II. VARIETIES, CULTURE, AND FERTILIZATION OF COTTON ON PIEDMONT RED CLAY LOAM, RED CLAY AND VALLEY SOILS.

Seven years' fertilizer and variety experiments have been conducted on the red clay loam soil of the Iredell Test Farm. On basis of these results and other information which we have, the suggestions below are given for the culture and fertilization of cotton on the red clay loams, red clays, and valley soils of the Piedmont, and the varieties of cotton which are best suited to them.

Cotton is not a hard or exhaustive crop on the soil, when the soil and crop are handled with care and intelligence. A bale of cotton. (900 pounds of seed and 500 pounds of lint) removes from the soil in round numbers:

30 pounds Nitrogen,

12 pounds Phosphoric Acid, and
13 pounds Potash;

worth at present prices of fertilizer ingredients $7.20. Only 48 cents worth of this is carried away in the lint. The seed can be sold for enough to return in commercial fertilizer considerably more plant food than the lint and seed took from the soil. The stalks, leaves, and bolls, which should never be burned or otherwise. removed, and 95 per cent of which have come from the air, add vegetable matter or humus to the soil. If the land is liberally fertilized in the right way and protected from surface washing, it should continue to produce large and profitable crops of cotton from year to year, and with a good rotation and proper fertilization will increase in fertility and productiveness. None of our staple crops are as easy on the soil as cotton when handled in the way indicated above.

Preparation and Cultivation. The land should be thoroughly and well prepared by breaking in the fall or early spring to a depth of 6 or 8 inches, and the soil may be gradually deepened beyond this to advantage. Before planting, cut up well with a disk harrow to get rid of clods and to make a good seedbed and run off rows 311⁄2 to 4 feet apart and on very fertile land 42 feet. As a rule, the fertilizer should be put in the drill before planting and the cotton planted on a level or just above the level, according to the season and drainage condition of the land. Weeders and light harrows may be run across the rows two or three times before and after the cotton is up and before cultivation with cultivators and hoeing begins. When the crop is well up and danger of frost is over, hoe and thin to a

stand of 15 to 20 inches in the drill, leaving as nearly as possible one stalk in a place, and giving greater distance in the row and between rows as the productiveness of the land increases. On thin land the rows should be closer together and the cotton closer in rows, as the stalks do not grow very large; but distance should be given both ways as the land increases in productiveness, from whatever cause brought about. Cultivate with good one or two-horse cultivators, which will not require more than two furrows at greatest to the row, every ten days to two weeks and as nearly as possible after rains to keep down grass and weeds and to conserve the supply of moisture. The cultivation should be comparatively deep early in the season, becoming shallow as the crop grows and the root system develops. As the season in the Piedmont is short for cotton, it seems desirable not to continue the cultivation late on strong lands, as this will stop growth earlier and hasten maturity. On land producing strong growth it has been found to pay to top the cotton about September first, thus forcing the energies of the plant into development of fruit already set.

Varieties. In seven years sixty varieties of cotton have been tested on the Iredell Farm, a number of these running through the entire period. The earlier maturing varieties of the King type have given the largest returns, though now and then, with a long season, the large boll, late-maturing kinds have stood well. Cottons of this latter type have made large showy growth, but frost catches them too often to make them safe for that soil and section of the State. Among the varieties which have done well are

King's,
Simpkins',
Sugar Loaf,
Williams',

Edgeworth,

Webb,

Hodge,

Shine's Extra Early,
Dozier's.

These are all small to medium boll, early-maturing varieties, a number of them being of the same origin. Cleveland's Big Boll and Cook's Improved, among the medium and large boll kinds have done well.

The results of variety tests have been published each year and are summarized in the FEBRUARY (1909) BULLETIN. These results can be had for study by any one specially interested in them.

Fertilization.-Analyses of these soils show that they are very low in phosphoric acid, high in potash, and have a fair supply of lime, the quantity of nitrogen depending on the amount of vegetable or organic matter in the soil. Experiments show that phosphoric acid is the most needed constituent for the production of cotton, it having produced about two-thirds of the increased yield and profit, and nitrogen and potash combined about one-third. It is not possible, with present results, to say just what is the best proportion of these three constituents for most profitable returns, but it is certain that the fertilizer should carry a very high percentage of phosphoric acid and comparatively low percentages of nitrogen and potash. The indications are that a mixture containing 10 or more per cent phosphoric acid and 2 per cent each of nitrogen and potash will give close to if not the best returns. This mixture should be used for best results at the rate of at least 400 pounds per acre, and as much more as one can afford up to 1,000 pounds.

