locusts, all of which are known to improve the pasture grasses to some
extent. The potential income which may be derived from such plantings
over this vast acreage is enormous and is the more striking in that
these pasture trees occupy a plane that is now idle and unproductive,
that is, the area lying above the grass tops. The nuts produced on this
"upper story" will represent almost all "clear profit" in that very
little care need be given these walnut trees after they have been
properly planted. Livestock guards will need to be placed about the
trees at planting time and kept there until the trees have grown to the
point where they may no longer be harmed by straddling and browsing.

Pastures are excellent sites from another angle. The closely grazed sod
furnishes an ideal place to rake the nuts together at harvest time.
Anyone who has hunted for nuts in a dense ground cover will appreciate
this factor.

While the walnut responds best to the deep, fertile soil of the river
bottoms and flood plains, it will grow well on the lower portions of
slopes if water is available and the site is not too exposed to the
force of drying winds. Contour strips should be prepared by plowing
several furrows downhill, each a little less in depth than the
preceding, and the walnuts planted thereon. The walnut is a spreading
tree and plenty of space should be allowed. Perhaps it may be wise to
plant the walnuts at extended intervals and fill up the contour row with
black locusts, for post wood, and honey locusts to produce succulent
pods for cattle feed. In any event, it is better to allow too much,
rather than too little space, as walnuts are long-lived trees and will
thrive best where there is least competition. In Iowa, black walnuts are
responding well to "basin culture" in sites which were prepared by
"scalping" the sod from the upper portion of a slope and depositing it
on a lower portion in order to catch and retain more water.

Nut trees are like all other trees in that they react favorably to good
horticultural practice. Fertilizer, particularly nitrogen, is usually
always helpful. The addition of lime when the soil is acid and of
organic matter when humus becomes depleted will aid in better soil
aeration and an increased moisture supply. This, in turn, will be
reflected in more vigorous tree growth and greater nut production.
Occasional spraying may be necessary to control the Datana caterpillar
in the summer.

Chinese chest