13 
Cleaned, Treated and Tested Seed 
II. HOME METHODS OF SEED TESTING. 
The Purity Test.—Purity tests are beneficial and advisable from 
the standpoint of better yields made possible by definite knowledge of 
the quality and constituents' of the lot of seed to be sown. Casual in¬ 
spection of a lot of seed will reveal very few of the weed seeds present, 
especially when the lot under examination has been milled and the 
chaff, sticks, and smaller weed seeds removed. A carefully conducted 
purity test will, because of its thoroughness, result in the detection of 
all adulterants as well as unmilled weed seeds and inert matter. Take, 
for example, alfalfa containing a small amount of large-seeded alfalfa 
dodder. Not one buyer in ten will detect this undesirable seed because 
of its close resemblance in size and color to the alfalfa seed. 
Each farmer before planting should know just what his lot of 
seed contains of weed seeds and inert matter such as broken seed, chaff 
and dirt. 
When seed is home-grown there is no particular hurry about hav¬ 
ing a purity test made, and there is ample time to have tests of such 
seeds made at the Colorado Seed Laboratory, which is specially 
equipped to make very accurate analyses. When it is necessary to 
purchase seed from a seed company it may be advisable to make a 
purity test at home, for a home test means immediate returns and the 
farmer is able to take advantage of a choice lot of seed when it ap¬ 
pears on the market, whereas a delay of several days in securing re¬ 
sults from the state laboratory would mean loss of opportunity in se¬ 
curing the best seed before the stock has been entirely exhausted. The 
prospective buyer should ask for a representative sample of the seed 
offered for sale and satisfy himself as to the quality before purchas¬ 
ing. The large and reputable seed companies conduct a ‘‘buy on 
sample” business, and a purity test is therefore entirely possible. 
Fig. 1. —Seed trier which may be used in taking samples of the smaller seeds from 
sacks without opening the sacks. 
Samples from home-threshed seed should be taken in such a way 
as to secure a representative sample. The ordinary metal seed sam¬ 
pler (Fig. 1) is very commonly used for sampling small seeds such as 
alfalfa, red clover and timothy in bags. The use of this sampler does 
away with opening each bag. When only one bag is to be sampled, 
small amounts should be taken from the top, middle and bottom of the 
sack. If more than five bags, samples should be taken from every fifth 
bag. The composite sample of one lot in any case should be thor¬ 
oughly mixed in a receptacle so that there may be even distribution of 
weeds and dirt throughout the sample. The sample so mixed is known 
