot, dry days of summer; and that a maize plant exhaled 36 times its own weight of water from May 2d, to September 4th." — [Scientific Agricul- ture. — Pendleton. ] From these facts, some idea may be formed of the vast amount of moisture which .is exhaled in the aggregate, by the whole vegetation of the globe. It demonstrates also [369] SCIENTIFIC MANUAL. 83 the folly of a wholesale destruction of forests. It is a well known fact that the destruction of forests causes the grad- ual drying of the climate. CHAPTER VI. Soils in their Relation to Vegetation. Soils naturally depend for their mineral elements upon the source from which they are themselves derived, but their fertility often depends more upon artificial treatment than original source. All soils owe their origin primarily to rocks, and are ameliorated by vegetation, the larger part of the latter having been derived from the atmosphere. Soils, as regards their origin, are classed as sedentary and transported. Sedentary soils are those which overlie the rocks from which they have been formed. A very correct idea of their original mineral constituents may be obtained from those of the underlying rocks, allowing of course for modi- fications resulting from the process of decomposition, and subsequent treatment. Such soils are found in Middle and North Georgia. Transported soils are such as have been drifted from the locality of the parent rocks, and deposited by the agency of glaciers or floods, in regions less elevated than those in which they originated. Transported soils are subdivided into dtift, alluvial and colluvial, according to the circumstances of their deposi- tion. Drift, is found on the border of the primary and tertiary formations of this State, extending from Augusta across to Columbus, and may be distinguished by the pres- ence of rounded, water-worn pebbles and boulders, im- bedded in the soil. 84 DEPARTMENT OF AGRICULTURE — GEORGIA. [370] It is supposed to have been deposited at the close of the Glacial Period. Alluvial soils result from the deposits of material trans- ported by running waters, which hold them in suspension until their course is sufficiently interrupted to cause the de- posit of the suspended material, as sediment. Successive deposits, continued through a long period, form stratified alluvial soils. Colluvial soils are mixtures of drift and alluvial, contain- ing both rounded and fractured rocks. Agriculturally ', soils are classified as sandy, clayey, calca- reous or marly, according to their composition. Soils con- taining a large per cent, of vegetable matter, or humus, are called vegetable moulds. Those in which sand predominates, but is united with a considerable amount of clay, are termed sandy loams ; where the proportions of sand and clay are reversed, they are termed clay loams. It is important that the farmer should understand, not only the physical character, but the chemical constituents of the soil he cultivates. There are very few soils of such physical and chemical character as to be permanently independent of the use of artificial means, either to perpetuate their fertility, or to re- store the waste from successive cropping. The physical condition of soils may be affected by a va- riety of artificial means, at the command of the landlord. Soils composed of coarse sand allow a too rapid descent of water through them ; are incapable of supplying moist- ure from below, by capillary attraction, and are deficient in the power of absorbing moisture or fertilizing gases from the atmosphere. Neither are they retentive of fertilizers applied to them. Where a clay subsoil underlies them, in reach of the plow, their mechanical defects may be some- what remedied by bringing up the clay, during winter, to [371] SCIENTIFIC MANUAL. £6 be mingled by the action of frosts and rains, with the sur- face sand. The clay fills the interstices between the grains of sand, increases its retentive and absorptive power for moisture and gases, improves its capillary action, and facilitates root action. The addition of vegetable matter in conjunction with the admixture of clay, will more effectually correct its mechanical defects. If clay is not in reach of the plow, the use of lime with vegetable matter is the most economical and effectual means to be employed to ameliorate the defective mechan- ical condition of coarse sandy soils, and thus increase their productive capacity. Clay soils are called heavy on account of the difficulty at- tending their cultivation, though their specific gravity is less than that of sandy soils, which are called light, on ac- count of the facility with which they are cultivated. The stiffness and tenacity of clay soils is remedied by an application of lime and vegetable matter, which serve as divisors, preventing the adhesion of the particles under the influence of either drouth or excessive wet. Clay soils are often injured by being plowed when too wet, especially in the spring, when drying winds, and a baking sun, cause a harshness, which continues through- out the growing season, and often, in our mild climate, lasting through several years. Though more difficult to cultivate than sandy soils, clay has a much greater capacity for absorbing and retaining moisture and fertilizing gases from the atmosphere. Clays deficient in vegetable matter, or without an ad- mixture of sand, often contract, when dry, to such an ex- tent as to break the rootlets of plants, and thus cause seri- ous injury. This does not occur in sandy soils or loams. Dry, pulverized clay may be advantageously used as an absorbent in stables, to fix fertilizing gases, and especially ammonia, which would otherwise escape into the atmos- 86 DEPARTMENT OF AGRICULTURE — GEORGIA. [372] phere, and be, to a large extent, lost. A notable illustra- tion of its absorbing power, and consequently deodorizing power, is found in its use in the commode, or "earth closet." Tainted meats may be sweetened by being buried for a time in clay soil. Color and texture of soils exert a very decided influence upon the absorption and radiation of heat, both of which depend materially upon their absorptive and retentive powers for moisture. It has been found, by experiment, that the difference between soils whitened and blackened was nearly the same as that between the same soils wet and dry. It has been further shown that the difference due to color is confined principally to the surface. Schubler sprinkled lamp-black and magnesia on the surfaces of different dry soils, and tested the temperatures which they attained. He found that the blackened soils attained a temperature of from 13° to 14° higher than the same soils whitened ; and that the range of increase varied not more than 2. 5° in the different soils. He also compared various soils in their wet and dry states, and found the increase of temperature in the dry, over the wet soils, corresponded very nearly with that due to the dark color, but that the whitened dry soil became warmer than the natural color wet, and that the blackened dry soils exceeded in temperature those of the natural color about as much as the blackened did the whitened. Soils which have stagnant water sufficiently near the surface to be reached by the roots of ordinary cultivated plants, are usually cold and unproductive. Thorough un- derdrawing of such soils not only affords relief from the stagnant water, but permits the surplus from heavy rains to pass off readily, facilitates cultivation, permits a free cir- culation of atmospheric air, pregnant with its burden of watery vapor and fertilizing gases, and elevates the tern- [373] SCIENTIFIC MANUAL. 87 perature of the soil, enabling vegetation to start forth with full vigor in early spring. It is difficult to estimate the importance of such a pul- verization of the soil as to admit of 2k free circulation of air. Every observant farmer has noticed the difference in the amount of moisture which accumulates by deposition from the atmosphere, during a single summer's night, on soil freshly stirred, and on that covered with a crust which ex- cludes the air. Some idea of the amount of moisture thus extracted from the air may be formed from the accumula- tion of dew upon vegetation. The more finely a soil is pulverized, the greater the surface presented to participate in robbing the atmosphere of its moisture, for the benefit of vegetation. Again, deep preparation and thorough pulverization of the soil enables it to store up moisture, which is yielded up to vegetation during drouth, by capil- lary attraction. Soils thus prepared absorb and retain water from heavy rains, which would run off to the streams from those poorly prepared, carrying with it a portion of the surface soil. Proper preparation, therefore, converts a destructive into a productive agent. MINERAL PLANT-FOOD IN THE SOIL. This is a question of special importance to the advanced agriculturist, since by availing himself of the light which science has thrown upon plant nutrition, he can not only ascertain what elements of plant-food his soil contains, but may supply its deficiencies in the character, quality, con- dition and ratio needed by different agricultural plants. Chemical analysis shows, approximately, the chemical composition of the soil, and quite accurately that of plants. Knowing, therefore, not only the elements of mineral food required by each plant, but the ratio in which they enter, the farmer may supply, for each crop, the min- eral elements that are found to be deficient in the soil, either naturally, or as the result of partial exhaustion, by successive cropping, washing and leaching. 88 DEPARTMENT OF AGRICULTURE — GEORGIA. [374] The principal mineral elements obtained from the ash of plants, are sulphur, phosphorus, silicon, chlorine, potassi- um, sodium, calcium, magnesium, iron and manganese. Oxygen and carbon are also found in small quantities. These, together with nitrogen and hydrogen, constitute all the important elementary substances found in agricultural vegetation. But few of these substances are utilized by plants in their elementary forms, oxygen being probably the only one. Sulphur is taken up by plants as sulphuric acid, silicon as silica, chlorine in the form of chlorides, potassium as po- tassa or potash, sodium as soda, calcium as lime, magne- sium as magnesia, iron and manganese as oxides of these metals, carbon as carbonic acid, nitrogen as ammonia and nitric acid, oxygen in its free state and in various com- binations, hydrogen in water and ammonia. This is not intended as an exhaustive enumeration of the forms in which these substances are taken up by plants, but only to show that, with the exception ol free oxygen, they are ap- propriated from their various compounds, instead of from their elements. These ash elements are essential to the full development of plants ; the total absence of any one of them being fatal to their very existence. In this sense, therefore, they are of equal importance to vegetation. In another sense, however, some have much greater im- portance to the agriculturist than others. It is unnecessa- ry to consider those elements, which are derived from the atmosphere, since its composition is practically beyond man's control. It is with the soil that the farmer must deal, and on his knowledge and skill in treating this, his success will depend. The term Agriculture, means the cultivation of the soil, but its cultivation does not embrace the full scope of the farmer's duty, though an important part of it. He must not only acquaint himself with the physical pe culiarities of his soil, and learn to remedy its defects, but [375] SCIENTIFIC MANUAL. 89 he must ascertain, either by analysis or experiment, or by both conjointly, the chemical constituents of his soil, in or- der that he may know to what crops it is best adapted, and what elements of plant-food need to be artificially supplied. With a knowledge of the physical and chemical require- ments of the different cnltivated crops, and a familiarity with the physical character and chemical composition of the soil, the farmer may, by supplying the deficiences of the latter, fulfill the requirements of the former. Phosphoric acid and potash are the first mineral ingredi- ents exhausted from cultivated soils, and generally the only ones which need artificial application. These, with nitro- gen, form the valuable part of most commercial fertilizers. Many soils are naturally deficient in lime, and it is often leached through the surface on others, rendering its appli- cation not only desirable but necessary. Soda and mag- nesia are beneficial, as special manures, to particular plants. Plants differ materially in the kind and quantity of min- eral matter required for their production, and thus are ex- haustive of the soil in different degrees. The following analysis of tobacco, cotton fibre, cotton seed, and wheat showing the amount of different mineral matters contained in 1,000 parts of each, will illustrate this fact : i <2* > 4 < oo 1 o Ph OS o CO ! a B 03 2 a a o So 5 ■B 03 V CO d a "E o 3 o 760 240 13 65.76 4.22 8.88 1.06 25.20 1.14 88 80 3.02 864 1,30 9.36 0.62 13.04 0.18 10.80 Cotton fibre 987 0.90 Wheat 980 20 6.25 0.70 2.44 0.62 9.24 0.48 0.34 Not esti- mated. 0.61 Cotton seed 963 37 11.24 1.44 5.01 8.84 12.17 1.39 0.39 An inspection of the foregoing analyses develops im- portant facts, which the farmer may use to his advantage. 1st. They show the principal mineral elements required by each plant for the production of those parts which are removed from the soil, and which, if not already present in the soil, must be supplied by the farmer. 90 DEPARTMENT OF AGRICULTURE — GEORGIA. [376] 2nd. They show the different degrees to which these plants exhaust the mineral elements of the soil, if only the marketable products are removed. Thus, if the cotton seed and stalks are returned to the soil, only the lint being removed, and the whole tobacco plant be removed, 1,000 pounds of the latter will extract from the soil 15J times as much potash as 1,000 pounds of the former, 8 times as much soda, 22 times as much magnesia, more than 29 times as much lime, 6 times as much phosphoric acid, 15 times as much sulphuric acid, 72 times as much silica, and 12 times as much chlorine. This explains the rapid ex- haustion of lands by the removal of successive crops of tobacco, without compensative returns of manure. Com- parisons similar to the above may be made by the reader from the Tables of the Appendix. 3rd. They indicate to the farmer the elements which should be combined, both in kind and relative quantity, for the production of particular plants. The advantage of such knowledge is forcibly illustrated by the remarkable results of the experiments of Prof. Stockbridge on plant fertilization, which have already been cited. It should be remembered, however, that most soils, not absolutely barren, are store-houses of mineral substances which, under the influence of natural agencies, are con- stantly undergoing mechanical and chemical changes, which gradually convert inert substances into available, assimilable forms. In these transformations, the alkalies, carbonic and sulphuric acids, and vegetation, both dead and living, perform an active part. A soil may be rich in all the mineral elements of plant- food, but if they are not in a soluble condition, or readily rendered so, they are absolutely worthless to plants. Natural agencies, however, are constantly at work, both mechanically and chemically, upon the mineral compounds of the soil, pulverizing them, forming new compounds, or destroying those already formed. [377] SCIENTIFIC MANUAL. 91 * 'Water, charged with carbonic acid and oxygen, is con- stantly circulating up and down through the soil, acting upon the silica, lime, phosphoric acid and potash, render- ing then soluble, and supplying them directly to the feed- ers of the plants.*' "Air is indispensable to the soil, to prepare food for plants, by the chemical action of oxygen and carbonic acid." — Sc. Agr. In order to secure a free circulation of air in the soil, thorough drainage and deep tillage are necessary. "The advantages of drainage are not confined to land which is absolutely wet, but its beneficial effects will be experienced in all those soils in which water can remain stagnant, at any time, at a less depth than three or four feet beneath the surface. Like shallow tillage, want of drainage compels the roots of plants to remain near the surface of the ground, where the)'- are not only exposed to all the vicissitudes of weather, but are also compelled to seek their nourishment within very narrow limits. Drain- age, therefore, loosens and aerates the soil and subsoil, in such a. manner that the roots of plants are enabled to pen- etrate deeper, to strata which are rarely, or never, suffi- ciently affected by drouth, to allow injury to vegetation." — (Hilgard — Agl. Rept. Miss.) To sum up, the effects of drainage are : The soil is made porous and productive, by being warm- er, and by having a greater depth for the roots. The lands dry faster after a rain, and yet resist drouth better. Fertilizers act better. It prevents washing away of the soil, and, consequently, of fertilizers. It prevents miasma and malaria by carrying off stagnant water. It not only improves the mechanical condition of the soil, but facilitates chemical action, which results in the 92 DEPARTMENT OF AGRICULTURE — GEORGIA. [378] decomposition of vegetable matter, and the increased sol- ubility of mineral compounds. , It prevents the formation of acid compounds, poisonous to vegetation. It facilitates the preparation and cultivation of the soil, and largely increases its productive capacity. Subsoiling and deep plowing accomplish some of these ends, but act better in conjunction with under-draining. Each landowner, however, must determine for himself whether his soil is of such a character as to be sufficiently benefitted by drainage and subsoiling to justify such an in- vestment of time, labor, and capital. The natural drainage of many of our soils is sufficient for agricultural purposes, and no land without a compact (generally clayey) subsoil will be materially benefitted by sub-soiling. Its propriety will depend also upon the chemical composition of both soil and subsoil. This may, to some extent, be determined by chemical analysis, of which Prof. Hilgard, in the Agri- cultural Report of Mississippi, says : " Analysis teaches us what are the kinds and respective quantities of the ingredients contained in crops, soils, and manures. It teaches us, therefore, which of the latter two will be best calculated to promote the successful culture of the former ; to obtain which knowledge by mere exper i- menting, would require a disproportionate amount of time and labor. The absence of a single one of the ingredients necessary for the growth of a plant renders unavailing the presence of all the rest. Unless we are taught by analysis which ingredient or ingredients, of which there is a defi- ciency, we shall be compelled, in order to be safe, to add all of them, at great and unnecessary expense ; for it will be of no practical advantage to have added an additional supply of those of which there is no lack. "The importance of reliable analysis of crops, soils and manures is, therefore, obvious enough ; yet the mere pres- ence of any useful ingredient in a soil or manure, as de- [379] SCIENTIFIC MANUAL. 