The nitrogen may be all derived from blood, tankage, cotton-seed meal, or similar products, or in part from one or all of these, and in part (up to one-half) from nitrate of soda or sulphate of ammonia.

Kainit, manure salt, sulphate or muriate of potash may furnish the potash, and acid phosphate the phosphoric acid. Four hundred pounds of the above mixture would contain 40 pounds phosphoric acid, and 8 pounds each of nitrogen and potash, and 1,000 pounds would contain 100 pounds phosphoric acid and 20 pounds each of nitrogen and potash. The required amounts of phosphoric acid in 400 and 1,000 pounds respectively of this mixture would be supplied by 286 and 715 pounds of 14 per cent acid phosphate; the nitrogen by 61%, and 154 pounds of 13 per cent dried blood, and the potash by 40 pounds and 100 pounds of 20 per cent manure salt. Other materials or other grades of these same materials may be used, and it will not be difficult, knowing just what they contain, to use such quantities of them as will be necessary to furnish the required amount of plant food, having in mind that it is the specific number of pounds of phosphoric acid, nitrogen, and potash that is desired, rather than a given weight of mixed fertilizer.

It is not more, but perhaps less difficult to calculate the number of pounds of nitrogen, phosphoric acid, and potash to be applied per acre to any given crop from materials which are to be had than to estimate the exact number of pounds of the materials to make a formula of a certain composition: as for example, in an 8-2-2 goods. The question of filler does not have to be considered in doing this. as is necessary in making a fertilizer formula in the usual way. When it is desired, for instance, to apply the equivalent of 400 pounds per acre of a fertilizer mixture containing 10 per cent of available phosphoric acid, and 2 per cent each of nitrogen and potash, or 40

210

BIENNIAL REPORT COMMISSIONER OF AGRICULTURE.

pounds of phosphoric acid and 8 pounds each of nitrogen and potash, it is only necessary to divide the number of pounds of plant food desired per acre (40, 8, and 8) by the percentage composition of the materials to be used, as follows:

The best and most economical way to apply this fertilizer is in the drill before planting, though there is no objection to dividing the application into two parts, putting one-half in the drill before planting and applying the other half as a side dressing around July first, according to season and growth of crop. It is certain that quantities of 400 pounds and less of fertilizer should not be applied broad

cast.

I. FERTILIZER EXPERIMENTS WITH CORN ON PIEDMONT RED

CLAY LOAM SOIL

AND

II. VARIETIES, CULTURE, AND FERTILIZATION OF CORN ON PIEDMONT RED CLAY LOAM, RED CLAY, AND VALLEY SOILS.

BEING A REPORT OF WORK WITH CORN ON THE IREDELL TEST FARM
IN 1903-'09, INCLUSIVE.

BY B. W. KILGORE, C. B. WILLIAMS, G. M. MACNIDER, AND F. T. MEACHAM.

GENERAL SUMMARY OF RESULTS OF FERTILIZER TESTS.

1. The right fertilization of corn has paid well on the red (cecil) clay loam soils of the State. What this fertilization should be on this and similar soils is shown by the results of our experiments as given on the following pages.

2. For the production of corn on this land nitrogen alone was used at a loss; potash alone was used at a loss; and from nitrogen and potash combined with each other the increased yields over unfertilized plats were very small and were not sufficient to cover the cost of fertilizer, the fertilizer application from these two constituents having cost $1.26 per acre more annually than the value of the increased yield of corn. This shows that neither nitrogen alone, potash alone, nor nitrogen and potash combined with each other should be used on this land in growing

corn.

3. Phosphoric acid alone produced increased yields at good profits in all cases. Nitrogen combined with phosphoric acid added decidedly to the increased yields and profits, as did potash also when combined with phosphoric acid, though larger yields were obtained from nitrogen and phosphoric acid than from potash and phosphoric acid, indicating that nitrogen is more important than potash for corn production on this soil. Nitrogen, phosphoric acid, and potash combined in a complete fertilizer gave slightly larger yields, but no larger profits than nitrogen and phosphoric acid and potash and phosphoric acid.