748 IOWA DEPARTMENT OF AGRICULTURE 



ing catchfly, pennycress, field peppergrass, two kinds of false flax and black 

 mustard, English charlock, Indian mustard, wild carrot, field bindweed, 

 clover dodder, field dodder, corn gromwell, rattail plantain, buckhoim, 

 ragweed, wild sunflower, oxeye daisy, Canada thistle, bull thistle, wild 

 chicory. 



Other weed seeds commonly found in red clover include: Crab-grass, 

 witch-grass, yellow foxtail, green foxtail, velvet grass, sedge, sorrel, 

 knotweed, pale knotweed, lady's-thumb, larnb's-quarters, rough amaranth, 

 spreading amaranth, wild spurry, two kinds of chickweed, mouseear 

 chickweed, forked catchfly, creeping buttercup, peppergrass, shepherd's 

 purse, cinquefoil, hop clover, yellow trefoil, bird's-foot trefoil, wild gera- 

 niums, stork's-bill, spurge, spiny sida, evening primrose, red pimpernel, 

 sticktight, forget-me-not, three kinds of vervain, catmint, healall, rough- 

 leaved toadflax, smaller broad-leaved plantain, bracted plantain, field mad- 

 der, cleavers, wild corn salad, black-eyed Susan, dog fennel, field camo- 

 mile, scentless camomile, cat's-ear, oxtongue, hawkweed picris. 



The American or the Canadian origin of red clover seed is strongly 

 indicated by the presence of the following weed seeds: Night-flowering 

 catchfly, field dodder, rat-tail plantain, ragweed, bull thistle, witch-grass, 

 lady's-thumb, spreading amaranth, peppergrass, cinquefoil, spurge, spiny 

 sida, bracted plantain. Seeds of Canada thistle or of small-fruited false 

 flax, if found in abundance, indicate that the source of the seed is 

 Canadian. 



European origin of red clover seed is indicated by the presence of 

 certain weed seeds, and the occurrence of several kinds of these in the 

 same sample (especially in the absence of the kinds heretofore mentioned 

 as occurring in American-grown seed), lends weight to the probability 

 of European origin, as follows: Clover dodder, wild chicory, wild spurry, 

 chickweed, forked catchfly, bird's-foot trefoil, wild geraniums, red pimper- 

 nel, forget-me-not, vervain, field-madder, wild corn salad, scentless cam- 

 omile, oxtongue, hawkweed picris. The presence of a considerable quan- 

 tity of distinctly small-seeded red clover seed further indicates Eureopean 

 origin. 



TESTING ALSIKE CLOVER SEED. 



Alsike clover seed is distinguished from other kinds by its dark-green 

 color, the small size, and the heart-shaped oval form of individual seeds. 

 The lighter colored seeds are often mottled. Old seed is distinguished 

 from new by the dull, reddish-brown color it acquires. 



White clover seed often appearing in alsike seed is distinguished by 

 its yellowish or pinkish color. 



Yellow trefoil seed, sometimes used as an adulterant and often present 

 as an incidental impurity, is coarser than the alsike seed and is further 

 distinguishable by its greenish-yellow or brown color and the character- 

 istic form of individual seeds. Adulterants used other than trefoil seed 

 are old alsike seed, timothy seed, and weedy screenings. 



Germination proceeds between the second and sixth days of the test, 

 and the viability often attains 99 per cent. Hard seed is less frequently 

 observed in alsike seed than in red slover. The purity commonly amounts 

 to 98 or 99 per cent. 



