SOILS AND FERTILIZERS
~Soils Needed for Good Growth~—The nut trees adapt themselves to a very wide range of soil conditions. In fact, few other trees are capable of such a wide range of adaptability to soil types. The uplands usually planted to corn and wheat and the flood plains of the river basins may both be well suited to nut growing.
For good growth and production deep well-drained soils are required. Under proper conditions the trees develop rapidly, have an extensive root system, and eventually may reach a great age. Furthermore, nut trees cannot grow successfully on wet poorly-drained land where water stands on or just beneath the surface a considerable portion of the year. Lowlands which may be found well adapted to the growth of willow and gum trees, may be too wet and sour for the growth of nut trees. It would also be well to avoid dry, very thin, and very sandy soils.
In their native range the pecan, hickory, and walnut thrive on the alluvial soils of the Missouri and Mississippi River Valleys. They grow well also on the upland sandy loam soils adapted to the growth of corn, oats, and wheat. All of these nut trees are usually influenced more by the fertility, humus, and moisture content of the soil, than by any particular soil type.
~Fertilizers for Nut Trees~—The deep rich alluvial soils of river and creek valleys do not present the same fertilizer problems as light and heavy upland soils. Manure supplemented with superphosphate at the rate of about 20 to 30 pounds to a ton should prove to be a satisfactory fertilizer on depleted soils. It is spread in a circle around the trees extending out about twice the spread of the branches and plowed or harrowed into the soil. A moderate application would range from 8 to 12 tons to the acre.
Leguminous cover crops are particularly valuable for building up the nitrogen and humus content of the soil when plowed under. Their judicious use with non-leguminous cover crops and supplemented with commercial fertilizers to increase the tonnage for plowing under, will usually bring good returns in growth and production.