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Benefits of Tillage.
which is sought. For practical purposes, however, it is unnecessary to keep this distinction in mind, and we may classify the benefits of tillage under three general heads, arranging them approximately in their order of importance to the fruit-grower :
1. Tillage improves the physical condition of the land,
(a) By fining the soil, and thereby presenting greater feeding surface to the roots;
(b) By increasing the depth of the soil, and thereby giving a greater foraging and roothold area to the plant;
(c) By warming and drying the soil in spring;
(d) By reducing the extremes of temperature and moisture.
2. Tillage may save moisture,
(e) By increasing the water-holding capacity of the soil;
(f) By checking evaporation.
3. Tillage may augment chemical activities,
(i) By hastening the decomposition of organic
(j) By extending these agencies (g, h, i) to greater depths of the soil.
The simple statements of these offices of tillage is sufficient for the present occasion, except, perhaps, in respect to the improving of the texture of the
soil and the conservation of the moisture, for if the cultivator is skilled in these latter matters, all the other benefits will follow.
The texture of the soil.-The texture or physical condition of the soil is nearly always more important than its mere richness in plant-food. That is, the productivity of land is not determined wholly, and perhaps not even chiefly, by the amount of fertilizing elements which it contains. This is particularly true of all lands-like the clays-which tend to become and to remain hard and unpleasant if left to themselves. Plant-food is of no consequence unless the plant can use it. The hardest rocks may contain various plant-foods in abundance, and yet plants cannot grow on them. A stick of wood contains potassium and phosphorus and nitrogen, and yet nothing grows upon it until it begins to decay. A hundred pounds of potash in a stone-hard lump is worth less to a given plant than an ounce in a state of fine division. Soils which the chemist may pronounce rich in plant-foods may grow poor crops. In other words, the chemist can not tell what a soil will produce; he can only tell what it contains.
All this is not surprising, when we come to think of it. Every good farmer knows that a hard and lumpy soil will not grow good crops, no matter how much plant-food it may contain. A clay soil which has been producing good crops for any number of years may be so seriously injured by one injudi
*See, for example, Bull. 119, Cornell Exp. Sta.
Fertilizers vs. Tillage.
cious plowing in a wet time as to ruin it for the growing of crops for two or three years. The injury lies in the modification of its physical texture, not in the lessening of its fertility. A sandy soil may also be seriously impaired for the growing of any crop if the humus, or decaying organic matter, is allowed to burn out of it. It then becomes leachy, it quickly loses its moisture, and it becomes excessively hot in bright, sunny weather. Similar remarks may be applied to all soils, although they are not equally true of all.
If these remarks are true, then it follows that it is useless to apply commercial fertilizers to lands which are not in proper physical condition for the very best growth of crops. If potash, for example, were applied to hard lumps of clay, it could not be expected to aid in the growth of plants, because plants cannot grow on such a place. If the same quantity were applied to mellow soil, however, the greater part of it would be presented to the roots of plants at once, and its effects would no doubt be apparent in the season's crop. The improvement of the texture of the soil is not only a means of presenting the plant-foods to the roots of plants and of uniformly distributing what fertilizer may be applied, but it is also a direct means of conserving moisture and of hastening chemical activities.
The soil is a vast storehouse of plant-food, and the first effort of the husbandman should be to make this store available to plants. "Men take him for a foole or a mad man that, having store of
wealth in his trunck, doth yet complain of want. What though the key be rusty for want of use? tis easier to get that scoured, then to obtaine such another treasure. And surely I may upon most sure grounds say, that our Native Countrey, hath in its bowels an (even almost) infinite, and inexhaustible treasure; much of which hath long laine hid, and is but new begun to be discovered. It may seem a large boast or meer Hyperbole to say, we enjoy not, know not, use not, the one tenth part of that plenty or wealth & happinesse, that our Earth can, and (Ingenuity and Industry well encouraged) will (by Gods blessing) yield."*
The moisture of the soil.-Lands oftener need moisture in the growing season than they need fertilizers. The fact is that they generally need both, if the largest and best crops are to be secured. Drought seems to most people to be one of those calamities in which there are no secondary or incidental blessings, and it must be confessed that the lesson of the recurring droughts has not yet been learned by the great body of farmers. remedy which occurs to most persons is irrigation, and yet there is sufficient rainfall in most parts of the fruit-growing regions of the country to provide all the needs of large crops. The difficulties are that this rainfall comes when it seems not to be wanted, and very much of it is allowed to escape by evaporation. The truth is that the heavy rainfall
*Samuel Hartlib, "An Essay for Advancement of Husbandry-Learning, London, 1651, p. 3.
Saving the Water.
usually comes at the best season, for it is the period of inactivity, when the work of the farmer and the growth of the plants are least interfered with. If we, in the east and south, were perfectly certain that we should have no rain from June until September, we should carefully husband the rainfall of the earlier months, and we should suffer little loss; but now that we expect rain all summer long, we neglect the saving of the early rains, and gamble upon the chance of having a rain when we shall need it. It often happens that the dry countries suffer least for water!
How shall we save the water? By holding it in the earth. If the earth is finely divided and yet compact, the capillary pores or interstices will hold enormous quantities of water. If, then, we break
up these interstices next the atmosphere, we shall prevent the water from passing off by evaporation. The whole subject of the saving of moisture, therefore, falls into two means, the catching and holding of it (or the making of a reservoir), and the prevention of evaporation. It is, therefore, a question of plowing and then of surface tilling. It will thus be seen how futile it may be to try to save the water by beginning tillage late in the season, when a drought is threatened. If the land has not been well prepared, there may be no water to save by that time. It may either have run through the land into the drains, or it may have evaporated long before the farmer saw the need of saving it.
The hard-pan may be so near the surface that but