93 monstrated by analysis, does not yet assure us that it is present in an available condition, so as to be ready for ab- sorption by the plant ; for the agents which the chemist uses in his laboratory are much more powerful than those placed at the command of vegetables by nature ; thus far then, mere ultimate analysis is not a direct indication of the pro- ducing powers of the soil. "This consideration becomes of most serious moment, where the rocks from which the soils are originally derived are in close proximity, so that a large amount of unde- composed material may be supposed to be unevenly diffused throughout the soil." In South Georgia, where the soils have been brought a long distance, and have become more thoroughly inter- mingled and comminuted, an analysis of a sample, properly selected, would probably indicate very nearly the compo- sition of the soil of a large area. The analysis of crops is important in connection with that of soils and manures. " The determination of the kind and quantity of the mineral ingredients which crops withdraw from the soil is at least equally important with that of the soils them- selves. It informs us what, and how much, the soil has lost in cultivation, and thus enables us to select judiciously the most economical mode of replacing the drain ; provi- ded, of course, that the composition of the fertilizers at our command be also known to us." — Ibid. Soil exhaustion is the result of the withdrawal of the ash ingredients of the crops removed, or of denudation by sur- face washing. Complete exhaustion never occurs — the term, as used, being relative only. Complete exhaustion would imply the entire removal of the mineral elements of plant-food from the soil. This is not the sense in which the term is here used. A soil is said to be exhausted when it ceases to produce remunerative crops. This may result from the 94 DEPARMENT OF AGRICULTURE — GEORGIA. [380] removal of a single necessary mineral element, the absence of which renders unavailable the others, though present in abundance. Fortunately for man, howevei, nearly all of the mineral elements exist in practically inexhaustible supply, so that even on the most worn soil;, only a few of these elements need be artificially supplied and these are readily accessible. Phosphoric acid is, as regards the necessity of artificial supply, first in importance, potash second, and lime, per haps, third ; other elements being required in very small quantities for general vegetation. Generally phosphoric acid and potash, of the inorganic or mineral elements, and nitrogen, of the organic, are all that need be supplied by the farmer to secure remunera tive crops, even from worn soils, if a judicious system of rotation of crops, involving a liberal return of vegetable matter from legumes, to the soil, is practiced. If all the vegetation annually produced upon the land was returned to it, the soil would annually increase in fer- tility. If, however, as is usual, a part of the crop is annu- ally removed, mineral substances equivalent to those con- tained in the portion of the crops carried off must be re- turned to the land to maintain its normal fertility. The roots of all plants, and especially those of the legumes, have a power of acting chemically upon the mineral com- pounds of the soil in such manner as to render a portion of them available as plant-food. To this power, in part, is attributed the beneficial effects of the cultivation of the legumes, peas, clover, etc. The following list shows the amount of mineral ingredi- ents withdrawn from the soil by different crops. It is taken from Prof. Pendleton's " Scientific Agriculture," and is worthy of careful study by farmers : A crop of 750 pounds of seed cotton will carry off from an acre of land 23.25 pounds'of nitrogen, and 33.3 pounds [381] SCIENTIFIC MANUAL. 95 of ash, of which there will be of the most important min- eral elements: Potash 8.30 pounds. Magnesia 5.05 pounds. Sulphuric acid ....0.50 pounds. Soda 3.20 pounds. Chlorine 0.30 pounds. Phosphoric acid..7.20 pounds. Lime 0.83'pounda. A crop of 8J bushels of wheat, with an equal quantity, by weight, of straw, will carry off 11.50 pounds of nitro- gen, and of the mineral elements : Potash 2.12 pounds. Magnesia 0.74 pounds. Phosphoric acid.. 2.57 pounds. Soda 0.31 pounds. Chlorine trace* Lime 0.46 pounds. Sulph'ric acid.0.26 pounds. Total ash 35.15 pounds. A crop of Indian corn, in the ear, equal to 9 bushels of grain, will carry off from an acre of land, in pounds : nitro- gen, 9.00. Potash 2.13 Magnesia 0.76 Chlorine trace. Soda 009 Phosphoric acid 2.27 Lime 0.18 Sulphuric acid 0.09 Total ash 7.94 pounds. A crop of oats, grain and straw, allowing that the weight of the straw is double that of the grain, the crop being 12 bushels per acre, will carry off: Nitrogen 12.0 pounds. Lime 1.62 pounds. Phosphoric acid... 2.27 pounds. Magnesia 12.0 pounds. Soda 1.52 pounds. Sulphuric acid 0.59 pounds. Chlorine trace. Potash 4.72 pounds. Total ash 32.76 pounds A crop of peas, consisting of the seed, equal to 9 bush- els per acre, will carry off: nitrogen, 16.50 pounds. Min- eral substances : Soda 0.18 pounds. Sulphuric acid. 0.17 pounds. Chlorine 1.11 pounds. Phosph'ric acid. 1.81 pounds. Potash .2.02 pounds Magnesia 0.40 pounds. Lime 0.21 pounds. Total ash 14.05 pounds. By reference to these tables, the farmer can not only learn the amount of plant-food extracted from the soil by any of the crops mentioned, but has a reliable indication of the amount of those elements, which are first exhausted, that he must apply to the soil to produce a given crop. It is fair to presume that most soils will be benefitted by the application of ammonia, phosphoric acid, and potash, though some probably have a sufficient quantity of each in their virgin state. Knowing the amount of each element of plant-food re- quired for the production of a given crop, the farmer may 96 DEPARTMENT OF AGRICULTURE — GEORGIA. [382] calculate beforehand, with a moderate degree of certainty, the increase that will result from the application of a spe- cific amount of plant-food, in the proper combination, if other circumstances are favorable. To illustrate : If the natural soil will produce 12 bushels of oats per acre, with the necessary amount of straw — as- suming that the soil (as is usually the case) contains a suf- cient supply of lime, soda, magnesia, sulphuric acid, and chlorine — it may be reasonably expected that the applica- tion of 12 pounds of nitrogen, 4.72 pounds of potash, and 2.27 pounds of phosphoric acid, would produce 24 bush- els, with the necessary straw, or 12 bushels more than the natural soil ; but the results depend upon such a variety of circumstances, that many experiments will be required to establish the correctness of the assumption. Since all of the mineral food derived from the soil must pass into the plant in solution in water, each element, to be available to the plant, must be either soluble, or promptly rendered so, by natural agencies, during the pe- riod of active growth of the plant. The influence of climate must be considered in the treat- ment of soils. This is too often neglected by farmers in the South, whose agricultural literature is principally adapted to more northern climates, where most of such literature has originated. While the general principles of agricultural science are the same everywhere, their application to practice varies ac- cording to a multiplicity of circumstances, the influence of which, each individual must decide for himself, according to his surroundings. Soils in a warm climate are more rapidly exhausted under tillage than those of cold climates, for the following reasons : 1. Vegetation has a longer period of growth in warm climates, in which to extract plant-food from the soil., 2. There is a less rapid and thorough decomposition of [383] SCIENTIFIC MANUAL. 97 mineral substances by the expanding effects of frozen water, while more of such substances are annually ex- tracted from the soil. 3. The vegetable matter in the soil is more rapidly de- composed under the influence of warmth and moisture, though more needed in warm than in cold climates. 4. Fertilizing gases are liberated more freely in warm climates. This continues throughout the year, where the earth is never covered with snow. Nitrogen, especially, is rapidly removed from the soils of warm climates. Humus is of more importance, though less abundant, in the soils of warm than in those of cold climates. It serves the double purpose of absorbing and retaining mois- ture, and thereby cooling the soil, and consequently, is of great benefit independently of the plant-food, which it yields to the soil by its decomposition. Our climate necessitates different treatment of soils, both in the preparation and cultivation, from that practiced fur- ther north. Winter fallow is less beneficial where the freezes are light, root cutting is more injurious, and level culture, ex- cept on bottom land, a necessity. CHAPTER VII. FERTILIZERS. Fertilizers are classed according to their source as animal, mineral and vegetable. These are also called mechanical, if their principal influence is exerted in affecting the physi- cal condition of the soil ; and chemical, if they produce changes in the soil, or furnish plant-food directly to vege- tation. There is a distinction made also between natural and artificial fertilizers. A fertilizer proper is a substance, either simple or com- 7 98 DEPARTMENT OF AGRICULTURE — GEORGIA. | [384] pound, which, when applied to the soil, supplies available plant food in such form as to be readily absorbed by the roots of plants under natural circumstances. Fertilizing agents aid plants in appropriating plant-food already in the soil without directly supplying it — warmth and moisture are fertilizing agents. The great bulk of the food of plants is derived from the atmosphere, which is invariable in composition, and beyond the control of human agencies. It is of such fertilizing substances as may be made tribu- tary to plants through their application to the soil, the productive capacity of which is, to a large degree, under the control of the skillful agriculturist, that this chapter will treat. The principal fertilizers of animal origin are fish, excre- mentitious matters from animals and fowls, and the flesh, blood, bones, horns, hoofs and hair of animals. Fish and fish scraps, the refuse from oil factories, are used as a commercial source of ammonia, of which it con- tains over five per cent., with a moderate per cent, of phos- phoric acid. It is used for the purpose of supplying am- monia to commercial compounds. The fish, however, decomposes so promptly that its ni- trogen is, in a very short time, converted into actual am- monia, which, being all promptly available, acts injuriously in cases of drouth, and is exhausted before the period of growth of our summer crops is completed. For the cot- ton plant, which continues its growth throughout our long summers, a part should be actual, and a part potential am- monia, or nitrogen, in such a form as to be capable of being converted into ammonia. In the case of fish, the decom- position is so rapid that its entire nitrogen is promptly con- verted into actual ammonia, and hence the tendency of fertilizers, ammoniated with fish, to "fire" crops in times of drouth. Excrement varies in its composition : [385] SCIENTIFIC MANUAL. 99 1. That of no two varieties of animals is alike in chem- ical composition. 2. That from the same animal varies with the character of the food consumed. 3. That from young growing animals is less valuable, especially in phosphoric acid, than that from grown ani- mals. 4. That from fat animals is richer in nitrogen than that from those in a lean condition, where much of the food consumed is appropriated to the restoration of flesh as well as fat. 5. That from fowls is richer than that of animals, be- cause the solid and liquid excrements are combined. 6. Liquid excrement of all animals is richer in plant- food than the solid, and should, as far as practicable, be saved by farmers. Flesh, blood, horns, hoofs and hair are rich in nitrogen, and are used by manufacturers of commercial fertilizers to supply that important element to their compounds. The percentage of nitrogen contained in them ranges from six to sixteen. Dried flesh and blood are very extensively used as sources of ammonia, by manufacturers of fertili- zers. The dried flesh is derived principally from countries where animals are killed in large numbers for their hides, horns and tallow, and the flesh boiled for extract of meat. "The fibrinous residue, when dried, becomes a most ad- vantageous nitrogenous material for use in the manu- facture of ammoniated fertilizers." Dried blood is derived from the extensive slaughter- houses of the United States, and other countries, where millions of animals are slaughtered for food. The blood is either dried, or solidified by coagulation, and thus is formed a condensed mass, exceedingly rich in nitrogen. Dried ox-blood contains from fifteen to seventeen per •cent, of nitrogen. Mineral fertilizers are those substances which, derived 100 DEPARTMENT OF AGRICULTURE — GEORGIA. [386] primarily from minerals, are found in the ash of plants, when they are burned with free access to the air. The most important are potash, soda, lime, magnesia, phos- phoric acid, sulphuric acid, silica, and chlorine. Of these, phosphoric acid may be said to be always beneficial, as an artificial application to the soil, potash generally, lime often, soda, chlorine, and magnesia, for particular plants, such as tobacco, beets, etc., and the others, never. Phosphoric acid is derived principally from animal bone, phosphate rock, as found near Charleston, S. C, and in various other parts of the globe, and from the decay of animal and vegetable matters. Its principal office in plant nutrition, seems to be to increase the production of fruit, and especially seed, rather than stalk. By reference to the Tables of Analyses, in the Appendix of this work, the reader will see that it is an important constituent of the ash of the seeds of all agricultural plants. Soda is derived, principally, from the chloride of sodium, or common salt, which abounds in the waters of the ocean, in salt springs, and in vast deposits of rock salt. It is present in sufficient quantity, in most soils, for the pur- poses of vegetaiton, but may be profitably supplied, as a special fertilizer, to a few plants, such as tobacco, beets, turnips/ carrots, etc. Salt {chloride of sodium) is especially beneficial to cab- bage and asparagus, and applied to gardens, in early win- ter, is destructive of injurious insects. Nitrate of soda is found as an incrustation on the surface of the earth, in Peru. It acts finely, when applied as a top- dressing, on small grain and the grasses. Potash is used for agricultural purposes, in the various compounds of potassium, which, uniting with carbonic acid, forms carbonate of potash; with sulphuric acid, sul- phate of potash ; with chlorine, chloride of potassium, (muriate of potash); with nitric acid, nitrate of potash, ni- tre, or saltpeter, and with silicic acid, silicate of potash.. [387] SCIENTIFIC MANUAL. 101 The latter is formed naturally in soils, by the dismtegration of rocks containing feldspar or mica. The granites of Georgia yield this form by decomposition. Carbonate of potash is found in wood ashes, which fur- nishes a cheap, but limited source, of this important and necessary constituent of all fertile soils. The caustic prop- erty of lye is due to potash leached from the ashes. Leached ashes differ from unleached only in the per cent. of potash contained — both are valuable as fertilizers. Sulphate of potash is derived, principally, from kainit, which is extensively mined near Strassfurt, Prussia. Kainit contains from 23 to 25 per cent, of sulphate of potassa, from 14 to 28 per cent, of magnesia salts, and 30 to 48 per cent, of chloride of sodium. Pure sulphate of potassa contains 54 per cent, of potassa, and 46 per cent, of sul- phuric acia. Kainit is the best commercial source of pot- ash, for the reasons that the foreign matters associated with it are, to some extent, valuable as an application to the soil, the sulphuric acid acting as a chemical agent for the reduction of other substances in the soil, the magnesia salts and chloride of sodium serving as plant- food, and the al- kalies being presented in such combinations as not to vola- tilize ammonia from nitrogenous substances, with which the farmer or manufacturer may desire to compound it. Chloride of potassium is another important source of pot- ash. It is derived mainly from the mines near Strassfurt, Prussia, where it is found in a vast bed of clay, overlying one of rock salt. When pure, it contains 52.35 per cent, of potassium and 47.65 of chlorine. Nitrate of potash, commercially known as nitre or salt- peter, is procured from certain districts in India, and from caves, by simply leaching the earth with water, and evapo- rating the solution thus obtained. It is also made from artificial nitre beds, in many parts of Europe. Lime exists in nature in vast quantities. 