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 diflBcult 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 



