1909.] PUBLIC DOCUMENT — No. 31. 55 



lu the coming year we expect to give this problem further con- 

 sideratiou. 



Onion and tobacco seed constitute the bulk of the seed re- 

 ceived for separation. Both of these crops are grown extensively 

 in the Connecticut valley. The object of separation is, of course, 

 to discard the small seed and chaff, leaving only the large and 

 heavy seed for planting. The percentage of the seed discarded 

 varies somewhat. This would naturally be expected, as the seed 

 comes from different dealers and varies in size and quality, al- 

 though much of the tobacco seed is home grown. 



In some of our seed separation work the amount discarded 

 depends upon the percentage of germination of the sample. 

 Certain growers make a practice, before purchasing in bulk, 

 of obtaining samples, which are sent to the experiment station 

 for testing. A certain percentage of the small seed is blown 

 out, and the original sample, as well as the large and small 

 seed are tested for germination. The results are then sent to 

 the grower, and if satisfactory he purchases in bulk and requests 

 that a certain percentage be blown out. 



Small seeds, like tobacco, which are received in small quan- 

 tities, are sej^arated in glass tubes with bulbs of a special form, 

 and in this form of separation, which is fully described in Bul- 

 letin No. 121 of this station, we make use of fifteen pounds' air 

 pressure. The larger seeds, like onion, are separated by a spe- 

 cial winnowing machine, given a constant speed by an electric 

 motor. The machine is so arranged that a bushel or more may 

 be separated at one time. 



Careful germination tests were made again this year to prove 

 the value of seed separation, and experiments in planting the 

 different grades of separated seed were also made in co-opera- 

 tion with growers in different parts of the State. 



The following tables give an outline of the seed work which 

 has been done the past year : — 