1st. As carbonate of lime, which is composed of lime DEPARTMENT OF AGRICULTURE— GEORGIA. [388] and carbonic acid. It is found abundantly in nature in the shells of marine animals, in coral, chalk, marble and lime- stone. These shells and rocks, "when strongly heated, es- pecially in a current of air, part with their carbonic acid, and quick-lime remains behind." Carbonate of lime is found in considerable quantity in the ashes of most plants, and especially in those of trees. Quick-lime, or caustic lime, when taken from the kiln, is a hard, dry substance which, when exposed to the air, slowly absorbs moisture, becomes air-slaked, and crumbles to a fine powder, in which form it is readily applied to, and easily mingled with, the soil. Quick-lime is a compound of calcium and oxygen. Air-slaked lime is extensively applied to cultivated lands in Europe, and portions of the United States. It acts bene- ficially upon stiff, clay soils, by rendering them open, and hence more readily penetrable by rain, air and the roots of plants. It facilitates decomposition of vegetable mat- ter and coarse manures, and, by chemical action upon in- soluble minerals in the soil, renders them available as food for plants. It also, to some extent, furnishes food di- rectly to the roots of plants. By its action upon vegeta- ble matter, in breaking down its organic structure, it not only liberates the mineral substances which the organic matter contains, but converts the potential into actual am- monia. It should not be applied to soils denuded of vegetable matter. An important effect of lime in soils is found in the neutralization, by its alkaline property, of injurious vegetable acids. Since lime has a tendency to sink into the soil, it should be applied to the surface. The quantity to be applied, and the frequency of the application, will depend upon the character of the soil and its previous treatment. In some countries large quantities are applied at long inter- [389] SCIENTIFIC MANUAL. 103 vals, while in others smaller applications are made, at shorter intervals. In portions of England, as much as 250 to 300 bushels of slaked lime are sometimes applied per acre, followed by applications of from 8 to 20 bushels every four or six years, according to circumstances. Larger applications may be made to stiff clays than to sandy soils, and in either case the quantity should depend somewhat upon the depth of the soil, and the amount of vegetable matter it contains. Again, since vegetable matter decomposes more rapidly in warm than in cold climates, larger applica- tions are generally admissible to soils in the latter than in the former. Lime should be invariably applied broadcast, and thor- oughly incorporated with the soil, if applied without pre- viously composting with vegetable matter. Lime should never be composted with animal manures, or other substances containing a considerable percentage of nitrogen. If composted with such material, the loss of ammonia will result. To secure the full benefit of liming, the soil, if not natur- ally so, should be first thoroughly under-drained. If marls are used, the quantity applied per acre should depend upon the per cent, of carbonate of lime they con- tain, and upon the physical character of the marl used, as regards its pulverulent condition or the facility with which it crumbles before or soon after its application to the soil. The necessity of an application of lime to any particular soil, may be determined to some extent, by the character of the spontaneous growth, but more accurately by experi- ment on a small and comparatively inexpensive scale. Another, and very important form in which lime occurs in nature, is in combination with sulphuric acid, known to the chemist as sulphate of lime, and to commerce as gyp- sum, ground plaster and land plaster. 104 DEPARTMENT OF AGRICULTURE — GEORGIA. [390] It contains lime 32.56 per cent. Sulphuric acid.. ...46.51 " " Water 20.93 " " 100.00 " " It is found in extensive beds in different parts of the world, and after being ground to a powder, is much used in old agricultural States as a top dressing for small grain and pastures. It constitutes from 40 to 50 per cent, of every commercial superphosphate, in which it occurs as a surplus ingredient, resulting from the treatment of the phosphate of lime with sulphuric acid, and costs the consumer nothing. If, therefore, superphosphates are used, there is little ne- cessity for applying gypsum. Its beneficial effects have been attributed by some to the sulphur of the sulphuric acid, by others, to the action of the sulphuric acid in fixing ammonia from the atmosphere, and by others still, to the lime, while each probably con- tributes somewhat to the benefit derived from its use. Its action on plants, especially on the legumes, is often very remarkable, but the particular manner in which it acts is not well understood. Magnesia is beneficial to some plants and may be defi- cient in some soils, but is generally present in sufficient quantity to supply the needs of our cultivated plants. Since kainit is generally employed as a source of potash in commercial fertilizers, a sufficient amount of magnesia is usually incidentally supplied. Vegetable fertilizers vary in value with the character of the plants used. They constitute the main reliance for the restoration of exhausted lands, and, indeed, may be regarded as an indis- pensable factor in this process. They not only restore to the soil, in readily available forms, the mineral elements and nitrogen derived from the [391] SCIENTIFIC MANUAL. 105 soil, but return, also, vast quantities of those substances taken from the atmosphere to ameliorate the mechanical condition of the soil, and serve as absorbents of moisture and fertilizing gases from the air. A certain class of plants, known as legumes, embracing the clovers, lucern, peas, beans, and other pod-bearing plants, are especially beneficial as soil fertilizers. Their long tap-roots penetrate deep into the subsoil, from which they assimilate mineral food, which, after being used in building up the leaves and stems of the plants, is deposited, at their death, on the surface soil, to be used by future crops. Besides this power of deep penetration, this class of plants has greater capacity for decomposing and appropriating mineral matter and nitrogen from the soi* than other plants, and are supposed to have a peculiar pow- er of absorbing ammonia from the atmosphere. By refer- ence to the tables of analyses of plants, in the appendix of this work, it will be seen that the legumes are especially rich in nitrogen and the important mineral elements, pot- ash, phosphoric acid, lime, etc. The large quantity of nitrogen which they contain, facilitates their decay, and thus hastens the restoration of their mineral elements to the soil. The peculiar benefits derived from decayed vegetable matter, have already been given in detail in this work. By the application of mineral fertilizers to the legumi- nous plants, their growth is largely increased, and thus their fertilizing capacity improved. It is a fact well known to practical farmers, that even when the crop of clover or pea vines is removed from the land, its producing capacity for the grasses or cereals is materially increased. The improvement is still greater when the crop is turned under, or allowed to decay upon the land. Where there are beds of muck, rich in vegetable matter, it may be banked, in position, during dry spells in summer, 106 DEPARTMENT OF AGRICULTURE GEORGIA. [392] mixed with lime, and allowed to remain until convenient to haul out ; but if it has to be hauled more than a few hun- dred yards, the cost will amount to prohibition. Pea vines and lime furnish not only the cheapest, but the best means, at the command of Georgia farmers as a basis for the res- toration of their worn lands. Cotton seed, a waste product peculiar to Southern agricul- ture, afford a most valuable vegetable fertilizer. Georgia produces annually 262,500 tons, and the cotton States 2,- 362,500 tons of these seed. Commercial fertilizers , so extensively used, of late, in Geor- gia, supply the immediate demand for plant fertilizers but furnishing, as they do, principally mineral plant-food in concentrated form, apart from their immediate influence on plant nutrition, they act only chemically upon the soil, which is unable to respond profitably to their application if denuded of vegetable matter. The improvement in the preparation and quality of the compounds offered to the farmers of Georgia, within the last five years, has been very marked, while their cost has been considerably reduced. Under the operation of the present inspection laws, as administered, none but reliable compounds can be offered on the Georgia market, and farmers are enabled by the published analyses, largely distributed, to inform them- selves as to the chemical composition of every brand ad- mitted to sale in the State. The principal elements of plant-food in the commercial fertilizers on our market are nitrogen, phosphoric acid and potash. The manufacturers of commercial fertilizers have practically adopted the conclusions of scientific experi- menters, that these three elements are generally the only ones necessary in artificial fertilizers. Many, however, misled by the results of experiments conducted on soils in Georgia derived from granite, have omitted potash in the preparation of their compounds, [393] SCIENTIFIC MANUAL. 107 though intended as "complete fertilizers." Others, in re- sponse to a demand for superphosphate for composting with stable manure and cotton seed, have omitted both pot- ash and ammonia, assuming that these latter substances would be sufficiently supplied by material already on the farm. Much depends upon the source from which manufac- turers derive the "three elements" of their compounds, as well as upon the forms in which they exist when offered for sale. The price of nitrogen is estimated, according to its source, at from 25 cents down to 15 cents per pound, phosphoric acid from 12.5 to 3,5 cents, and potash from 9 to 6 cents per pound. Nitrogen is the most costly element which enters into the so-called complete manures. The expense of purchasing this, may, to a large extent, be avoided if all of the home manurial resources are hus- banded. By a liberal use of pea-vines as a soil fertilizer, and by supplementing the cotton seed and animal manures of the farm with superphosphate containing a small per cent, of potash, lands may be either improved in fertility, or their normal condition maintained with but little expenditure for nitrogen. The principal products removed from the farm in Geor- gia, and sent to market, carry off very little plant-food. If, therefore, all refuse products are either returned di- rectly to the soil, or fed to animals whose manure, solid and liquid, is applied to the soil, it will require many years, if surface washing is prevented, to become exhausted, even if no artificial fertilizers are used. The true system to be pursued by Georgia farmers is to turn under a crop of pea- vines (or allow them to decay upon the ground) every three or four years; compost with superphosphate, having a small per cent, of potash, all the animal manures and surplus cot- 108 DEPARTMENT OF AGRICULTURE — GEORGIA. [394] ton seed of the farm, using these as far as they will go, and supplying the deficiency by the purchase of ammoniated superphosphate. As the pea vine is the cheapest and best means of soil fertilization, so the compost of home manures with super- phosphate, is the cheapest and best plant fertilizer for our climate and soil. The decomposition of vegetable matter is more rapid in warm than cold climates, and the system of cultivation more destructive of humus. It is, therefore, especially important that due attention be given to supply- ing this important agent, either in green manures, or in combination with mineral manures of commerce as com- post. The full benefit of commercial fertilizers cannot be rea- sonably expected in our climate, on soils deficient in hu- mus. Our farmers have been led into much error, both in cul- tivation and fertilization by following the teachings of ex- periments, conducted under circumstances, both of climate, soil, and agricultural practice and products, widely differ- ent from those by which we are surrounded. CHAPTER VIII. PLANTS AND THEIR PRODUCTS AS FOOD FOR ANIMALS. The oroducts of the farm may be arranged in four classes; 1. The direct vegetable products, such as the cereals, hay, textiles, roots, etc., which are sold, or used on the farm, in their primitive form. 2. Secondary vegetable products, such as syrups, sugar, ■etc., which require manufacture before marketing. 3. Such as are the result of a kind of natural manufac- ture, by which the direct products of the soil are converted into beef, mutton, pork, or wool. 4. Tertiary products, which are a result of artificial con- [395] SCIENTIFIC MANUAL. 109> version of the secondary products of the natural manufac- ture of the third class, such as butter, cheese, etc. ''Man, and all domestic animals, may be supported, may even be fattened, upon vegetable food alone. Vegetables, therefore, must contain all the substances which are neces- sary to build up the several parts of animal bodies, and to supply the waste attendant upon the performance of the necessary functions of animal life." — Elements of Ag'l Ch. and Geol'y. — Johnston. Indeed the composition of animal substances may be in- ferred from that of mixed vegetation, since animals that live upon such food, must build up their frames entire- ly from that source, by simple digestion and assimila- tion. Vegetation must not only supply the carbon of the fat, the fibrin of the muscles, the saline matters of the blood, and the gelatine of the skin, hair, horns, hoofs, and bones, but must furnish the earthy matters of the bones of animals. "It is a wise, and beautiful provision of nature, there- fore, that plants are so organized as to refuse to grow in a soil from which they cannot obtain an adequate supply of soluble inorganic food— since that saline matter, which ministers first to their own wants, is afterwards surren- dered by them to the animals they are destined to feed. "Thus the dead earth and the living animal are but parts of the same system — links in the same endless chain of natural existences. The plant is the connecting bond by which they are tied together on the one hand — the decay- ing animal matter, which returns to the soil, connects them on the other."— Ag'l Ch. and Geol'y— Johnston. There are two classes of substances in plants known to chemists as albuminoids and carbo-hydrates, the former em- bracing the flesh-forming principles of the food of ani- mals ; the latter the fat and heat producing principles. The ratio of these substances should vary according to 110 DEPARTMENT OF AGRICULTURE — GEORGIA. [396] the kind of animal to be fed, and the object had in view in feeding. Table showing the proximate composition of Agricultural Plants and Products, giving the average quantities of Al- buminoids and Carbo-hydrates in 100 pounds, with their ratio to each other, compiled from tables in How Crops Grow : SUBSTANCES. Albumi- noids. Cai bo- hydrates. Ratio of Albuminoids to Carbo-hydrates as Wheat 13.0 10.0 67.6 1 to 5.2 68.0 ,... 1 to 6.8 Oats 12.0 60.9 ... 1 to 5.0 Rice.. . 7.5 76.5 1 to 10.2 Rye 11.0 69.2 1 to 6.3 Millet .. . 14.5 62.1 1 to 4.3 Peas* 22.4 25.5 2.0 1.5 2.0 52.3 1 to 2 3 45.5 ... 1 to 1.8 30.2 ... 1 to 15.0 Rye Straw 27 0 ... 1 to 18.0 29.8 1 to 15.0 Oat Straw .... 2.5 38 2 1 to 15 0 6 5 35.2 1 to 5.4 10.2 33.5 1 to 3.3 Corn Stalks 3.0 39.0 1 to 13.0 Pea Hulls 8.1 36.6 ... 1 to 4.5 Potato (Irish) 2.0 1.1 21.0 9.1 1 to 10.0 ,... 1 to 8.3 1.6 9.3 .... 1 to 5.8 Turnips (white) 8 14.0 5.9 .. 1 to 7.4 50.0 1 to 3.5 "Wheat Flour 11.8 4.5 74.1 ... 1 to 6.2 Wheat Chaff 33.2 1 to 7.4 28.3 14.4 13.4 14.2 41.8 1 to 1.4 HAY. 22.5 1 to 1.5 29.9 1 to 2.2 35.3 1 to 2.4 11.6 11.1 40.7 1 to 3.5 35.3 ... 1 to 3 39.1 48.8 ... 1 to 4.4 9.7 1 to 5 Average of all the Grasses, in bloa'm GREEN FODDER. 41.7 ... 1 to 4.3 12.9 1 to 4.3 2.5 15.0 1 to 6 « 3.7 4.5 7.7 1 to 2.3 8.6 1 to 2,3 8.0 1 to 2.3 7.8 . . 1 to 1.7 3.1 7.0 1 to 1,5 7.6 ... 1 to 2.4 8.8 1 to 3.8 Eye 3.3 14.9 ... 1 to 4.5 *| Average of two anal- Corn Forage > ysesof corn cut at dif- J ferent stages, Peas, in blossom 1.0 9.8 1 to 9.8 3.2 Z\'..'.'."" 8.2 1 to 2.6 *Peas here refer to peas proper, and not to our so-called field pea, which is really bean. The analysis of beans represents approximately that of our "cow pea." [397] SCIENTIFIC MANUAL. Ill From the albuminoids of their food, animals derive the flesh and muscle of their bodies ; from the carbo-hydrates, they derive heat and fat ; from the mineral elements of their food, the saline matters of the blood, and the phos- phate of lime of their bones are derived. As in plants, a suitable combination of all these ele- ments which contribute to animal nutrition, is necessary to produce a normal development. The ratio in which the constituents of food must exist, depends upon climate, the age and condition of the animals fed, and the purposes for which they are fed. Nature supplies, in character and variety, the food best suited for man and beasts, in the different zones of the earth. In the frigid zone, an excess of carbon is needed to supply the loss of animal heat consequent upon very low temperature. This is supplied to man in the oils and fat of the lower animals in that region, which ' accumulate vast quantities of these substances in their bodies. The circumstances of climate demand a liberal consumption of carbo-hydrates to supply the rapid combustion necessary to the preservation of animal heat ; and forbid the ex- ertion which, in more temperate climates, causes a waste of muscular tissue. In the torrid zone, on the contrary, the minimum quan- tity of the carbo-hydrates is required, since but little car- bon is needed to keep up the normal animal heat, while only a small consumption of albuminoids is necessary to supply the waste of muscular tissue incident to the climate. Instead of oils and fats, the denizens of the torrid zone subsist largely upon cooling food, such as fruits and vege- tables, which abound in profusion throughout the year. In temperate zones, where we find the greatest physical and mental activity, nature also supplies food in the neces- sary variety, and of the proper kind to meet the wants of both man and beast. Here we*find the vegetable products of the most solid and nutritious character, having an equi- 112 DEPARTMENT OF AGRICULTURE — GEORGIA. [398] table combination of 'flesh-forming, fat-producing, and blood and bone-supplying constituents, such as the cereals, grasses and legumes, by [a judicious combination of which food adapted to all animals, of whatever age and condi tion, can be secured. Again, animals require food containing a larger propor- tion of carbo-hydrates injwinter than in summer. By ex- amining the foregoing tables, it will be seen that hay and the grains, which are consumed in winter, contain a higher per cent, of the carbo-hydrates than the green food which is consumed during summer. After elaborate experiments in feeding domestic animals, conducted in Germany, if' was decided that the best ratio for general purposes, between the albuminoids and carbo- hydrates is as 1 to 3. While this ratio exists in only a few single substances, it may be secured by a proper mixture of substances hav- ing these proximate principles in different ratios. The practice of many of our farmers who feed corn and fod- der throughout the year, regardless of the temperature, is unwise. Corn probably has no superior as winter food for stock, but is too heating for an exclusive summer diet. Oats make a better summer food than corn, since its flesh-forming principles bear a larger proportion to its fat and heat-producing principles 'than they do in corn. The green grasses, however, furnish the natural food for ani- mals in summer. Mixed grasses supply the albuminoids and carbo-hydrates in better ratio than single ones, espe- cially when the legumes are mixed with the grasses. Animals, unconfined, never feed upon a single article, but upon the mixed herbage, which, varying in the^propor- tions of fat and flesh-forming princples, furnish them the means of supplying all their wants. An animal turned into a field in which clover, peas, and corn are growing, will not confine itself to either, but partake of all. Man does not confine his diet to farinacious nor carbona- [399] SCIENTIFIC MANUAL. 