10 SEPARATING BUCKHOBN FROM CLOVER AND ALFALFA SEEDS. 
of an inch in diameter. If the seeds are thus divided into two grades 
very few clover or alfalfa seeds will he carried over with the 1 nick- 
horn seeds. The old methods cause a good deal of waste in this 
respect. 
THE KIND OF SAWDUST TO USE. 
Sawdust from any kind of wood may he used. Some of that used 
by the writer was mixed sawdust from a carpenter shop and some 
was from a planing mill. All sawdust too coarse to pa<> through 
a Xo. 22 mesh should he discarded, a- well as that fine enough to pass 
through a Xo. 36 mesh (fig. 8). 
Fig. 8. — Mixed sawdust passed through a No. 22 mesh (a) ; sawdust of same grade as 
a but with fine particles (c) sifted out through a No. :\C> mesh (6) (the grade which 
should be used) ; fine sawdust sifted from h ; too fine sawdust (c). (Natural size i 
Mr. C. V. Piper, of the Bureau of Plant Industry, suggested the 
use of the chaff of various grasses, such as fescue and redtop. as being 
exceedingly light, absorbent, and of the proper size. Thi- was tried 
and found exceedingly successful. Whenever available it may be 
used in preference to sawdust (fig. 9). The chaff should be used 
in exactly the same manner and proportion as the sawdust. 
DRY SAND OR ROAD-DUST METHOD. 
This method is not considered quite as good as the preceding. 
Road dust and sand are not nearly as absorbent as the materials just 
discussed; consequently, a larger proportion of them must be used. 
say. about one part of seeds to eight of sand or dust. Furthermore, 
being so much heavier than sawdust or chaff these materials entail 
more labor. However, the same method is applicable to them. All 
sand or dust too coarse to pass through a Xo. 36 mesh should be dis- 
carded, as well as that which is so fine as to pass through a No. 50 
mesh (see i\<x. 4. d). 
[Circ. 2 1 
