Testing Farm Seeds. 



377 







the kinds given in the following list affords strong indication of domestic 



production. 



The weed seeds especially suggestive of European production include: 

 (Fig. 19) chickweed (q), forked catchfly (t); (fig. 20) creeping buttercup (a), 

 bird's-foot trefoil (g), wild geraniums (h, i and j), red pimpernel (o), forget- 

 me-not (q), vervain (r); (fig. 21) rough-leaved toadflax (c), held madder (g), 

 wild corn salad (i and j), scentless camomile (o), hawkweed picris (s). The 

 presence of white seeds of crimson clover is an additional indication of Euro- 

 pean production. 



TESTING ALFALFA SEED. 



Alfalfa seed is distinguishable from the clover seeds by the some- 

 what variable kidney-shaped form of individual seeds (figs. 2, 4, 5, 6 and 

 26) and by the greenish-yellow or light-brown color. Old, poorly de- 

 veloped and shriveled seeds have a dull, reddish-brown color. In general 

 the details of testing red clover seed (p. 33) may be followed in testing 

 alfalfa. 



Alfalfa seed is adulter- 

 ated by the use of (1) yel- 

 low trefoil (figs. 4 and 23), 

 (2) sweet clover (figs. 5 

 and 27), (3) bur clover 

 (fig. 6), (4) light, shriv- 

 eled alfalfa screenings or 

 low-grade, weedy seed. 



Besides giving especial 

 attention to the matter of 

 adulteration, the question 

 of domestic or of Europe- 

 an production should be considered in making the purity test. Much of 

 the seed on the market is imported, and the question of domestic or for- 

 eign production often can be determined by the weed seeds present. 



The purity should attain 98 or 99 per cent, the viability 97 to 99 per 

 cent. The germination test should be completed in six days, most of the 

 seeds sprouting during the second and third days. Considerable hard 

 seed is often found in new seed. 



The noxious weed seeds found in alfalfa seed include: (Fig. 17) sand bur 

 (a), wild oat (b), chess (c), quack-grass (e), dock (f), black bindweed (g), 

 Russian thistle (h), corn cockle (i), white campion (j), bladder campion (k), 

 night-flowering catchfly (1), cow cockle (m), pennycress (n), field peppergrass 

 (o), false flax (p and q), black mustard (s), English charlock (t) ; (fig. 18) 

 Indian mustard (a), hare's-ear mustard (b), tumbling mustard (c), wild carrot 

 (d). field bindweed (e), clover dodder (g), small-seeded alfalfa dodder (h), 

 field dodder (i), large-seeded alfalfa dodder (j), corn gromwell (k), rat-tail 

 plantain (1), buckhorn (m), ragweed (n), gumweed (o), wild sunflower (p), 

 oxeye daisy (q), Canada thistle (r), bull thistle (s), wild chicory (t). 



Fig. 26. — Seeds of alfalfa: a, Individual seeds, 

 showing variation in form ; b, edge view of a 

 seed, showing the scar ; c, natural size of 

 seeds. 



