GREEN MANURES AND COVER CROPS 
55 
clover, and it is, therefore, more highly valued by some 
as a quick manurial crop. It should be sown at the same 
time as red clover. 
g5. Crimson clover. — As a cover crop crimson clover 
is used to a considerable extent in the middle Atlantic 
seaboard region. It is valued highly for its power to 
assimilate free nitrogen. A crop cut May 22 at the Dela- 
ware station (Delaware Station Bui. 60, p. 10) contained 
180 pounds of nitrogen to the acre. The plant thrives 
best in sandy soils and where the winters are not too 
severe. It is unquestionably the most valuable manurial 
crop in the trucking sections of New Jersey. 
The seed should be sown not later than August. July 
is not too early for the cooler sections. A common prac- 
tice is to sow before the last cultivation of tomatoes, 
sweet corn and other late truck. Crops are sometimes 
harvested and the ground thoroughly harrowed before 
sowing crimson clover, while plowing before harrowing 
and sowing is often desirable. The seed soon loses its 
vitality and, therefore, only fresh seed should be sown. 
Not less than 15 pounds an acre should be used. The 
Virginia Truck Experiment Station claims that not less 
than 20 pounds an acre should be used at Norfolk. 
97. Rye, while a nonlegume, is exceedingly valuable 
under certain conditions. It grows fairly well in any 
soil. This cannot be said of most cover crops. Because 
of this fact it is often possible to start with rye on very 
poor soils and then use more desirable crops after some 
humus has been added to the soil. Rye may be sown 
later in the fall than any other crop, and for this reason 
it is a valuable crop to start after the removal of late 
vegetables, when it would be useless to sow any of the 
legumes. It thrives throughout the North and is widely 
regarded as the best general purpose cover crop for cold 
sections. To secure a good stand not less than three 
bushels of seed should be used to the acre. 
