One Thousand Questions in California Agriculture Answered Part 45

What is Intensive Cultivation?

From whom can I receive instruction or information regarding intensive cultivation?

Intensive cultivation has, so far as we know, not been made the subject of any treatise or publication. Intensive cultivation means the use of a maximum amount of labor, fertilizers and water for products of high market value. There is no better example of intensive cultivation in the world than is afforded by the practice of the best market gardeners and producers of small fruit. Next to them, on larger areas, would be the policies and methods of the fruit growers of California. Intensive culture, then, is not a particular method or system, but consists in doing the best thing for maximum production of any product which is valuable enough to spend the large outlay which is required. Just how this cultivation should be done depends upon the nature of the product and the conditions of soil and climate in whatever locality intensive cultivation may be undertaken.

Can a Man Farm?

Is it possible for a man with a few acres well cared for and carefully tilled to make a living and pay out on a purchase of land at $123 per acre? Could a good carpenter make wages and take care of a small tract for a year or so until well under way?

We consider $125 per acre for good land with a good water right a fair price. Financing a farming operation depends more upon the man than upon the good land. There are men who would, by intensive cultivation of salable stuff and right use of water, pay off the full value of the land from its produce in a couple of years. Others will never pay off. Of course, the nearer you can come to paying for the land at the beginning, and the more money you have for improvements, the more satisfactory your situation should be in every respect. There is a good chance for carpenter work in colony development, and considerable self-help could be secured in that way. You do not say whether you know anything about farming. Farming is a very complicated business and a basic knowledge derived from experience is a proper foundation to build upon in the light of the fuller application of scientific principles.

Soil Depth for Citrus Trees.

I have a top soil of rich loam containing small rocks and pebbles.

Underneath it is washed gravel, rocks, boulders, yellow sand, etc. What is the limit as to thinness before trees will not grow, or thrive?

Orange trees are growing quite successfully on shallow soil overlying clay where the use of water and fertilizers was carefully adjusted so as to keep the trees supplied with just the right amount. Under such conditions a good growth may be expected so long as this treatment is maintained. There should be, however, not less than three feet of good soil to make the large expenditure necessary to establish an orange orchard permanently productive, and all the depth you can get beyond three feet is desirable. We question the desirability of planting orange trees even on a good soil overlying gravel, rocks or sand. Roots will penetrate such material only a short distance usually. It is almost impossible with such a leachy foundation to keep the surface soil properly moistened and enriched; You are apt to lose both water and fertilizer into the too rapid drainage.

Soils and Oranges.

I find this entire district underlaid with hardpan at various depths, from 1 to 6 feet down, and of various thicknesses. This hardpan is more or less porous and seeps up water to some extent, but is too hard for roots to penetrate. It is represented to me that if this hard pan is down from 4 to 5 feet it does not interfere with the growth of the orange tree or its producing. Is 4 or 5 feet of the loam enough?

Four or five feet of good soil over a hardpan, which was somewhat porous, is likely to be satisfactory for orange planting. There has been trouble from hardpan too near the surface and from the occurrence of a hardpan too rich in lime, which has resulted in yellow leaf and other manifestations of unthrift in the tree. Discussion of this subject is given on page 434 of the fifth edition of our book on "California Fruits," where we especially commend a good depth of "strong, free loam." This does not mean necessarily deep. The orange likes rather a heavier soil, while a deep sandy loam is preferred by some other fruits.

If you keep the moisture supply regular and right and feed the plant with fertilizers, as may be required, the soil you mention is of sufficient depth - if it is otherwise satisfactory.

Oranges Over High Ground Water.

Does California experience show that citrus trees can be grown upon land successfully where the water-level is 6 feet from the surface; that is, where water is found at that level at all seasons and does not appear to rise higher during the rainy season?