113 cious substances, such as fine bread, potatoes, sugar, fats, etc., but mingles with them lean meats and vegetables, to secure a proper combination of fat and flesh producers. The athlete, while preparing for feats of strength and activity, subsists mainly upon food rich in albuminoids, in order to develop, as much as possible, muscu- lar tissue. The judicious stock-breeder will acquaint him- self with the composition of the different kinds of food at his command, and select such as, either alone or by com- bination with others, will supply his animals with such food constituents as will produce the desired results. The food will vary with the objects in view. If the ob- ject of the breeder is to produce fat, then the food should contain carbo-hydrates in large proportions. If very poor animals, in which the muscular tissue has been wasted, are to be fed, the ratio between the albuminoids and carbo-hy- drates should be as 1 to 3, until a normal condition of flesh is restored, when the ratio of carbo-hydrates may be in- creased. If the production of milk is the object, the nor- mal ratio of 1 to 3, or, perhaps, 1 to 4, in winter, will give satisfactory results. If young growing animals are fed, the normal ratio of 1 to 3, with a liberal per centage of phosphate, for the production of bone, will be desirable. Animals derive all of their food, either directly or indi- rectly, from vegetation. Vegetation is supported from the soil and the atmos- phere. All the albuminoids, and most of the carbo-hy- drates, came originally from the atmosphere, but are sup- ported largely through the medium of the soil. Animals consume plants, and are in turn consumed by them. Plants derive their albuminoid compounds from decayed animal or vegetable matter. Plants take carbon from the air, and return oxygen to it. Animals take oxygen and return carbon. So plants and animals bear a reciprocal re- lation to each other. 9 114 DEPARTMENT OF AGRICULTURE — GEORGIA. [400] CHAPTER IX. AGRICULTURAL EXPERIMENTS. In discussing this subject, the first question to be con- sidered is, what is an agricultural experiment ? All of the operations of nature, whether in the vegeta- ble, animal or mineral kingdoms, are controlled by fixed laws, usually called natural laws, or the laws of nature. The object of science is to ascertain what these laws are, and their relations to each other, or, in other words, to learn from nature, by the interpretation of these laws, the will and mode of thought of the Creator, as expressed in the physical world. Natural science, therefore, bears the same relation to the physical world, that theology does to the spir- itual. One interprets God's will, expressed in His crea- tions; the ©ther, his will as unfolded in revelation. Agricultural experiments have for their object, therefore, the interpretation of God's will in relation to plant life and plant nutrition. Definitely stated then, an agricultural experiment may be defined as a question asked nature in such form and under such surrounding circumstances, natural or artificial, as to render possible a correct interpretation of the answer from the results expressed in vegetable growth. The usual obj ct of agricultural experiments is the de termination of truth for the benefit of those practically en- gaged in agriculture. The first requisite for success is, that the experimenter shill have a clear and definite idea of the question to be asked. Without this, it is not probable that the proper precau- tions will be taken to procure the necessary surroundings to secure accurate results, such as arc susceptible of cor- rect interpretation. li the question is clearly understood, and the accom- [401] SCIENTIFIC MANUAL. 115 panying circumstances accurately observed, the most diffi- cult task still remains to be performed, viz : The correct interpretation of the answer contained in the results. Again, surrounding circumstances are often beyond the control of the experimenter, and may vary so as to render the interpretation of the results difficult: hence arises the necessity for frequent repetitions of the same experiment to establish a single truth. There arc two classes of agricultural experiments, dif- fering in the surrounding circumstances. They may be properly designated as laboratory experi- ments, and field experiments. Laboratory experiments embrace those surrounded by ar- tificial circumstances, such as those conducted in pots con- taining cither water or charred sand, to which are added various fertilizing substances, either singly or in different combinations, for the purpose of determining the require- ments of plant nutrition. These experiments, every fac- tor of which is known and under the control of the expe- rimenter, are valuable, both in a scientific and practical point of view, since their results are readily interpreted; but the most fruitful of practical results are FIELD EXPERIMENTS, which, having natural surroundings, are more valuable to the practical farmer, since they may be locally employed to ascertain the needs of particular soils and plants. Laboratory experiments are competent to determine gen- eral principles of universal application, and thus serve as a valuable guide to the conduct of field experiments. They ascertain definitely what conditions and substan- ces are^necessary for plant nutrition; they add to our knowledge of the general conditions of plant-life, and sup- ply the information necessary as a basis for the conduct of field experiments. They establish general principles; field experiments determine local and definite facts. The range of field experiment is a very wide one, and 116 DEPARTMENT OF AGRICULTURE — GEORGIA. [402] at the same time, in one sense, a very narrow one. It is wide in the range of subjects of investigation, but narrow in its application ; it is wide in the range of useful results to be achieved by accurate, earnest seekers after truth, but narrow as regards the number of such laborers. Field experiments offer a domain in which each land- owner must become his own laborer ; science proper can- not enter this domain as a laborer — she can only hold the lamp of knowledge, to guide by its light, the practical farmer in his personal investigations. Science can only furnish the chart ; the farmer must guide the helm, and must pass over the same course time and again, making close and accurate observations at every advance, to avoid breakers and decoys, before he can determine with cer- tainty the true course. The principal subjects demanding investigation, through the medium of field experiments, are 1. Experiments on worn land, with the principal ele- ments of plant food, applied singly and in different combi- nations, for the purpose of determining what substances, not supplied by the soil, are needed by our various culti- vated plants. 2. Experiments on lands in "good heart," or " condi- tion," to ascertain what fertilizers produce the best results on different- plants. 3. Experiments in rotation of crops, to secure the great- est possible benefit from the fertilizers applied, together with an improvement of the soil. 4. Experiments in soil fertilization, by means of legum- inous plants, with lime, marl, or other mineral substances. 5. Experiments with composts of home manures, muck, etc., with phosphates, potash, etc. 6. Experiments with different varieties of our agricul- tural and horticultural plants. 7. Experiments with different methods of preparation [403] SCIENTIFIC MANUAL. 117 of the soil, application of fertilizers, planting and culti- vation. 8. Experiments in improving seed by careful selection. 9. Experiments with different breeds of stock. 10. Experiments in feeding stock on various combina- tions of food. 11. Experiments in fertilizing and pruning fruit trees and vines. 12. Experiments with hedging, as a substitute for rail fences. 13. Experiments in the production of crops not yet generally cultivated. 14. Experiments in drainage and irrigation. 15. Experiments with the small industries of the farm, such as the dairy, poultry, the garden, bees etc. The great variety of soil and climate found in Georgia renders it necessary that the same experiment be conducted in various localities, and on every variety of soil. Many have fallen into the error of assuming that the re- sults of experiments, conducted under circumstances widely different from those by which they are surrounded, are ap- plicable to their localities. Lawes and Gilbert deserve the thanks of the agricultural world for their careful, accurate, interesting, instructive and long continued field experiments, and yet we would err greatly if we accepted many of the results of their research as conclusive in our widely different surroundings. Owing to the fact that the principal scientific and experi- mental investigation, and the majority of agricultural pub- lications come to us from Europe and the northern portion of our own country under circumstances of soil and climate entirely different from our own, our reading agriculturists, following their teachings without the necessary modifica- tions to adopt them to their immediate surroundings, fail to secure the anticipated results. More practical men avail themselves of the reading of their neighbors, apply the in- 118 DEPARTMENT OF AGRICULTURE — GEORGIA. [404] formation gained from them with the modifications which their experience and observation teach them are necessary under the change of circumstances, and succeed. The former class are then pronounced failures, and their want of suc- cess attributed to the fact that they leant from the bookst while the failure was not due to the fact that they read and learn from books, but from the want of the necessary obser- vation and experience to enable them to make a proper ap- plication of what they learn by reading. This has been a fruitful source of the prejudice against what is called in de- rision f* book farming." We need, and must have, before our agriculture will take the position which its importance demands, scientific ex perimental investigation at home. Our own soil must be made to respond to well-directed specific inquiry as to its needs ; our own plants must be required to tell by increased production the kind of food and the conditions necessary for their highest development ; our own stock must answer by symetrical development and carcasses laden with flesh and fat, the kinds and combinations of food necessary for their comfort and increase, and the production of the great- est profit to their owners ; the products of our own dairies must tell in rich cream and golden butter the kind of stock to keep, the most appropriate food, and the best system of management both of the cows and the dairy products. By whom are these experiments to be conducted ? Will farmers undertake them ? They should be conducted both by the State and by individual farmers. The State should have stations in its principal sections, the number to be de- termined by general differences of soil and climate, at which experiments, appropriate to each section, should be con- ducted ; but a large class of experiments must be conducted by farmers themselves to determine the local application of principles. Charts should be sent out by the stations, giving not only the character of experiments to be conducted by farmers, [405] SCIENTIFIC MANUAL. 119 but detailed directions, embracing a clear statement of the questions to be asked, and the precautions to be used, to make the results reliable, and the correct interpretation of the answer possible. Perhaps the most important of the list of experiments enumerated, is that designed to ascertain what elements cf plant-food required by plants, are not supplied by the soil. On soils in good " condition," the answer to this ques- tion would not be very definite, since such have an accu- mulated stock of available plant-food ; but on soils that are exhausted in the agricultural sense, the answer would be readily interpreted, since, in such, there is little more than their "natural strength," and the effects of different fertil- izing substances, either singly or in combination, will be marked, and the results readily interpreted. Soils that have become so far exhausted as to refuse to return remunerative crops for the labor of the husbandman, are defective in one or more of the necessary elements of plant-food in available form, which must be restored before such soils can again become productive. They may have stiil remaining a sufficient supply of some of the elements in an available form, or they may be defi- cient in all. The problem, therefore, is to ascertain what substances are deficient in the soil. The object of experi- ment No. 1 is to ask nature just this question. The farmer, in order to do this, applies to one part of the soil under investigation potash alone, to another phosphoric acid, to another nitrogen, to another potash and super- phosphate, to another nitrogen and potash, to another ni- trogen and phosphoric acid, to another potash, phosphoric acid and nitrogen together, to another lime, etc., with un- fertilized plats between to detect any want of uniformity in the strength of the soil. To make the experiment accurate and reliable, the pre- paration of the soil and the cultivation of the crop should be identical on every plat ; the distribution of each fertili- 1*20 DEPARTMENT OF AGRICULTURE — GEORGIA. [406] zer absolutely uniform throughout its plat, and the same number of plants should grow upon each. An accurate record should be kept of the date and man- ner of preparation, the application of fertilizers, planting, each cultivation and the seasons ; and the crop, when ma- ture, should be gathered and accurately weighed from each plat separately. If there is an abundance of potash already in the soil, and in an available form, there will be no in- crease in the crop from its application ; if deficient, the in- creased production from its use will indicate that it was needed. If the increase is still greater from the use of potash and phosphoric acid combined, this result will indi- cate that both of these substances were deficient in the soil. If a still greater increase results from the use of nitrogen, phosphoric acid and potash combined, this result will indi- cate that J&e soil was deficient in all three of these sub stances. If there is no increase of the crop, as the result of the use of any one of the substances, the indications are that the soil contained a sufficient amount of that substance for the production of the crop upon which the experiment was made. This experiment, if carefully conducted for several years on any particular soil, will very clearly indicate what fer- tilizing substances are needed in that soil. It must, how- ever, to be reliable, be conducted on each variety of soil, and by each farmer for his own information, since one soil may be deficient in one substance, and perhaps the adjoin- ing field, or even another part of the same field, be deficient in another. Every farmer should conduct such experiments on every variety of soil on his farm. They cost but little, and may save him the expense of purchasing, in the so- called complete fertilizers, costly substances with which his land is already well supplied. [407] SCIENTIFIC MANUAL. 