l; but it is more economical to plant the
orchard on good soil than to attempt the improvement of a poor soil.

6. A short, non-legume sod rotation is an efficient means of building up
a depleted orchard soil. After a sod of any kind becomes thick tree
growth is checked and yields decline. Orchard sods should be turned
under or partially broken, frequently.

7. Moisture conditions often are more favorable in the sod orchard than
in the cultivated orchard. Runoff is checked by a sod and less water
is used by a sod in mid-summer, after it has been mowed, than by a heavy
cover crop.

8. Under a non-legume sod the soil nitrate supply becomes very low in
late May or early June, necessitating early applications of nitrogenous
fertilizers. Annual applications of 10 pounds of nitrate of soda per
tree, or its equivalent in sulphate of ammonia or other forms, have
proved profitable in this orchard. Superphosphate, in light
applications, has increased sod and cover crop growth.

9. Trees receiving annual tillage with July seeding of cover crops have
not done as well as those under sod rotations. If the cover crops are
seeded in early June, as has been practiced since 1929, the difference
may not be marked.

10. To maintain equal yields, Stayman and Baldwin must make longer
branch growth than York.

In addition to these conclusions I will say that any grower who will
keep his orchard soil in a state of fertility (by use of manure, proper
farm crop fertilizers--nitrate, phosphate or potash alone or in
combination with each other--liming and, if necessary, drainage) which
will permit growing clovers, alfalfa, soy beans, cow peas, vetch, or any
of the legumes, and who really does grow them as covers in his grove or
orchard, turning them back into the soil with a minimum period of spring
cultivation--just enough to prepare a seed bed--will never need to worry
about his soil fertility or water holding capacity.

You note that I say a minimum of cultivation. We taught twenty years
ago that cultivation should continue during June, July, and August. We
now feel that this teaching was wrong. We can see no benefit from this
long summer cultivation but do see some harm. Cultivation during the hot
weather of June, July, and August will only aid in burning out the
organic matter in the soil, just the very thing we plant a cover for.
Many of the covers such as alfalfa, sweet clover and non-legume grasses
can be harrowed very heavily in e