We do not know of citrus trees in California with ground-water permanently at six feet below the surface. If the soil should be a free loam and the capillarity therefore somewhat reduced, orange trees would probably be permanently productive. If the soil were very heavy, capillary rise might be too energetic and saturate the soil for some distance above the water-level. In a free soil without this danger the roots could approach the water as they find it desirable and be permanently supplied. Orange trees are largely dependent upon a shallow root system, the chief roots generally occupying the first four feet below the surface. From this fact we conclude that deep rooting is not necessary to the orange, although unquestionably deep rooting and deep penetration for water are desirable as allowing the tree to draw upon a much greater soil ma.s.s and therefore be less dependent upon frequent irrigations and fertilizations.

Depth of Ground-Water.

Is there probable harm from water standing 12 feet from the surface in an orchard? Also probable age of trees before any effect of said water would be felt by them? The soil is almost entirely chocolate dry bog. - W. E. Wahtoke.

Water at twelve feet from the surface is desirable, and water at that point will be indefinitely desirable for the growing of fruit trees. Of course, conditions would change rapidly as standing water might approach more nearly to the surface, a condition which has to be carefully guarded against in irrigation. But it can come nearer than twelve feet without danger.

Summer Fallow and Summer Cropping.

I own some hill land which has been run down by continuous hay cropping.

I am told that a portion must be summer-fallowed each year, but I wish to grow some summer crop on this fallow ground that will both enrich the soil and at the same time furnish good milk-producing feed for cows - thoroughly cultivating it between the rows. What crop would be best? I am told the common Kaffir or Egyptian corn are both soil enriching and milk producing.

If you grow a summer crop on the summer-fallowed upland, you lose the chief advantage of summer fallowing, which is the storing of moisture for the following year's crop. A cultivated crop would waste less moisture than a broadcast crop, surely, but on uplands without irrigation it would take out all the moisture available and not act in the line of a summer fallow.

Kaffir corn is not soil enriching. It has no such character. It probably depletes the soil just as much as an ordinary corn or hay crop. It is a good food to continue a milking period into the dry season, but you must be careful not to allow your cattle to get too much green sorghum, for it sometimes produces fatal results. We do not know anything which you can grow during the summer without irrigation which would contribute to the fertility of your land. If you had water and could grow clover or some legume during the summer season, the desired effect on the soil would be secured.

Soils and Crop Changes.

Peas and sweet peas do not grow well continuously in the same ground. I know this practically in my experience, but in no book have I ever found why they do not grow.

There are two very good reasons why some cla.s.ses of plants cannot be well grown continuously in the same piece of ground. One is the depletion of available plant food, the other the formation of injurious compounds by the plants, or the gradual increase of fungoid, bacterial or animate pests in the soil, which finally become abundant enough to seriously hinder growth. Different plants take the plant foods, as nitrogen, lime, potash, phosphates, etc., in different proportion. More important, perhaps, is the fact that the root acids that extract these foods are of different types and strength. Thus before many seasons it may happen that most of the plant food of one or more kinds may be nearly exhausted as far as that kind of plant is concerned that has grown there continually, while there would be plenty of easily available food for plants with a different kind of root system and different root acids, etc. This is one reason why rotation of crops is so good; it gives a combination of root acids and root systems to the soil during a term of years, and it also frees the soil from one certain kind of organism because it cannot survive the absence of the particular plants on which it thrives.

Summer-Fallow Before Fruit Planting.

I recently bought a ranch at Sheridan, Placer county, and was intending to put 10 acres to peaches and 50 acres to wheat or barley, but the residents tell me that the land must be summer-fallowed before I can do anything. The soil is a red loam and has not been plowed for six years.

Your local advisers are probably right as to the necessity for summer-fallowing in order to conserve moisture from a previous year's rainfall and to get the land otherwise into good condition. There might be such a generous rainfall that an excellent crop might come without summer-fallowing, and the results will depend upon the rainfall. If it should be small in amount, you might not recover your seed. By the same sign you might not get much growth on your fruit trees, but you could help them by constant cultivation and by using the water-wagon if the season should be very dry. Therefore, you are likely to do better with trees than with grain without summer-fallowing, although even for trees it is a decided advantage to have more moisture stored in the subsoil and the surface soil pulverized by more tillage.

Defects in Soil Moisture.