121 CHAPTER X. FARM DRAINAGE. This consists in the removal of surplus water from agri- cultural lands by means either of open ditches, or cov- ered conduits, constructed a few feet below the surface of the ground. The natural drainage of some soils is sufficient to carry off promptly all surplus water without the aid of artificial means, but where this natural drainage is, to a large extent, from the surface, it is extremely injurious, and often ruin- ous to the land. If, however, the subsoil is sufficiently pervious to allow the surplus water to sink rapidly below the ordinary range of the roots of plants, and thence to pass freely off to streams, the natural drainage is perfect, and favorable to the growth of vegetation, unless both soil and subsoil are too coarse to admit of the rise of moisture by capillary attraction, and a reasonable atomic absorption and reten- tion. If the soil and subsoil are clay or loam, and the natural drainage perfect, we have the necessary conditions prece- dent to "high farming." In cases where artificial drainage is necessary, the first thing to be considered is HOW TO START. \ This will depend upon the source of the evil, the topog- raphy of the surface, and the character of the subterranean strata. The sotirce of the evil on bottom lands is often found in numerous small springs at the base of the adjacent hills, none large enough to justify open ditches or to make use- ful springs. In such cases an impervious stratum of clay is usually found a few feet below the surface, which pre- vents the water from passing off below, and consequently 122 DEPARTMENT OF AGRICULTURE — GEORGIA. [408] causing It to saturate the soil, and even to rise and stand upon the surface. In such cases the first duty of the land owner is to ex- amine the ground to see if an outlet can be gotten for the drains, and what fall can be had. Many farmers supposing that an open ditch through the center of the swamp, caused by these pent-up springs, will effectually drain it, finding their mistake after the ditch is cut, abandon the undertaking without further effort. In order to drain such swamps, the sources of the evil must be sought out, and the water collected into under- ground drains at the foot of the hill, before it has an op- portunity to saturate the soil below. If the substrata un- derlying the hills from which this water oozes are exam- ined, there will usually be found either one of rock or im- pervious clay continuous under the hill, but terminating at its base. The water, which falls upon the hills, percolates to this impervious stratum, follows its surface to its termination on the edge of the bottom, where, if not collected and carried off by ditches or underdrains, it saturates the soil and produces a swamp. Similar oozy places, occasioned by the cropping out of impervious subterranean strata, are sometimes observed on the siJes of hills, causing below them either barren galls or gullies. In all such cases the remedy must be sought in the collection of the water into underdrains before it reaches the surface, and conducting it to a main drain or open ditch. WHERE DRAINAGE IS NECESSARY. It is a grave mistake to suppose that only swamp hnds, or those which are too wet during the whole or the greater part of the year, require drainage. All lands through which rain water is unable to percolate freely, or in which it either stands for any considerable time on the surface, cr [409] SCIENTIFIC MANUAL. 123 stagnates within lass than three feet of the surface, will be materially benefitted by drainage. The following extract is from " Barrall on Drainage," under the head of the "External Signs of the Want of Drainage." He says: "The aspect of the soil after heavy rains, or great protracted heat, the mode of culture, and the nature of the vegetation are very conspicuous characteristic signs, by the help of which we can easily tell that a ground needs to be drained. " Wherever after a rain, water stays in the furrows ; wherever stiff and plastic earth adheres to the shoes ; wherever the foot of either man or horse makes cavities that retain water, like so many little cisterns ; wherever cat- tle are unable to penetrate without sinking into a kind of mud ; wherever the sun forms on the earth a hard crust, slightly cracked, and compressing the roots of the plants as into a vice ; wherever three or four days after rain, slight depressions in the ground show more moisture than other parts ; wherever a stick, forced into the ground, one foot and a half deep, forms a hole like a little well, having water standing at its bottom ; wherever tradition consecrated, as advantageous, the cultivation of lands by means of convex, high, large ridges ; one may affirm that drainage will pro- duce good effects." In addition to the above indications, the growth of certain plants known to thrive only on soils that are wet, or have stagnant water near the surface, will usually indicate to the farmer the soils that need draining. It is frequently the case, however, that soils which arc sufficiently drained, when first cleared, to produce healthy and abundant crops, become wet and sour after some years of cultivation. This has been observed, no doubt, in the experience of many farmers in Georgia. Such soils when first cleared are drained by the roots of trees, which gradually decay, leaving ducts through which drainage water passes off to pervious strata below. 124 DEPARTMENT OF AGRICULTURE— GEORGIA. [410] After some years of cultivation, however, these ducts become closed, and the water, unable to pass off through them, stagnates near the surface, and injures both the soil and the crops planted upon it. The only means of restoring such lands to fertility, will be found in underdrainage. WHAT DRAINAGE DOES. 1. // carries off stagnant water fiom the surface. — Water can only stand upon the surface of the soil when that under- neath is saturated. As soon as the water is withdrawn from below, that upon the surface must descend, to obey the great hydrostatic law that water "seeks a level," until the surface is entirely relieved. If not removed by drainage, it must pass off by the slow and cooling process of evapo- ration. It is stated that about "four times the amount of heat is required to convert water into vapor, that is required to bring it to the boiling, from the freezing point." Just in proportion, therefore, as the evaporation is greater from underdrained than from drained soils, is there a waste of heat. The drainage of soils which are so wet as to cause water to stagnate on the surface, involves the conversion of abso- lutely useless into valuable property. 2. It removes surplus water from under the surface, lower- ing the water level to the depth at which the drains are laid. None of our cultivated plants except, perhaps, rice, thrive on soils in which their roots find stagnant water near the surface. Besides, stagnant water seems to be no less noxious to our cultivated plants than to animal life, and, though it may supply moisture to the soil, it seems not only to be unable to supply wholesome nutrition to plants, but to contain substances which are positively injurious. The roots of plants grown upon undrained land, are there- fore, compelled to occupy only that portion of the soil which lies above the water line, which is saturated in wet [411] SCIENTIFIC MANUAL. 225 seasons, and baked in time of drouth. Drainage removes the surplus water, increases the area in depth which the roots may occupy, admits a free circulation of air, and hence, a full supply of oxygen to the roots, and prevents the baking of the soil in times of drouth, while moisture and fertilizing gases are absorbed from the air. Again the water line being lowered, rain water, impregnated with am- monia and fresh oxygen, carries these and its warmth into the soil to refresh the roots of plants. Again, as in the case of the surface water, the evaporation is reduced by the removal of the " water line " to a greater depth. 3. By removing surplus water, and lessening the evapo- ration from the surface, warm air and rain water are allowed free access to the depth at which the drain is laid, and con- sequently the soil is warmed, as well as dried ear- lier in the spring, and, by affording earlier the necessary conditions of germination, the season of growth is practic- ally lengthened. Every farmer has observed that gravelly or loamy soils, that are naturally underdrained, can be planted from ten to fifteen days earlier than stiff clays, which hold the surplus water from the heavy spring rains. This is just the difference between drained and undrained lands. Ten days difference in the date of maturity of two fields of wheat, will often determine the question of success or failure. Rust is the greatest enemy of the wheat crop in Georgia. The only safeguards against this are early maturity and thorough drainage. Ten days difference in the time of planting corn will often enable the earlier planting to escape a ruinous drouth. The market gardener who gains ten days in the maturity of his products, by having his lands thoroughly drained, will soon drive his less progressive neighbors out of the market. 4. It deepens the soil, by allowing the rapid percolation of water, a free circulation of air, the deep penetration of roots 120 DEPARTMENT OF AGRICULTURE— GEORGIA. [412] of plants and insects, and facilitates chemical action in the decomposition of mineral substances, previously protected by water. The father of drainage in America, Mr. John Johnston, of New York, said, in a communication on this subject, in 1854: "Last spring I concluded to plow a clay field, con- taining forty acres, only once for wheat, and that after har- vest. Previous to draining, it was one of my wettest fields, and in dry weather, even in April and May, was very haid to plow, often having to get the coulters and shares sharp encd every day, when we used wrought iron shares. "Owing to the great drought before, during and after har- vest, I got a large plow made, so that I could put two or more yokes of cattle and a pair of horses to it, if neces- sary. "Immediately after harvest we started for the field, oxen and drivers, plowmen and horses, and, besides new shares on the plows, took other new shares along, expecting to be obliged to change every day. "When we got to the field, I had one man put a pair of horses before the large plow, and try to open ihe land with a shallow furrow. He went seventy rods away and back, without even a stop, except when the clover choked the plow. I then put the plow down to eight inches, and after one round, to nearly ten, and we went around without any trouble. I then had one yoke of oxen put behind my smallest horses, and a pair of horses before each of my other plows, and they plowed the field with perfect ease, only changing shares twice. "Although the field was undoubtedly plowed at the rate of nine inches deep, yet the clover roots went deeper, and the land plowed upas mellow as any loam ; whereas, had it not been drained, it would have broke up in lumps as large as the heads of horses or oxen." 6. It warms the soil in spring, by allowing the rain water, which has been warmed by passing through the air, to per- [413] SCIENTIFIC MANUAL. 127 colate freely to the depth of the drain, and prevents the loss of heat incident to the slow evaporation of water stagnated in the soil or subsoil. 6. It carries doivn to the roots of plants soluble plant- food, that would, without the drainage, be carried off in surface- water to the gullies and streams. Liquid barnyard manure, filtered through clay, comes out deprived of all coloring matters. Rain water absorbs fertilizing gases from the air during its descent, and takes up soluble matters from the surface, and carries them into the soil, where they are absorbed and retained for the use of plants. 7. It prevents the winter- killing of small grain, by carry- ing off the surplus water, which would otherwise saturate the surface soil, freeze, and break the roots of the plants. 8. It prevents tlie injurious effects of drouth, by affording a deeper range for the roots, and thus removing them from the influence of sudden changes of season. It prevents injury from drouth, also, by admitting a free circulation of air, from which moisture is condensed and absorbed by the fine particles of the soil. 9. It increases the effects of manures, by admitting their more uniform distribution through the soil, preventing their parching effects in periods of drouth, and the leaching influence of stagnant water and surface drainage, occasioned by excessive rains on undrained lands. As a result of this and other circumstances, it improves the quality and in- creases the quantity of the crops produced. The most important question to be considered and de- termined by individuals, after a full consideration of sur- rounding circumstances, is, WILL DRAINAGE PAY ? Not only individual, but general experience, in the coun- tries that have most generally adopted underdrainage, in both field and garden, answers this question in the affirma- tive. It is stated that the crops of England have been doubled by drainage, and the results, as far as it has been 123 DEPARTMENT OF AGRICULTURE — GEORGIA. [414] tested, in this country, are most satisfactory. There are no known reasons why it will not pay as well in Georgia as elsewhere. WHERE TO BEGIN. Bottom lands, which are saturated by the water from pent-up springs, issuing from the adjacent bluffs, will nat- urally furnish the most conspicuous candidates for treat- ment, since the necessity for drainage is most obvious in such localities. The benefits derived from draining these will naturally suggest an extension of the system to up- lands which are saturated and cold until late in the spring. DRAINING MATERIAL. Tile is, without doubt, the best material, as regards effi- ciency and permanence, but its cost is so great as to amount almost to prohibition. Rock is the next best, where it is accessible, and a firm botton to the drain can be had. If the drains have a constant flow of water, so that the material will be kept constantly wet, common pine poles, from four to six inches in diameter, answer well, if the bottom of the drain is firm clay. If the bottom is soft or sandy, it will be necessary to rest the poles upon a plank or slab, to prevent them from sink- ing into the ground, or the sand and mud from washing down and stopping the drain. Three poles are required, two to rest upon the bottom of the drain, cne on each side, and the third to rest between and upon these, as represented in the accompanying figures. The ends of the poles should be cut at " right angles to the length, so as to fit well against each other, and the ends of no two poles should rest at the same F.'g. \b—End %U\m of Pole Drain. Fig. IG—Sid* View of Pole Drain. [415] SCIENTIFIC MANUAL. 129 point. The poles, after being adjusted to each other as ac- curately as possible, should be covered with pine straw, or some similar material, well packed down, to prevent fine earth from passing between the poles into the duct. These poles, if kept constantly wet, will last twenty years, but if alternately wet and dry, they decay very rap- idly, but will even then maintain their integrity, and make an effective drain for eight or ten years. Trough Drains, where lumber is very cheap and accessi- ble, answer a good purpose without foot planks, on clay bottoms, or with them on soft or sandy bottoms. Strips one inch thick, and half of them three, and the others four inches wide, nailed together, so as to form a trough, which, inverted in the bottom of the ditch, forms a cheap and effective drain. If the bottom of the ditch is> firm clay, these may rest upon the soil ; if the bottom is sandy, they should rest upon a foot-plank, laid in the bot- tom of the ditch. The figures 17 and 18 represent such a drain with and without the loot-plank. ~-^r- The planks should be all of the same / length, but put together so that one / p'ank of each, / trough shall lap / six inces over that on the opposite side of the next. (See fig. 19.) If Fig. 17. foot - planks are Fig. 18. Fig. 19. used, the joints of the troughs should be placed over the centres of the former. Rock^drains are expensive, unless the rock is on the sur- face and convenient to the proposed drain. Surface rocks 10 130 DEPARTMENT OF AGRICULTURE — GEORGIA. [416] that are in the way of cultivation, may be thus utilized, while they are being removed from the cultivated field. There are several methods of utilizing rock for drainage purposes, among which are shoulder drains, in which a shoulder is left on each side of the bottom of the ditch, two or three inches wide, with a trench in the center three or four inches wide at the top, according to the volume of water to be discharged, and tapering to two inches in width at the bottom. This center excavation need not be more than four inches deeper than the shoulders. Rocks are laid across the centre opening, so as to rest on the shoulders on each side, and straw, sod, or pounded rock, placed above, to exclude fine earth from the centre ditch. This kind of drain can only be used where the bottom of the ditch rests upon very firm clay. Shed d?-ains, in which one edge of the rock rests on one side of the bottom of the drain, and the other against the opposite side. Fig. 20— Shoulder Drain. Fig. 21— Shed Drain. These too will only answer in very firm clay. Box Drams, in which rocks are set against the sides of the ditch, and others placed across them to form the roof of the drain. For this drain the bottom of the ditch must be wider than is necessary for either the shoulder or shed drain, since it is not generally practicable to secure uniform flat rock. [417] SCIENTIFIC MANUAL. 131 If the bottom is sandy, foot-rocks must be used, to pre- vent the side-stones from sinking into the earth and stop- ping up the duct ; besides, unless the bottom of the ditch is firm clay, it will wash in some parts and stagnate in oth- ers, forming deposits of sand and mud, and eventually fill up the duct. Fig. 22— Box Drain with Foot-rock. Fig. 23— Box Drain with- out Foot-rock, Pounded rock, in which the rock is broken into pieces ranging from the size of a guinea egg to that of a large hen egg, and thrown into the bottom of the ditch from six to ten inches deep. The difficulty about this drain is the danger of choking, in consequence of there being no con- tinuous duct to carry off the water. Tile drain, though expensive in first cost, is by far the most effective and permanent, and though the tile pipe costs more than other material, the ditch for the reception of the tile is less expensive than that for rock, poles or plank, since the bottom of the ditch need not be larger than the outside diameter of the tile used, and the top no wider than is necessary to admit the operator in opening the first two feet, the balance being dug with long-handled narrow instruments, made for the purpose, and the tile low- ered by a "tile layer," the operator standing on the surface of the ground, while opening the bottom of the drain and laying the tile. The following cuts show the implements made expressly for opening drains for tile, the tile-layer, guages and span-level : 132 DEPARTMENT OF AGRICULTURE — GEORGIA. [418] Fig. 24. Fig. 25. Fig. 26. [419] SCIENTIFIC MANUAL. 