A Cover Crop Program for Florida Pecan Orchards


where winter and summer legumes were grown each year. Third,
a combination of oats and Crotalaria spectabilis grown during
winter and summer, respectively, did not produce profitable nut
yields, either with or without annual applications of sulfate of
ammonia. Fourth, owing to habits of the pecan, several years
are required to revive weak trees to a point where twig growth
will be sufficient to produce profitable nut yields. Fifth, pecan
varieties vary in their productive ability and therefore it would
be possible to produce profitable returns with a suitable variety
while one unadapted would show a loss.

 SUMMARY
 An experiment to test the effects of cover crops on growth
and yield of Frotscher and Stuart pecan trees on Norfolk fine
sandy loam soil was conducted at Monticello from 1927 to 1934.
Legumes grown in winter and summer were compared with
combinations of non-legumes in winter and legumes in summer,
and with no planted cover crops. Superphosphate and sulfate
of potash were applied in the fall broadcast over the entire
experimental area when the seed were planted. Sulfate of am-
monia applications were made in the summer to half of each
plot to test its effect on growth and production of pecan trees
with and without the different cover crops.
 Cover crops of legumes in winter and summer caused signifi-
 cant increased production of pecans in the experiment. The
 combination of a non-legume in winter and legume in summer
 failed to prove satisfactory, and nut yields generally were lower
 than in the plot where no planted cover crops were grown.
 A nitrogenous fertilizer, sulfate of ammonia, applied during '
 the summer generally caused higher nut production. The in-
 'creases, however, were significantly greater in the all-legume
 plots than with the other treatments.
 Frotscher trees responded better than Stuart and produced
 decidedly heavier crops of nuts. However, with both varieties
 there were no marked differences in yields until after cover
 crops had been annually returned to the soil for four years.
 An improvement in condition of the soil was obtained where
 legumes were grown. This was shown in increased nitrogen
 content and heavier growth of Sudan grass produced in the soil
 samples and in greatly increased nut production.