Production of Sugar-Beet Seed 227 
order that the soil may be firmed around the roots and 
also to insure an early starting of growth. Two or three 
additional irrigations are usually ample to mature the 
seed crop. The soil should have sufficient moisture while 
the seed is forming. Early cultivation is desirable to 
keep weeds in check as they are much more easily killed 
at this time. After the seed-stalks become too large, it 
is difficult to get through the field with a cultivator; un- 
less weeds have been kept in check up to this time, they 
May prove troublesome and may need to be removed by 
hand. In any case, late hoeing may be desirable. 
Harvesting and threshing. (Plate XXVI.) 
Since the seed does not ripen evenly, it is necessary to 
go over the field and cut some of the plants before all are 
ripe. This is not practical when seed is raised on a large 
scale. The ripening period may extend over a number of 
weeks. The cutting is done with a sickle and the seed- 
stalks piled in the field to dry before threshing. It 
usually pays to go over the field after harvest with a brush 
and dustpan to glean seed that has fallen to the ground in 
cutting. Threshing can be performed with an ordinary 
grain thresher with the speed retarded, special screens, 
and certain adjustments. Special threshers may also be 
procured. From fifteen to twenty tons of seed can be 
threshed in a day. 
After the seed is threshed, some dirt and stems always 
remain. These are best removed by running the seed 
over a revolving canvas, which allows the seed to roll off 
and at the same time carries the stems away. The dirt 
and chaff are removed with a fanning mill before the seed 