133 The spades and scoops explain themselves. After the ditch is prepared for the reception of the tile, the operator, standing upon the bank, inserts the arm of the tile layer into the pipe, lowers it, and adjusts it to its place. The gauge is used to secure uniformity in the width and depth of the drain. The span-level is used to determine the exact fall of the drain. It is useful to ascertain the amount of fall the topography of the ground will afford, the proper location of the drains, and the uniformity of the fall in the bottom of the drain, while being dug. Klippart, in his "Land Drainage," page 393, thus de- scribes this useful instrument : "Three narrow strips of board are required, each about six feet in length ; these are nailed together in the form of the letter A, the span or stretch being exactly half a rod. From a nail or pin at the top, a plummet is suspended. It is then placed, for the purpose of marking, upon a floor or piece of timber, which is perfectly level, and the place where the plumb-line touches the cross-bar marked. One foot is then raised one-fourth of an inch, and the place where the line crosses the bar again marked, and will show a rise or fall of one-half inch to the rod. The foot is then raised to half an inch and the bar marked, indicating one inch to the rod. These markings can be made to any extent de- sired, and the instrument, by dropping it into the drain occasionally, will show that the drain is dug with uniform fall, and precisely that determined on at the outset." This is a simple and cheap instrument, which will be found useful on the farm for other purposes than that of drainage. Clay suitable for drain tile may be found in every section of Georgia where fine brick can be made. It should be free from pebbles, and not too poor in clay. A small amount 134 DEPARTMENT OF AGRICULTURE — GEORGIA. [420] of lime, evenly distributed through the clay, will serve as a flux in burning the tile. If there is too much clay, the pipe will be liable to warp or crack in drying. Machines for manufacturing drain tile cost about $250. The tile is made in pieces from one foot to eighteen inches in length Tile having IJ inches inside diameter cost, at present, $18. 00 per thousand feet, but can be made much cheaper on the farm. The forms principally used are the sole and the round tile. The former is objectionable on account of the lia- bility to warp at right angles to the flat side, and thus in- terrupt the continuity of the fall. While the round tile is not less liable to warp, it can be laid on the side of the warp and thus secure uniformity of fall. They are sometimes made with unbeveled edges, and united by collars ; but the cost of the latter is so great, the beveled edges are preferred. If the inside of one end of each pipe is beveled, and the outside of the other, the union is sufficiently exact to pre- vent displacement, and the cost of collars avoided. The following cuts will sufficiently illustrate the different forms : Fig. 27 —Hound tile with collar. Fig. 28— Sole tile. Bound tile with inside bevel. Fig. 29. Same with outside bevil. The question is often asked, H How does the water get into the pipe?" When the number of joints in a given [421] SCIENTIFIC MANUAL. 135 length of 12 or 13 inch tile is considered, and that these joints cannot be made without cement (which is never used) so close as to exclude water, the question contains no difficulty- It is estimated that, in the case of one inch pipe, " the capacity of admission at the joints more than equals the caliber of the pipe every two rods," no fear need, there- fore, be entertained by those using tile pipes for drains, in reference to the water entering the pipe. Those wishing to investigate this subject more in detail should read " Land Drainage," by Klippart, which has been freely consulted in the preparation of this chapter. CHAPTER XL IRRIGATION. In the northern half of Georgia, where there is ample fall in the water courses for the purposes of irrigation, the topography of the country is too irregular to admit of a general system of irrigation. In the southern half there is generally insufficient fall in the streams. Apatt from these considerations, however, the necessity for irrigation will never be sufficiently felt in Georgia to in- duce large expenditures of money for that purpose. By reference to the records given in the '' Hand Book of Georgia," the average annual rainfall for five years, from 1871 to 1875, inclusive, at West End, near Atlanta, is found to be 53.32 inches, and that at Macon 54.88 inches. "From observations through a long series of years, by the Smithsonian Institute, it has been found that the average annual amount of rainfall in the several sections of the State is approximately as follows: North. Georgia, 50 in- ches; Middle and East Georgia, the northern part of south- west Georgia, and southeast Georgia, 55 inches; the mid- 136 DEPARTMENT OF AGRICULTURE — GEORGIA. [422] die portion of southwest Georgia, 60 inches; and the ex- treme southern part of southwest Georgia, 65 inches; average for the State about 54 inches." Not only is there ample rainfall for agricultural purpo- ses, but it is generally quite uniformly distributed through the year. The following table, taken from the " Hand Book of Geor- gia," showing the rainfall for the months of June, July and August, for four years, will illustrate this point : 1873. 1874. 1875. 1876. Months . . . Rainy Days. Hain in inches. Rainy Days. in inches. a * Rain in inches. 3 * Ita i n in inches. June July August 12 8 10 2.22 3.14 3.58 14 13 8 3.85 4.09 3.82 10 8 9 27 3.90 2.12 6.95 14 11 12 9.12 4.49 6.16 Totals .... 30 8.94 35 11.76 12 97 37 19.77 While there is neither necessity nor probability of the adoption of any general and expensive system of irrigation in Georgia, there are many localities in which small areas maybe cheaply and profitably irrigated by individual enter- prise. Notwithstanding the fact, however, that the annual rain- fall throughout the State is ample, and generally well dis tributed through the year, there are occasional drouths of sufficient severity to render it necessary to adopt some means by which their injurious effects upon vegetation may be prevented. By deep and thorough preparation, judicious cultivation, and the preservation of an abundant supply of humus in the soil, but little injury need result from the ordinary drouths of our summers. [423] SCIENTIFIC MANUAL. 137 CHAPTER XII. METEOROLOGY IN ITS RELATIONS TO AGRICULTURE. Although we have no control over either the composi- tion of the atmosphere, or the amount or distribution of rainfall, still it is a matter of some importance that we un- dersVnd the influence exerted by both upon vegetation. The atmosphere supplies to plants nearly the whole of their organic constituents, and affords an inexhaustible source of supply, which can be neither increased nor di- minished by artificial means. It is composed of oxygen and nitrogen, with small quantities of watery vapor, car- bonic acid and ammonia. Notwithstanding the very small per cent, of carbonic acid — l-1600th by weight — contained in the atmosphere, lt is supposed to furnish, through the medium of the leaves and other growing parts of plants, the bulk of the carbon which makes up their cellular structure. Indeed, more than ninety per cent, of the substance of our agricultural plants is derived from the atmosphere. Not only is carbonic acid in large quantity, and ammo- nia in small qnantity, absorbed through the stomata or leaf-pores, but the presence of oxygen is essential to the germination of the seed, and the growth, both of the stem and roots of plants. Again, the fact that air brought into contact with sub- stances colder than itself, is deprived of some of its moist- ure, which is condensed and deposited in the form of dew, renders the atmosphere an important source of moisture to plants, both directly, and indirectly through the medium of the soil. Although plants probably do not absorb moisture direct- ly from the atmosphere, the deposition of dew upon their leaves arrests evaporation, and thus diminishes the drain upon the moisture stored in the soil. 138 DEPARTMENT OF AGRICULTURE — GEORGIA. [424] The farmer, in order to avail himself of the moisture and oxygen from the atmosphere, stirs his soil as deeply as possible, and pulverizes thoroughly, to admit a free circu- lation of atmospheric air. The soil cooling more rapidly than the air at night, robs the latter of its moisture, and stores it to refresh vegetation during the heat of the suc- ceeding day. ^ The importance of the thorough aeration of the soil in cultivated fields is not sufficiently appreciated by our farmers. They are too apt to consider the object of cultivation at- tained when the soil is freed from weeds and grass : yet a crust formed upon the surface of a cultivated field, so as to exclude the air, is more injurious to the cultivated crop than a moderate growth of weeds, accompanied with per- fect aeration of the soil. Soils differ greatly in their powers of absorbing moisture from the atmosphere. Clay soils absorb much more than sandy, and those well supplied with humus more than those deficient in this important substance. Underdrained soils absorb more than those whose sur- faces bake from the effects of evaporation. The absorbent power of soils is influenced by the size of the pores and the character of the particles of which it is composed. The rapidity of absorption depends upon the per cent, of moisture in the atmosphere, while the amount depends upon temperature. The more finely a soil is pul- verized, the greater the surface exposed to the air, and con- sequently, the greater the absorption. The atomic composition of the particles of soil will in- fluence the absorption. If the particles are sand, they can- not absorb moisture, while particles of clay, composed of impalpable powder, have great absorbing power. It is difficult to estimate the beneficial influence upon [425] SCIENTIFIC MANUAL. 139 vegetation effected by moisture absorbed by a finely pul- verized soil. The influence of the moisture of the atmosphere is well illustrated in eastern England, where the average annual rainfall is only about half that in Georgia, and yet by the absorption of moisture from the atmosphere, and the prevention of evaporation, twenty-eight inches of an- nual rainfall there, affords a more abundant supply of mois- ture to vegetation than fifty do in Georgia. Of 27.93 inches of rainfall at Rothamstead, England, 36 per cent, or 10.06 inches, percolated through 40 inches of earth, while at Waushakum farm, near Boston, Mass., only 4.76 inches out of 43.88 percolated through 25 inches of soil. In England, 36 per cent, of the annual rainfall perco" lated through 40 inches of stiffish clay loam, on which no crop grew, while in Massachusetts only 11 per cent of the annual rainfall percolated through 25 inches of light grav- elly loam, upon which grass grew.* The beneficial influence of an abundance of rain and the injurious effects of an excess is well known to every farmer. The rainfall in Georgia is so well distributed throughout the year, that, with the exception of occasional periods of saturation in early spring and drouth in summer, we seldom have an excess, and generally an abundance for agricultural purposes. The extremes are seldom so great as to be beyond the control of the skillful agriculturist. The most interesting fact in connection with the utiliza^ tion of rainfall is, that the same means viz : Under drainage and deep tillage, serve at once to relieve the soil of surplus water and to fortify against drouth. A deficient amount of rainfall may be supplemented by irrigation, but this is usually accompanied by great ex- pense, and, while it may supply water, it cannot effect a uniform distribution, or rob the atmosphere of its warmth * Scientific Farmer— Measurements from Lysimeter. 140 DEPARTMENT OF AGRICULTURE GEORGIA. [426] and fertilizing gases so well as a natural fall of rain. The necessity for an abundant supply of water in the soil is shown by the fact that water is the exclusive vehicle of the mineral food of plants, and that, without a certain degree of dilution of the solution of plant food in the soil, the latter becomes positively injurious. This is plainly shown in the effects of concentrated commercial fertilizers on shallow soils in times of drouth. Again, water is an essential agent, both in the decomposition of vegetable matter in the soil, and of the disintegration and chemical transformation of min eral suhstances, which, though abundant, would, without this agency, be entirely beyond the reach of vegetation. Frost acts an important part in the preparation of min- eral food for plants by the pulverization of rocks, and thus ex- posing their contents to the action of chemical agents. This action of frost is due to the expansion of the water which insinuates itself into the pores of solid substances, freezes, and bursts them asunder. This action exerts a beneficial influence also upon the mechanical condition of compact soils. Evaporation, in our climate, is excessive and injurious in its effects, both upon the soil and vegetation— upon the soil, by lowering its temperature and forming a crust upon the surface, which prevents access to air; upon vegetation, by the too rapid withdrawal of watery vapor from the leaves of plants, causing the wilting and twisting of the leaves observed during periods of drouth or excessive heat. Underdrainage, and deep and thorough pulverization of the soil, are the only practicable preventives of excessive evaporation. Where practicable, mulching is the most effectual pre- ventive of injurious evaporation, but it is only practicable on a small scale. Warmth in conjunction with moisture, oxygen gas and [427] SCIENTIFIC MANUAL. 141 light, is essential to vegetation, and is required in different degrees for the normal development of different plants. The following table taken from."How Crops Grow," shows the results of experiments conducted by Sachs to ascertain the extreme limits of warmth at which the seeds of some of the principal agricultural plants will germinate : Lowest Highest Tej? pf £tur?,of Temperature. Tempeiature. M°stKapicl * Germination. Wheat 41 °F 104°F 84°F Barley 41 104 84 Pea 44.5 102 84 Maize 48 115 93 Scarlet-bean 49 111 79 Squash 54 115 93 The warmth of soils is influenced by various circum- stances, such as texture, color, composition, exposure, drainage, etc. The following table taken from " How Crops Feed," shows the relative "capacity fouheat " of different soils. That of lime sand being assumed as 100. Schubler heated a given volume of soil to 145°F, placed a thermometer in it and observed the time required to cool down to 70°, the temperature of the atmosphere being 61°F. In one column are stated the times of cooling, in another the " relative power of retaining heat, or capacity for heat. " Substance. Time of Cooling. Capacity for Heat. Lime Sand 3 hours. 30 Minutes. 100 Quartz Sand 3 " 27 " 95.6 Clay Loam 2 " 30 " 71.8 Clav Plo*v Land 2 " 27 " 70.1 Heavy Clay 2 " 24 " 68.4 Pure Gray Clay 2 " 19 " ■ 66.7 Garden Earth 2 " 16 " 64.8 Humus 1 " 43 " 49.0 " It will be seen that the sandy soils cool most slowly, then follows clays and heavy soils, and lastly comes humus." The times of warming of the same soils would corres- pond with that of cooling if containing but little moisture and exposed to a low temperature. 142 DEPARTMENT OF AGRICULTURE— GEORGIA. [428 Schubler found also, by experiment, that the same soils blackened and whitened, varied in temperature in about the same ratio as the surfaces of natural color did when alternately wet and dried, so that it seems that dark color exerts about the same influence upon the temperature of a soil that saturation does. Exposure to the direct rays of the sun exerts a marked influence upon the temperature of soils that are identical in every respect. On this subject, Johnson, (in "H. C. F.,") remarks:: " In the latitude of England, the sun's heat acts most powerfully on the surfaces having a southern exposure, and which are inclined at an angle of 25° and 30°. The best vineyards of the Rhine and Neckar are also on hill-sides, so situated. " In Lapland and Spitzbergen, the southern side of hills may be seen covered with vegetation, while lasting or even perpetual snow lies on their northern inclinations." Reflecting surfaces, such as walls and fences, especially if white, influence the temperature of the adjacent soil on the south or east side, and thus hasfen the growth of vege- tation. Gardeners avail themselves of such localities to forward early vegetables. It is a source of regret that no systematic meteorological observations have been made in Georgia until recently. Individuals in some localities have kept records of tem- perature and rainfall for their own information, but while these are valuable, they do not furnish sufficient data to justify deductions of general interest and utility. A system of observations has now been inaugurated under the auspices of the Department of Agriculture, under which observations are regularly made on the tem- perature of the air at 7 a. m., 2 p. m., and 9 p. m., of each day, and an accurate record of both the temperature and the amount of rainfall kept. Transcripts of these records are forwarded to the Department, on the first day of each month, where the consolidated results are tabulated and [429] SCIENTIFIC MANUAL. 