Fungous Diseasks oe Colorado Crop Plants 
23 
crushed in the thresher. A few broken smutted seeds can contam¬ 
inate a large amount of health)^' grain. Spores are carried from 
farm to farm by threshing machinery, and by wind. Bunt affects 
both spring and winter varieties of wheat. The spores of bunt 
will not cause smut in oats, barley, corn, or sorghum. The smuts 
of these cereals are distinct. 
Control .—The object of seed treatment is to kill all bunt spores 
clinging to the outside of healthy grains. Bunt spores are carried 
into the ground \^’ith the grain of wheat, the young seedling is in¬ 
fected and at maturity the heads of the plant are smutted. Before 
treating seeds with formalin, place them in a tub or barrel of cold 
water, and stir. The lighter smutted grains will come to the top 
and may be skimmed off. vSmutted seeds may also be fanned out 
with a good fanning mill. The easiest and most efficient seed treat¬ 
ment is the formalin sprinkle. This is done as follows: 
r I) Formalin is a solution of formaldehyde gas in water. It 
usually has a concentration of about 40 per cent. Ask for this 
strength. Formalin may be obtained of any druggist. Put i pint 
(i lb.) of formalin in 45 to 50 gallons of water. Stir thoroughly. 
Use this material when fresh; it deteriorates with standing. 
(2) Put seed wheat to be treated on clean, hard barn floor, or 
in wagon box, or on canvas. The floor, wagon box, or canvas 
should be cleaned with a strong formalin solution, or with boiling 
water. Spread grain out a few inches deep. 
(3) Sprinkle solution over grain with ordinary garden sprink¬ 
ling can. Use about i gallon of solution to each bushel of grain. 
(4) Shovel grain over and over. One person can handle the 
sprinkler while another thoroughly mixes the grain. 
(5) Shovel treated grain into a pile and cover with canvas or 
gunny sacking that has previously been dipped in formalin solu¬ 
tion or boiled in water. Leave covered for 2 or 3 hours. 
(6) Spread grain out not more than 2 inches deep and allow 
to dry. 
(7) Treated grain, if not planted directlv, should be kept in 
smut-free sacks or bins. Disinfect sacks or bins with strong for¬ 
malin solution or boiling water. Drills may be disinfected by 
washing out with strong formalin solution. 
Loose Smut. —The entire head of wheat is affected and turned 
into a powdery mass. It is earlier than bunt, and the smut-masses 
break open immediately after the head appears. At harvest time 
only bare stalks of diseased heads remain. The smut-mass has no 
odor. Smut-balls are not form.ed. Sometimes only a part of the 
grain-head is affected: in such cases it is always the lower part. In¬ 
fection of sound seed always takes place before harvest time. vSeed 