143 published. These records are valuable as far as they go, but should, and will be made more complete. The temperature of the soil at different depths should be determined simul- taneously with that of the air, the direction of the wind, at the time of each observation, should be recorded at each station, the pressure of the air should be measured by means of a standard barometer, the moisture of the atmosphere should be measured by means of the hygro- meter, and the amount of percolation of rain water meas- ured by mean* of the lysimeter. The ice has been broken — a beginning has been made, and progress both in accuracy and variety of research will necessarily follow. These records kept for a series of years will be valuable to the agriculturists of the State, and eventually lead to instructive deductions. CHAPTER XIII. ENTOMOLOGY IN ITS RELATIONS TO AGRICULTURE. The injury to vegetation resulting from the depredations of insects in the United Statas is estimated in millions of dollars, and yet very few farmers are able to discriminate between their friends and enemies in the insect world, for we have friends as well as enemies, among these humble inhabitants of our globe. In every department of the animal creation we find pre- daceous animals which live upon their own species. Among animals we have the canines and felines ; among birds, eagles, hawks, etc. ; among reptiles, sharks, crocodiles, etc. ; among fish, the trout and others ; among insects, lady-birds, ichneumon flies, tiger-beetles, wasps, etc. By unceasing warfare upon their enemies among ani- mals, reptiles and birds, farmers have been able to keep 144 DEPARTMENT OF AGRICULTURE — GEORGIA. [430] them in check, and protect their friends ; but the want of the necessary information in regard to the character, transformations and habits of insects, prevents a judicious discrimination between friends and foes, as well as any sys- tematic effort to destroy the latter. While no effort will be made to supply detailed informa- tion in regard to individual varieties, nor even of subdi- visions of the orders into which insects are classified, the design of this chapter is to give to farmers a condensed statement of the principles upon which the science of En- tomology is founded, the basis of the classification of in- sects into orders, the transformations through which those of the different orders pass from the egg to the perfect in- sect, and some insight into the habits of some of those in- sects with which the farmer meets in the prosecution of his avocation. T/ie Science of Entomology is based upon a thorough study of the insect world, in which specific resemblances between different insects are first observed, and those agreeing in particular characteristics grouped together and classified. The classification employed by naturalists is based princi- pally upon the structure of the mouth, in the adult state, the structure and number of the wings, and the transform- ations which the insects undergo in passing from the egg to the adult state. The first great divisions are called orders, of which some naturalists give seven and others eight : They are — 1. "Coleopter a {skeat/iwmged). (Beetles). Insects with jaws, two thick wing covers meeting in a straight line on the top of the back, and two filmy wings, which are folded transversely. Transformation complete. Larvae called grubs, generally provided with six true legs, and some- times also with a terminal prop-leg ; more rarely without legs. Pupa, with the wings and legs distinct and uncon- fined." Some of the coleoptera are friends to man ; such [431] SCIENTIFIC MANUAL. 145 as the lady-birds, tiger-beetles, predaceous ground-bee- tles, and some others, which destroy caterpillars, plant- lice, and other insects injurious to vegetation. Others serve as scavengers, by the removal of carrion, dung, and other filth. Others live altogether on the mushroom fam- ily of plants ; others live under the bark of trees, and in the trunks of old trees, and are injurious, but many of them living mainly upon dead or decayed bark and wood, qo but little damage. There are others still, called blistering beetles (canthari- didae), which are employed in the healing art. 2. "Orthoptera {straight-winged). (Cockroaches, crick- ets, grasshoppers, etc). Insects with jaws, two rather thick and opaque upper wings, overlapping a little on the back, and two larger, thin wings, which are folded in plaits, like a fan. Transformation partial. Larvae and pupae act- ive, but wanting wings." With one exception, all of the orthoptera are injurious, either to household goods or veg- etation. Their larvae closely resemble the perfect insect, and their pupae do not lie in an apparently dormant state like those of the Coleoptera, Lepidoptera, etc., though they shed their skins usually six times during their transformation from the larva to the perfect insect. Unlike insects which undergo a complete transformation, they continue to grow during their transformation, increasing in voracity with their advancement towards maturity, and, unlike the Lep- idoptera, continuing their depredations after maturity. Orthoptera are subdivided into — 1st. Runners, such as earwigs and cockroaches, which are provided with legs suited for rapid motion : 2d. Graspers, embracing mantes or soothsayers, which have teeth on their forelegs suited to grasping other insects, upon which they prey. 3d. Walkers, such as "walking-sticks," which have long 11 146 DEPARTMENT OF AGRICULTURE — GEORGIA. [432] slender legs, capable only of slow motion. They live upon the tender parts of plants. 4th. Jumpers, as crickets, locusts and grasshoppers, whose hind legs are longer than the others, and adapted to quick and long leaping. This is the most prolific, as well as the most destructive, of the Orthoptera. Some of the crickets prey upon other insects, but the principal food of the jumpers consists of the green parts of plants. 4. "Hemiptera {bugs, locusts, plant-lice, etc.) Insects with a homey beak for suction, four wings, whereof the upper- most are generally thick at the base, with thinner extrem- ities, which are flat, and cross each other on the top of the back, or are of uniform thickness throughout, and slope at the sides like a roof. Transformation partial. Larvae and pupae nearly like the adult insect, but wanting wings." Some of the field and house bugs of this order emit very offensive odors, when disturbed. Some live on the juices of animals, and destroy vast numbers of noxious insects. Others are useful in supplying dye-stuffs of great value in the arts. Others, embracing plant-bugs, plant-lice, bark -lice, mealy bugs, etc., that suck the juices of plants, are very injuri- ous, and difficult to destroy. 5. "Neuroptera {dragon-flies, lace-winged flies, May. flies, ant-lions, day-flies, white ants etc.) Insects with jaws, four netted wings, of which the hinder ones are the largest, and no sting or piercer. Transformation complete or par- tial. Larvae or pupae various." Many of this order prey upon other insects both in their larvae and adult states. Dragon- flies are especially useful in destroying gnats and mosquitoes. The lace-winged flies, in the larva state, destroy great numbers of plant-lice. 6. "Lepidoptera — scale- winged, {butter flies and moths.) Mouth with a spiral sucking tube, wings four, covered with brawny scales. Transformation complete. The larvae [433] SCIENTIFIC MANUAL. 147 are caterpillars, and have six true legs, and from four to ten fleshy prop legs. Pupae with the cases of the wings and of the legs indistinct and soldered to the breast." "Some kinds of caterpillars are domestic pests, and de- vour cloth, wool, furs, feathers, wax, lard, flour and the like ; but by far the greatest number live wholly on vegetable food, certain kinds being exclusively leaf-eaters, while oth- ers attack the buds, fruit, seeds, bark, pith, stems and roots of plants." Insects of this order are by far the most injurious, both as domestic pests and as destroyers of vegetation, They pass through four stages, viz : the egg, the larva, pupa and imago, or perfect insect. The instincts of these insects teach them to deposit their eggs where the larvae, the only state in which they are injurious, will have appropriate food as soon as they are hatched. This is illustrated by the conduct of the tobacco fly, which deposits its eggs upon the leaf of the tobacco, tomato, or other plants upon which the larvse feed ; the cotton moth, which deposits its eggs upon the leaf of the cotton plant, and the moth of the corn worm, which deposits its eggs upon the tender bud of the stalk, or the young ears of corn. One of the most remarkable evidences of this instinct is shown by the tent caterpillar, which deposits its eggs in the fall upon the small limbs of those trees which are among the earliest to put forth their leaves in spring. The observant farmer has noticed the partiality of the moth of this caterpillar for the wild crab apple tree which grows in our forests, and, also, that this is the first tree in the for- ests to put forth its leaves in spring. This is the caterpillar which webs in the forks of apple trees in spring, and preys upon the young leaves as soon as they appear. In the fall it is seen in great numbers on the persimmon trees. The cutworm, so destructive in garden and field in spring, belongs to this order. Indeed, the worst enemies to our cultivated plants are found among the Lepidoptera. 148 DEPARTMENT OF AGRICULTURE — GEORGIA. [434] It is important that farmers become familiar with the butterflies and moths which lay the eggs of the caterpillars which are most destructive to vegetation, as well as their habits, in order that the means necessary for their destruc- tion may be used. Tobacco growers destroy great numbers of the tobacco fly by poisoning with cobalt the flowers of the stramo- nium (commonly known as Jamestown weed) upon which the fly feeds at night. Since each female usually lays from 200 to 500 eggs, the importance of destroying the adult insect, if possible rather than the larvae, is apparent. The difficulty attend- ing the destruction of the fly or moth renders warfare upon the caterpillar necessary. The principle distinction between the butterflies and moths is found in the antennas, the position of the wings when at rest, the hind legs, and the times at which they are active. Butterflies have thread-like antennse with knobs at the end, have two little spurs on the hind legs, fold their wings back to back, when at rest, and fly only by day. Hawk-moths have the antennae thickened in the middle, and tapering at each end, wings inclined like a roof when at rest, and hind legs with two pairs of spurs. Some fly by day, but the majority of them only in the morning and evening twilight. Moths have antennae tapering from the base to the ex, tremity, have two pairs of spurs on their hind legs, wings sloping when at rest, and fly mostly by night. Many of the night flyers may be destroyed by fires kept up for a few hours, beginning with early twilight. 6. "Hemenoptera (saw flies, ants, wasps, bees, etc.) In- sects with jaws, four veined wings, in most species the hinder pair being the smallest, and a piercer or sting at the extremity of the abdomen. Transformation complete. Larvae mostly maggot-like, or slug like ; of some, caterpillar like. Pupse with the legs and wings unconfined." [435] SCIENTIFIC MANUAL. 149 In this order are found insects both beneficial and inju- rious to the interests of man. Among them we find leaf- eaters, pine-borers and gall flies that are injurious ; while on the other hand, there are the ichneumon, flies, ants and wasps, which prey upon other insects, and the useful little bee, which labors so persistently in laying up his stores, which are appropriated by man to his own use. The bees and other insects also serve the important purpose of fer- tilizing the flowers of plants, by carrying the pollen from blossom to blossom, in their search for honey. 7. "Diptera." {Mosquitoes, gnats, flies, etc). Insects with a horny or fleshy proboscis, two wings only, and two knobbed threads, called balances or poiser, behind the wings. Trans- formation complete. The larvae are maggots, without feet, and with the breathing holes generally in the hinder ex- tremity of the body. Pupae mostly incased in the dried skin of the larvae, sometimes, however, naked, in which case the wings and legs are visible, and are found to be more or less free or unconfined." In this order are sever- al species which are extremely annoying to man in sum- mer, such as mosquitoes, gnats, and various kinds of flies, including the house fly, blow -flies, flesh-flies, and the cheese fly, which produces skippers. Among those injurious to vegetation we find the Hes^ sian fly, so destructive in its larva state to wheat. There are still others, which have no common name, which deposit their eggs among plant lice or in the nests of other insects, where they either destroy the young, or subsist upon the food stored up for the use of the young when hatched, and thus starve them to death. These seven orders embrace with sufficient accuracy those insects which from their injury or benefit to man, re- quire the attention of agriculturists. The limit to which this work is necessarily circumscribed, forbids the enumeration of the subdivisions of these orders, or detailed descriptions of individual varieties. 150 DEPARTMENT OF AGRICULTURE — GEORGIA. [436] The importance, to farmers, of some knowledge of the classification, transformations and habits of insects injuri- ous to vegetation, and the necessity for the means of dis- tinguishing between friends and enemies, rendered it prop- er that the subject should not be omitted in a work of this character. If what has been written shall have the eflect of stimu- lating careful and accurate observation and investigation of insects on the part of the farmers of the State, its princi- pal object will have been accomplished. Any farmer who will review his experience, and estimate the injury to his crops by insects during the last decade, will be forced to appreciate the importance of utilizing the information sup- plied by the science of Entomology. "Insects Injurious to Vegetation," by Harris, has been freely quoted, and information derived from it utilized. Those desiring more detailed information to aid them in heir investigations, will do well to secure this work. In the preparation of this work, the following works have been freely consulted, viz: How Crops Grow and How Crops Feed— Prof. S- W. Johnson; Scientific Agriculture— Prof. E. M. Pendleton ; Elements of Agriculture, Chemistry and Geology — Prof. F. W. Johnston ; Talks on Manures — Mr. Joseph Harris ; Land Drainage— Prof. John H. Klippart ; Structural and System- atic Botany — Prof. Asa Gray. The principal engravings have been copied from Johnson, Gray and Klippart. APPENDIX For convenience of reference, the following tables are copied from "Talks on Manures," by Harris. Mr. Harris says of them: 11 The following tables of analyses are copied in full from the last edition (1875) of Dr. Emil Wolff's Pracktische Dungerlehre. "The figures differ materially, in many cases, from those previ- ously published. They represent the average results of numerous reliable analyses, and are sufficiently accurate for all practical purposes connected with the subject of manures : In special cases, it will be well to consult actual analyses of the articles to be used." 152 DEPARTMENT OF AGRICULTURE — GEORGIA. [438] I— TABLES FOR CALCULATING THE EXHAUSTION AND ENRICHING OF SOILS. A. -HARVEST PRODUCTS AND VARIOUS MANUFACTURED ARTICLES. Average quantity of water, nitrogen, and total ash, and the different ingredients of the ash in 1,000 lbs. of fresh or air-dried substance. Substance. I— .Hay. Meadow Hay Rye Grass Timothy Red Clover Red Clover, ripe.... White Clover Alsike Clover Crimson Clover Lucern Esparsette Yellow Clover Green Vetch Hay. Green Pea Hay Bpurrey II.— Grken Fodder. Meadow Grass in bloom Young Grass Ryegrass Timothy Grass Rye-Fodder Green Oats Green Corn-Fodder.., Sorghum Moharhay Red Clover in blossom M " before ' White Clover Alsike Clover Crim-on Clover Lucern Esparsette Yellow Clover Green Vetch Green Peas Green Rape Spurrey III.— Root Crops. Potatoes Jerusalem Artichoke. Mangel-wurzel Sugar Beets Turnips „. Carrots Russia Turnips Chiccory Sugar Beet, upper part of root 143 143 143 160 150 165 160 167 160 167 167 167 167 167 700 800 734 700 760 810 822 773 700 780 830 805 820 815 740 80) 830 820 815 870 800 750 800 880 815 920 850 870 800 840 15.5 16.3 15 5 19.7 12.5 23.2 24.0 19.5 23.0 21.3 22.1 22.7 22.9 19.2 3.4 3.2 1.8 1.6 1.8 2.2 2.1 2.5 2.0 51.5 58.2 62.1 56.9 44.0 59.8 39.7 50.7 6i.l 45.8 55.7 83.7 62.4 56.8 18.1 20.7 20.4 21.6 16.3 18.8 12.0 13.0 13.9 13.7 14.5 13.6 8.8 12.2 18.7 12.1 14.7 18.1 13.9 12.2 9.4 9.8 7.5 7.1 7.3 7.8 11.6 6.7 9.6 13.2 20.2 20.4 18.3 9.8 10.1 11.0 11.7 15.3 13.P 11.9 28.3 23.2 19.9 4.6 11.6 7.2 7.4 6.3 7 5 4.3 3.6 5.0 4.4 5.3 2.3 64 2.8 4.6 3.4 3.2 61 5 1 4.0 4.3 S*d tS a .~ y CO *< Z< 3 a a a, 8 % CG j fl cu 00 2.3 8.6 3.3 4.1 2.1 2.0 4.3 1.3 6.2 2.3 1.5 4.5 1.9 7.2 1.8 1.2 20.0 6.1 5.6 1.7 1.4 15.6 6.8 4.3 J. 3 4.5 19.3 6.0 8.4 4.!' 1.2 13.5 5.0 4.0 1.6 4.3 16.0 3.1 3.6 1.3 1.3 26.2 8.3 5.5 3.7 1.5 16. S 3.0 4.6 1.4 1.3 32.6 2.1 4.3 ..0 5.6 22.8 5.4 10 7 2.8 2.3 15.6 6.3 6.8 5.1 4.6 10.9 6.9 8.4 2.0 0.8 3.0 1.1 1.5 0.8 0.4 2.2 0.6 / 2.2 0.8 0.7 1.5 0.4 2.2 08 05 1.6 0.7 2.5 0.6 0.1 1.2 05 2.4 02 0.6 1.2 0.6 1.7 0.6 0.5 1.6 1.4 1.3 0.4 1.8 1.2 0.5 0.8 04 0.3 1.4 1.3 0.8 0.5 0.3 48 1.5 1.4 0.4 0.3 4.2 1.5 1.7 0.3 1.0 4.4 1.4 1.9 1.1 0.3 3.0 1.1 0.9 0.4 1.0 3.8 0.7 0.9 0.3 0.4 7.9 1.0 1.6 1.1 0.4 4.4 o.s 1.2 0.4 0.3 8.6 0.6 1.1 0.3 1.2 4.9 1.2 2.3 0.6 05 3.5 1.4 1.5 1.1 04 2.7 0.5 1.4 17 1.0 2.3 1.5 1.8 0.4 0.2 0.2 0.4 1.6 0.6 1.0 0.3 0.3 1.4 0-5 1.2 0.3 0.3 0.6 0.2 0.7 0.4 0.5 08 0.3 0.7 0.8 0.3 0.9 0.8 1.7 09 04 1.0 05 1.2 1.3 0.3 1.7 1.5 1.1 0.5 0.3 0.8 0.5 2.3 0.9 1.1 1.2 0-7 I [439] SCIENTIFIC MANUAL. 153 Substance. IV.— Leaves & Stems of Root Chops. Potato Vines, nearly ripe Potato Vines, uuripo ... Jerusalem Artichoke.. Mangel-wurzel Sugar Beets Turnips Carrots Chiecory Russia Turnips.... Cabbage, white.... Cabbage Stems.... V. — Manufactured Products & Refuse Wheat Bran Rye Bran Barley Bran , Oat Hulls Pea Bran Buckwheat Bran..., Wheat, Flour Rye Flour Barley Meal Corn Meal Green Malt Dry Malt Brewer's Grains Beer Malt sprouts Potato Fibre Potato Slump Sugar-beet Pomace. Clarifying Refuse..., Sugar-beet Molasses.... Molasses Slump Rape-cake 1 iuseed Oil-cake.... Poppy-cake Beach-nut-cake Walnut-cake Cotton-seed-cake ...., Cocoanut-cake. Palm-otl-cake VI.— Straw. Winter Wheat Winter Spelt Winter Rye Spring Wheat Spring Rye Barlev Oats..". :. Indian Corn-stalks... Buckwheat Straw Pea Straw Field Bean Garden Bean Common Vetch Lupine Rape Poppy 4.9 5.8 5.8 8.0 8 0 3.0 5.1 8.5 4.6 2.4 1.8 22.4 23.2 23.7 27.2 18.9 16.8 16.0 16.0 10.4 16 0 7.8 86.8 1.8 1.6 2.9 0.8 12.8 3.2 48 5 45.3 52.0 38.1 55.3 39.0 87.4 25.9 4.8 4.0 4.0 5.6 5.6 6.4 5.6 4.8 13.0 10.4 16.3 12.0 9.4 5.6 19.7 16.5 14.5 14.1 18.1 11.9 26 0 16.5 25.3 16 0 11.6 53.5 71.4 48.4 34.7 22.7 34.6 7.2 16.9 20.0 5.9 14.6 26.6 11.7 14.3 19.3 8.1 4.9 10.3 11.2 2.6 6.5 5.8 1 7 2.5 4.6 0.5 6.2 2.1 66.7 20.6 1.8 0.3 5.0 2.2 11.4 3.9 3.3 0.8 82.3 57.5 14.0 11 0 54.6 12.4 50.8 12.4 70.9 23 43.3 6.5 46.2 14.3 58.4 14.6 55.1 22.4 26.1 5.0 46.1 6.3 50.1 5.2 40.5 7.8 38.1 11.0 46.6 11.2 41.3 9.4 40.4 8.9 41.9 9.6 51.7 24.2 44.0 10.1 43.9 18.5 40.0 12.8 44.1 6.3 41.4 8.0 40.8 11.1 48.7 18.4 0.4 0.8 0.2 2.1) 2.7 l.l 62 2.'.) 1.0 0.9 0.6 0.4 0.9 0.1 10.0 1.5 1.8 0.7 2.3 4.6 1.7 1.2 0.1 1.1 1.8 1.1 3.2 6M 2.6 1.7 2.5 1.8 1.4 4.1 3-4 0.2 0,2 0.6 0.4 0.5 1.0 1.3 0.2 lt9 0.9 0.3 2.6 1.1 4.7 0.2 6.8 4.3 27.0 13.2 3.1 2.7 2.6 3.1 2.7 2.9 3.5 2.6 4.2 3.2 3.6 4.0 9.5 16.2 9.8 11.1 15.6 14.8 11 6 14.7 3.3 2.4 1.3 1.3 2.7 0.5 0.9 0.4 1.0 0.6 0.5 8.8 11.3 3.0 1.0 2.2 4.6 0.4 1.4 2.7 0 1.2 2.2 1.0 0.4 1.8 0.1 0.4 0.7 0.2 0; "7.0 8.1 62 3.6 5.6 8.9 1.6 4.5 1.1 1.2 1.1 0.9 1.8 1.1 1.6 2.6 1.9 3.5 3.3 2.5 3.7 3.6 2.5 S.l &5 1. 1.2 0.7 0. 1.3 0.9 1.2 1.0 2.6 1.4 2.4 27.? 34 3 8.9 1.6 3.1 12.5 3-7 85 9.5 2.6 5.3 9.7 4.1 2.0 18.0 0.4 1.0 1.1 0.2 0.5 0.1 19.2 16.1 31.2 9.7 20.2 28.1 14.9 11.0 2.2 2.6 2.1 2.0 3.0 1.9 1.9 5.3 6.1 3.5 3.2 3.9 2.7 3.7 2.4 1.6 1.3 O.i 0.2 0.6 0.9 1.1 2.0 1.4 30 2.4 0.9 0.1 '09 1.3 0.9 1.0 0.6 0.2 •2.9 "6'.4 0.4 0.1 1.7 0.2 3.2 1. 1.9 0.6 0.6 0.7 2.1 0.5 1.1 1.2 1.1 1.2 1.2 1.5 1.3 1.2 2.7 2.7 1.6 1.7 3.3 3.0 3.1 2.5 0.9 1.2 3.6 05 0.7 0.5 2.9 0.6 2.6 0.2 0.2 0.5 1.4 23.6 23.3 0.9 0.7 4.8 8.8 46 0.6 14.7 0.1 0.2 0.9 0.7 0.3 "2.8 6.4 4.5 0.8 0.7 2.3 1.9 0.8 31.2 36.0 22.9 18.2 26.1 21.5 19.6 11.7 2.9 8.0 3.2 1.9 3.6 2.1 2.6 5.5 154 DEPARTMENT OF AGRICULTURE — GEORGIA. [440] Substance. VII.— Chaff. Winter Wheat Spring Wheat Winter Spelt Winter Rye Barley Awns Oats Indian Corn-cobs.. Field Beans Lupine Rape Flax-seed Hulls... VII r.— Commercial Plants, etc. Flax Stems Rotted Flax Stems., Flax Fibre Hemp Stems Hops, entire plant . Hops Hop Stems Tobacco Leaves , Wine and Must Wine-grounds Grape Stems, etc.... Muiberry Leaves.... IX. — Materials for Bedding. Sedge Grass Rush Beech Leaves, August " " Autumn Oak Leaves, August.., " " Autumn. Fir Needles , Pine Needles , Moss Fern , Heath Broom Sea-Weed X.- -Orains and Seeds. Winter Wheat Spring Wheat Spelt, without husk. Spelt, with husk Winter Rye Winter Barley , Spring Barley Oats Millet Indian Corn Sorghum Buckwheat Field Beans..., Garden Beans , 143 143 143 143 143 143 140 150 143 140 120 140 100 100 150 140 120 160 180 866 650 550 850 180 140 140 560 150 550 150 475 450 250 250 200 250 150 144 143 143 148 143 145 143 143 140 144 140 140 143 145 160 7.2 75 5.6 58 4.8 6.4 2.3 16.8 7.2 6.4 10.0 14.0 20.8 20.5 22.0 16.0 17.6 16.0 16.0 19.2 20.3 16.0 14.4 35.8 40.8 39.0 92.5 121.4 82.7 84.0 120.0 71.2 4.6 54.5 18.1 73.2 54.7 30.4 7.0 6.8 33 2 81.4 66 8 40.7 151.0 2.1 13.9 13.0 16.3 36.7 61.2 48.1 19.0 58.5 15.8 41.7 18.4 32.0 19.2 50.7 16.6 13.6 122.3 16.9 18.3 14.2 36.6 17.9 17.0 22.2 27.0 29.8 13.0 16.0 11.8 23.5 30.7 27.4 8.5 4.8 7.9 5.3 9.4 4.6 2.4 35.3 8.7 11.8 15.4 9.4 0.3 0.3 4-6 20.1 23.0 11.4 17.7 19.0 3.7 2.3 5.4 1.4 1.0 0.6 2.6 18.0 2.1 4.8 15.9 1.7 1.0 (1.2 ().3 1.2 2.9 0.1 1.3 0.7 4.1 3M) 2.7 13.1 12.0 0.4 0.4 0.5 04 0.3 0.7 0.G 0.(5 0.4 0.2 0.5 0.7 0.2 0.4 0.4 1.8 4.0 2.0 3.5 12.7 4.0 0.2 6.8 3.6 363 15.4 3.6 3.6 20.3 18.1 11.1 12.6 62.8 0.1 2.9 4.5 5.4 4.2 26.4 4.1 20.3 6.1 4.3 2.2 6.2 3.6 22 16.7 0.6 0.5 0.4 1.0 0.5 0.2 0.6 1.0 0.2 0.3 0.2 0.5 1.2 1.5 1.8 2.0 0.2 0.3 2.4 6.4 3.7 2.7 17.7 0.1 0.7 0.7 1.0 1.1 2.9 3.1 1.4 3.5 21 1.7 1.1 0.5 1.1 3.5 1.6 1.6 10.0 |2 4.0 3.1 6.1 5.6 24 1.3 0.2 2-7 1.1 3.4 4.5 4.0 0.8 07 2.3 7.5 11.2 4.4 4.8 0.4 2.5 1.6 1.3 2.3 4.6 4.3 1.8 2.4 1.9 3.5 1.0 1.4 0.9 4.2 1.1 1.1 3.8 7.9 8.9 6.0 7.6 8.4 5.6 7:7 6.2 5.9 5.9 8.1 57 8.6 119 9.7 S3 0.7 1.9 0.1 3.5 01 1.2 0.5 7. 3.4 2.0 0.2 o.; 0.7 3.7 2.4 1.3 5.8 0.1 0.6 0.3 0.3 0.6 23 13 0.4 2.1 0.4 1.8 0.4 0.6 1.0 1.8 0.7 0.4 26.3 0.1 0,3 T.i 0.2 0.5 0.4 0.4 0.1 0.2 '6*2 0.8 0.8 1.1 [441] SCIENTIFIC MANUAL. 155 Substance. u (0 "S * d I CO 1 1 o o GO I 2 9 bo o -3 ■9 « 3 02 •0 a . as a 2 9 55 Vetch 143 130 150 150 160 140 146 120 130 125 118 120 130 147 118 122 110 492 560 875 860 450 790 800 790 800 770 780 740 597 662 591 528 672 120 150 44.0 56.6 30.5 31.2 28 0 32.8 26.1 10.2 5.1 5.5 45.3 32.0 29.0 32.0 29.0 360 34 9 84.7 26 6 25.0 22.4 20.0 21 8 94.4 54.0 26 8 34.1 383 33.8 38 4 48.8 45.1 74.8 546 34.6 39.1 34 9 36.5 52.9 32.6 45 3 25.0 12.0 9.6 6.2 84 67 4 7.5 7.1 7.5 7.1 12.6 12 0 10.4 46-6 38.0 31.7 21.6 61.8 9.7 98.8 8.1 10.2 13.5 12.3 11.0 9.1 11.1 14.3 6.5 7.6 9.6 7.7 5.9 7.2 10 0 9.4 7.2 7.1 62 1.5 1-8 2.5 0.6 08 05 1.5 5.2 4.1 3.9 1.7 2.4 1.5 1.8 1.5 1.8 746 2.1 0.1 0 4 0.2 1.1 8.5 4.2 3.5 4.6 0.4 0.6 'To 0.5 0.7 0.4 "o.'i 0.6 0.8 26.6 34 2.9 83 2.2 T.O 0.5 1.4 0.6 1.4 02 1.4 0.3 1.9 2.1 3.0 2.5 2.5 12.3 7.6 10-2 29.1 17.3 6.1 5.5 5.2 7.0 18.7 2.6 10 9 84 1.4 0.7 1.3 2.5 6.9 0.1 0.1 0.1 0.1 0.2 0.2 0.8 20.8 16.3 13.2 9.2 54.0 2.4 4.2 24 40 4.9 39 2.6 8.6 7.8 5.0 5.9 3.1 46 4.7 3.7 50 4.7 2.6 2.1 0.1 05 0.2 0.1 0.2 0.1 0.1 01 0.1 0.4 02 05 0.6 0.5 0.4 0.4 1.0 0.6 1.6 10.0 14.3 14.5 11.6 9-2 7.6 7.5 11.8 16.5 14.0 16.5 14 9 14.6 10.6 13.5 16.9 6.0 2.7 1.4 1.7 8.0 11.5 0.4 0.6 0.4 0.9 4.3 5.8 4.6 18.6 13.8 12.3 8.8 8,7 0.3 1.1 1.0 1.5 0.9 1.6 1.2 2.1 2.0 4.2 2.4 2.5 0.9 2.3 1.8 1.0 0.8 0.1 0.6 0.3 0.4 "o.i "02 0.1 01 0.1 0.4 "o.'i "4.0 03 0.2 0 5 0.8 0.3 1.1 Sugar-Beet 0.8 40 0.6 02 0.5 Summer- Rape "0 9 1.7 0.4 6.5 0.3 0.3 0.1 "6'.2 Hemp... Horse-chestnutSjfresh XI.— Various Ani- mal Products. Cows' Milk Sheep Milk Ox-blood Calf-blood 0.1 Sheep-blood Ox-flesh 0.3 0.1 "61 0.1 0.2 Calf-flesh Swine-flesh Living Calf Eggs 0.1 2 5 3.0 156 DEPARTMENT OF AGRICULTURE — GEORGIA. [442] B.— AVERAGE COMPOSITION OF VARIOUS MANURES. Name of Fertilizes. I.— Animal. Excrements. (In 100 parts of Manure.) Fresh Faeces: Horse. Cattle. Sheep- Swine. Fresh Urine; Horse. Cattle. Sheep. Swine. Fresh Dung (with straw):* Horse 713 Cattle 7 Sheep .. 646 Swine 724 2 S Common Barn-yard Manure : Fresh Moderately rotted Thoroughly rotted Drainage from barn-yard ma nure Human Faeces, fresh . Human Urine, fresh Mixed human excrements, fresh Mixed human excrements, most ly liquid Dove manure, fresh Hen manure, fresh Duck manure, fresh , Geese manure, fresh , II.— -Commercial Manures. (In 100 parts of Fertilizer.) Peruvian buano Norway Fish-Guano Poudrette Pulverized Dead Animals Flesh-Meal Dried Blood.... Horn-Meal and Shavings Bone-Meal Bone-Meal from solid parts Bone-Meal from soft parts 901 14.8 12.6 4.(1 5.7 27.8 14.0 8.5 6.0 5.0 7.0 31.6 17.2 81.1 30.0 28.0 27.4 45.2 15.0 82 21 35.6 25.6 44 58.0 65.0 7 10.7 193 29.9 24 13.5 51 16.0 30 15.0 303 173.0 255 185.0 172.0 134 95.0 51.4 53.4 27.0 56.9 56.6 0 68.5 33.8 31.5 37.3 15. 5 19. 4.y, 45 5.0 5. 1.5 10.0 6.0 7.0 3.5 17.6 16.3 10.0 5.B 13.0 9.0 2.0 6.5 9.7 11.7 10.2 4.0 15.0 4. 22. 8.3 5.2 6.8 5.0 4.0 2.5 2.0 2.1 2.0 10.0 8.5 (3.2 9.5 0.7 0.6 1.5 1.2 3.4 1.3 4.6 1.5 0.9 1.0 0.3 6.2 0.2 0.9 1.0 16.0 24.9 17.0 8.4 I ll .Isi 2.1 2.6 3.0 0.1 10.9 1.7 2.6 17.8 15.4 14.0 5.4 13.0 13-5 2.1 13.9 6.3 1.0 5.5 23 2 25.2 20.0 MM 'u ° - 3 0.2 7.2 0.2 17.5 03 15.0 0.3 1.5 6.5 2.3 17.7 0.4 8.5 1.0 14.7 1.7 10.8 1.7 12. 6 16.8 17.0 0.2 0.2 20.2 4.5 35.2 28.0 14.0 1.7 1.6 5.4; 1.7 1.1 2.1 11.0 lj 3.5 I 3.0 II 3.5 1.5 1.9 1.6 1.2 04 5.0 4.0 4.3 1.3 1.1 1.5 0.2 0.4 0.3 0.2 0.2 * It is estimated that in the case of horses, cattle and swine, one-third of the urine drains away. The following is the amount of wheat straw used daily as bedding for each animal : Horse, 6 lbs.; Cattle, 8 lbs.; Swine, 4 lbs. ; and Sheep, 0.6 lbs. [443] SCIENTIFIC MANUAL. 15 Name of Fektilizer. (In 100 parts.) Bone-black, before used Bone-black, spent Bone-ash Baker Guano Jarvis Guano Estremadura Apatite Sombrero Phosphate Navassa Phosphate Nassau Phosphorite, rich Nassau Phosphorite, medium.... Westphalian Phsophorite .... Hanover Phosphorite Coprolites Sulphate of Ammonia , Nit rate of Soda Wool-dust, and oftal Common Salt Gypsum or Piaster Gas-lime , Sugar-house Scum , Leached wood ashes Wood-soot , Coal-soot , Ashes from Deciduous trees., Ashes from Evergreen trees.. Peat-a&hes ., Bituminous coal-ashes ; Anthracite coal-ashes III.— Superphosphate, from Peruvian Guano Baker Guano..... Estremadura Apatite Sombrero Phosphate Navassa Phosphate : Nassau Phosphorite, rich Nassau Phosphorite, medium ... Bone-black Bone-Meal Phospho-guano (manufactured) .. pr e 10.0 6.6 8.0 9.2 5.4 •V,.0 1.1 24 5 5.0 71.8 70.2 50 5.0 < pr c 84.0 84.0 91.0 81.0 80.0 EM 92.0 97.4 97.5 91.8 94.5 95.7 16.0 15.0 15.0 15.0 15.0 15.0 12.0 15.0 13. Oj 15.5U3.0 41.9 6.2 2.5 8.0 23. S 34.0 95.0 so.s 91.7 41.0 75.0 23.2 24.8 90.0 90.0 95.0 95.0 90.0 42.1 78.8 85.0 85.0 82.5 85.0 88.0 77.0 2 80.3 pr c 1 0.5 pr c 0.1 1.1 0.3 0.2 0.4 0.7 0.8 0.2 0.2 2.5 2.4 0.1 10.0 6.0 1.5 0.5 0.1 pr c 0.3 0.2 0.6 1.2 0.3 0.3 0 0.5 35.0] 0.1 44.3 a pr c 43.0 37.0 46.0 41.5 39.1 48.1 43.5 37.5 45.1 40.1 21.8 37.2 45.4 05 0.2 1.4 1.2 31.0 64.5 20 7 24.5 100 4.0 30.0 35.0 9.5 25.9 28.2 26.4 17.0 26.5 24.2 25.0 22.4 24.0 pr c 1.1 1.1 1.2 1.5 05 0.1 0.6 0.6 0.2 0.2 0.9 0.2 1.0 pr c 32.0 ^6.0 35.4 34.8 20.6 37.6 35.0 33.2 33.0 24 1 19.7 29.2 26.4 1.8 10.5 21.8 22.1 20.2 15.4 19.4 16.6 16.2 16.6 20 5 pr c 0.4 0.4 0.4 1.5 18.0 0.2 0.5 0.5 0.3 1.0 0 5 0.8 5S.0 0.7 0.5 1.4 44.0 12.5 0.8 0.8 0.3 1.7 1.8 1.6 1.8 8.5 5.0 pr c 5.0 15.0 6.5 0.8 0.5 9.0 1.0 5.0 55 20.8 22.0 3.3 7.5 3.0 1.5 29.0 2.0 4.0 3.0 9.1 20.0 4.0 16.0 1S.0 18.0 ? ? ? § pre 0.8 0.2 15 0.6 0.1 3.1 1.5 1.0 0.5 0.1 1.4 1.7 0.2 48.2 0.1 0.3 0.3 0.2 1.1 0.2 0.9 0.4 ? 1.8 1.3 The following is the analysis of South Carolina Phosphate Rock Moisture 1.91 Organic Matter and Water, of combi- nation'- 4.05 Posphoric Acid 26.23 Magnesia 0.24 Lime , 39.78 Potash 0. 20 Soda ,. 0.63 Chloride Sodium 0.05 Sulphuric Acid 2.50 Oxide of Iron 1.85 Alumina, and a little Fluorine 4.64 Insoluble Silicious matter and Soluble Silica 15.31 Carbonic Acid 2.60 100.00 ♦Contains, .Nitrogen 0.09 Equal to Ammonia 0.11 158 DEPARTMENT OF AGRICULTURE — GEORGIA. [444] 3— .TABLE SHOWING THE DISTRIBUTION OF INGREDIENTS IN SOME MANUFACTURING PROCESSES. Name of Material. >> t» P a I 2 J3 00 1 Cm 4 a 3 4 1 9 a to a £ '3 j 1.— Brewing. lbs 855 13.2 lbs 15.2 lbs 22.23 lbs 4.4S lbs 0.58 0.167 0.039 0. 69 1474 lbs 1.92 0.056 0.045 0.066 1 124 lbs 7 71 1.001 0.345 0 168 Distribution of the Ingredients: Water 1.23 2.43 13.0S 0 54 2.27 3.65 9.43 106 0.53 11.02 14.32 5 12 1.28 20.72 12.5^ 7.67 3.41 16.79 9.43 0.54 8.89 16.88 5.50 1.80 9.60 6.10 2.84 3.26 7.10 1.15 1.71 1.20 2.47 0.57 30.36 25.15 4.03 1.22 0.852 0.749 0.580 0 02H 0.643 1.99S 5.69 0.184 O..I92 5.966 4.501 0.883 0.221 5.605 3.941 1.325 1.273 3.993 5.69 0.086 5.604 5.26 1.980 0.648 2.672 1.505 0.247 1.258 3.914 0.336 0.58c 0.38C 1.741 0.87k 9.426 9.17c 0.171 0.054 0.234 33 260 9 30 1.38 8.74 0.653 3.631 0.160. ft nKR 0 062 Teast Beer 2 94 2.14 3.2 0.56 0.28 4 04 14.08 2.82 0.71 17.61 12.32 4.23 4.60 11.95 3.20 0.60 2.60 20.80 14.65 1.64 4.51 4.80 4.53 0.27 1.60 0.24 0.44 0.60 0.32 ) 0.097 0.185 0.484 0.44 0.088 0.0 14 0.572 1.648 0.429 0107 2.184 1.444 0.643 0.367 1.720 0 44 0.042 0.398 2.02 0.458 0.148 1394 0.186 0.02S 0.15S 0.53C 0.131: 0 1 88.0 89.0 89.0 90.0 84.0 84.5 84.0 8S.0 94.0 8S.0 85. C 84.0 95.0 86.0 86.0 86.0 86.0 84.0 84.0 82.5 82.0 84.0 85. C 83. C 12. £ 11. C 8.C 24. C 13. £ 15. ( 7.00 8.00 8.00 4.00 3.00 2.40 2.00 3.00 8.50 1.30 1.70 2.20 2.60 2.85 5..60 6.20 6.60 7.50 6.0u 5.55 5.95 5.00 4.50 5.50 1..00 .68 .68 1.00 .70 ► 1.00 4.92 7.00 5.75 3.38 2.20 1.84 1.63 1.89 5.23 1.13 1.87 1.35 1.60 1.17 6.44 7.52 7.95 1.25 0.88 0.9G 0.85 0.55 0.37 0.48 0.0F 0.i:j 0.11 0.3i 0.1? 0.4S 1.65 3.12 1.76 1.37 1.27 0.96 0.66 0.96 2.12 0.35 0.50 0.55 0.65 0.50 1.46 1.49 1.45 1.3( 1.5C 1.11 0.8S 0.6£ 0.6? 0.9: 0.2.: 0.2i O.U 0.3£ 0.21 0.2 4.75 6.50 5.00 3.80 4.00 3.40 4 20 4.30 4.20 1.80 1.80 1.65 170 2.00 2.60 2.58 2.55 2.60 1.50 0.90 o.co 0-5( 0.6C 0.25 ! 0.22 1 0.18 > 0.3: ) 0.2( > 0.2$ $ 19 72 27 86 21 01 15 65 15 75 18 38 16 75 16 51 18 21 6 65 7 08 Rape Cake Linseed Beans Peas Lentils Malt-dust ^ India Meal Wheat Barley INlalt 6 82 6 65 7 70 Oats ♦Fine Pollard 13 53 tCoaise Pollard 14 36 14 59 9 64 Clover Hs969 3 by 1 15,520 3 by 2 7,260 3 by 3 4,840 W2 by 3K 3,555 4byl...t 10,890 4 by 2 5,445 4 by 3 3,630 4 by 4 2,722 4^by4K 2,151 5 by 1 8,712 5 by 2 4,356 5 by 3 2,904 5 by 4 2,178 5 by 5 1,742 5Wby5K 1>417 6 bv6...~ 1,210 6% by 6^ 1,031 Multiply the distances into each feet in an acre, or 43,560, and the Rural Affair*. NO. OP PLANTS. 888 DISTANCES APART. 7by 7 8by 8 680 9 by 9 537 10 by 10... 435 11 by 11 360 12 by 12 302 13 by 13 257 14 by 14 222 15 by 15 193 16 by 16 170 17 by 17 150 18 by 18 134 19 by 19 120 20 by 20 108 75 69 59 48 27 17 12 10 other, and divide it by the square quotient is the number of plants. — 24 by 24 25 by 25. 27 by 27, 30 by 30 40 by 40. 50 by 50. 60 by 60. 66 by 66. INDEX. A. Acid 8 Acid -Carbonic , 15 Acid— Sulphuric 30 Acid— Acetic 62 Acid— Phosphoric 23 Acids— Vegetable , 61 Agricultural Experiments 114 Albumen — Vegetable 64 Albumen— Animal 63 Albuminoids 63, 65, 66, 109 Albuminoids and Carbo-hydrates, ratio of. etc 110 Alcohol 61 Alkaline Earths 8 Alumina 28 Aluminum , 28 Alum 29 Ammonia 13 Analysis 7—92 Analysis— quantitative , 8 Analysis — qualitative 8 Analysis of agricultural plants 57 Animal products 155 Animal manures— Composition of 159 Anther 51 Appendix 151 Ash elements and their compounds... 67, 74, 75, 88, 89. Assimilation , 48 Atmosphere and plants— Kelation be- tween 57 Atmosphere in its relations to vegetation 80 B. Barium 32 Bedding— Materials for 154 Beetles 144 Bone ash , 22 Bone black 14 Bones— Composition of ( 21 Botany 5 Bromine 32 Butterflies 146 "l4S c. Calcium 26 Cane Sugar 60 Carbon ""'.'.'. 13 Carbonic Acid 15, 82 Carbonate of Soda 26 Carbonate of Lime 26, 27 Carbonic Acid— imbibed by leaves 55 Carbo-hydrates 58 Case-hardening 30 Caseine 64 Caustic Lime. 26 Cell walls 46 Cellulose 46, 58, 59 Charleston Phosphate 21 Chemistry 5, 9 Chemistry— Organic 9 Chemistry — Inorganic 9 Chemical composition of plants 55 Chemical agents 75 Chemical Analysis 87 Chemical symbols 6, 7 Chemical compounds ' 8 < hloride of Lime 28 Chlorine 29 Chloride of Potassium 24 Chilian Saltpetre 26 Chromium 32 Chaff 154 Circulation of sap ""!"" 53 Citric Acid 61 Climate — Influence of 96 Cobalt 32 Coleoptera !.".".. 7. .7. .'.144 Combustion „ 17 Composts 77 Composting Super-phosphate with home manures 164 Composting— Formula for 165 Composting— Directions for 165, 166 Copper 32 Corundum 28 Corn „ 95,112 Cotton 94 Cotton fibre ..' '. 89 Cotton seed 77, 89, 106 Cotton plant and its products 160 Cotton plant— Chemistry of 160 D. Definition of Terms 5 Dextrine 59 Dicotyledons 38 Diptera 149 Directions for Composting 165 Drainage— Effects of 91 Drainage 121 Drainage — Where necessary 122 Drainage— What it does 124 Drainage— Where to begin 128 Drainage— Material for 128 Drains— Different kinds 1*28,131 Dried blood 99 E. Earths— Alkaline 8 Elements— List of 7 Element 5 Endogens 38, 45 Endosmose 41 Entomology "7, 5 Entomology— In its relations to agricul- ture 143 Entomology— Science of 144 Epsom Salts , 20 Essential organs 52 Evaporation— Effects of 140 Excrement 98 Exhalation from plants 82 Experiment 7 Experiments— Laboratory '....'.'.'.'.'.115 Experiments— Field 115 Experiments— List of. 116 Exosmose „ 41 Exogens 38,"45, 46 Exposure— Influence of 144 INDEX. F. Farmyard manure 74 Fermentation 18 Fertilizers 9? Fertilizing agents 98 Fertilizers — Mineral 99 Fertilizers— "Vegetable 104 Fertilizers— Commercial 106 Fish scrap 98 Flower buds 44 Fodder— Green 152 Foods which make rich manure 159 Formula? for composting 165 Frost— Influence of 140 Fruit sugar „ 60 G. General Chemistry 5 Geology 5 Gestation— Period of 168 Glauber salts 20 Gluten .„, 64 Grape Sugar 60 Grasshoppers 145 Grains and seeds [154 Gums 59 Gypsum 20, 28, 103 H. Hawk-moths 148 Hay. 152 Hemenoptera 148 Hemiptera 146 Humus 15, 78 Hydrogen 10 Imbibition 53 Incubation— Period of 168 Inorganic Chemistry 9 Introductory 3 Iron 29 Iron— Cast 30 Iron— Wrought 30 Iron— Galvanized 31 Iron— Pyrites 31 Iron— Sulphate of 31 Irrigation 135 Kainit 24 Lead ?2 Lead— Sugar of 33 Leaf bud- 44 Leaves 48 Leaves— Exhalation from 49 Leaves and stems of root crops 153 Legumes 105 Lepodoptera 146 Lignin 5S Lime 26,76, 77, 78, 79, 101 Lime— Carbonate of 102 Lime— Air-slaked 102 Lime— Sulphate of 103 Litharge 33 M. Magnesium 28 Magnesia 28, 104 Manganese 33 Malic Acid .."".*** 61 Marls 27 Manures— Composition of '. .'.'156 Manures — Composition of Animal 159 Manures— Foods which make rich 1=19 Manufactured products and refuse 153 Manufacturing processes— Ingredients in I08 Mechanical agents 78 Meteorology 5, 137 Mercury 33 Milk Sugar '. 60 Mineralogy 5 Mineral Waters 31 Mineral Plant-food 87 Mineral Elements 88 Mineral Fertilizers 99 Mixture 8 Moths ".146, 148 Monocotyledons 38 Muck 15, 105 N. Neuroptera 146 Nickel 33 Nitrates 12 Nitrate of Potash 25 Nitrate of Soda 100 Nitrogen 12,107 o. Oats 95 112 Object of the work 4 Ochre — Red or yellow 29 Oils— Vegetable 62 Organic Chemistry 9 Organs of vegetation 50 Organs of reproduction 50 Organic substances 55, 56 Orthoptera 145 Osmose 40 Ovary 52 Ovule 52 Oxalic Acid 62 Oxygen 9, 18 P. Paris Green 31 Pea* 95 Peat 14 Petrified wood 23 Pistils 51, 52 Phosphorus 20 Phosphoric Acid 21, 89, 94, 100 Phosphoric Acid— Soluble 22 Phosphoric Acid— Insoluble 22 Phosphoric Acid— Precipitated 22, 23 Phosphoric Acid— Available 23 Phosphate of Lime 28 Plaster of Paris 28 Platinum 33 Plants— Chemistry of 154 Plants— On an acre 168 Plants— Structure and office of different parts 34 Plants— Decotyledonous 38 Plants— Exogenous 38 Plants— Monocotyledonous 38 Plants— Polycotyledonous 39 Plant fertilization 67to 72 Plants as food for animals 108 Plant food 73 Polycotyledons 39 Pollen 51 INDEX. m Potash 24, 89, 100 Potash— Nitrate of 25, 101 Potash— Carbonate of 101 Potash— Sulphate of 101 Potassium 24 Potassium— Chloride of 101 Protoplasm 46 Proximate principles— Table of 110 Prussic Acid 62 Pole drains : 128 R. Reproduction— Proper age for in ani- mals 168 Rock salt 25 Roots 34, 35,36,37, 40 Root caps 35, 152 Root hairs 39 Root pruning 43 Root development— When most active... 42 Roots and stems— Correspondence be- tween 42 s. Salt 19, 25, 100 Salt springs '25 Sand 23 Sap— Circulation of 53 ScheePs Green 31 Seeds— Temperature at which they ger- minate 141 Seeds and grains 154 Silicon 23 Silica 23 Silver 23 Spongeoles 35 Soda 25,100 Soda— Nitrate of 25, 100 Soda— Bicarbonate of 26 Sodium 25 Sodium— Chloride of 25 Soil f ertilizatoin 72 Soil water 22 Soil exhaustion 93 Soils— their relation to vegetation 72 Soils— Sedentary 83 Soils — Transported 83 Soils— Drift 83 Soils— Alluvial 84 Soils— Colluvial 84 Soils — Classification of 84 Soils— Clay 85 Soils— Color and texture of 86 Soils— Capacity for heat 141 Stamens 51 Starch 58,59 Steel 30 Stems 43 Stigma 52 Style 52 Straw 153 Sugars 59 Sugar- Cane / 69 Sugar— Grape 60 Sugar— Fruit 60 Sugar— Milk 60 Sugar of Lead 33 Sulphur 19 Sulphuric Acid 20 Sulphate of Lime 20 Sulphate of Magnesia 20 Sulphate of Soda 20, 26 Sulphate of Ammonia 20 Sulphate of Potash 20 Sulphate of Iron 31 Superphosphate of Lime 22 Symbols— Chemical 6, 7 T. Table for calculating the exhaustion and enriching of soils 152 Tables of weights and measures 167 Tanic Acid 62 Tartaric Acid 61 Tiles 133 Tin 33 Tobacco 89 Tree Rock 23 V. Vegetable acids 61 Vegetable fibrin 64 Vegetable casiene 61 Verdigris 32 Vinegar 62 Vitriol— Oil of 20 Vitriols 20 w. Water 11 Water— in fresh plants 54 Water— in air dry plants 54 Welding 30 Weights and Measures 167 Wheat 89,95 Z. Zinc 34 Zoology 5 BERKELEY LIBRARY *Ptf 6 raw 15m-l2,*24