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plication of manure from a farm where it has already gained a foot hold 1 
When it once gets into the soil will it persist as milk-weed, quack-grass, 
and Canada thistle do ? ” 
The answer to the first question depends upon when and where the 
germinating spore enters the wheat plant. It has been pretty well set¬ 
tled that the plant is infected at the time of germination, and the germ 
tube enters near where the plantlet is attached to the grain. The prac¬ 
tical application of this fact is that grains covered with soil can only 
receive infection from spores that were sown with the seed or already 
existed in the soil, but that smut will not spread during the growing 
season from field to field or from plant to plant. 
The answer to the second question is a logical sequence of the pre¬ 
ceding. If a crop has any portion smutted it is more than probable 
that the spores of smut will get in contact with the sound wheat ker¬ 
nels. One crushed kernel thoroughly distributed through a bin of seed 
wheat may result in many dollars’ loss when the crop is harvested. 
Other sources of contamination are also given, viz : The thrasher hav¬ 
ing previously been used for smutted wheat; being stored in a bin or 
passed through a fanning-mill or seeder not properly cleansed after be¬ 
ing used for smutted wheat ; by using sacks that have not been disin¬ 
fected. 
The third question is answered in the affirmative. It has been shown 
that corn smut can pass through animals and retain its germinating 
power, and the same is likely true of wheat smut. 
Spores retain their power of germination when dry for two or three 
or even more years, but in the field we may safely assume that two 
years will eliminate every trace of it. 
Natural checks to its increase are ably discussed; they are, mainly, 
probability that the spores may not be near enough to the germ end of 
the kernel, insufficient moisture, and resistant varieties. 
The nature of the injury is of a more comprehensive nature than is 
generally supposed. A definite percentage of the crop is actually lost. 
An extra amount of cleaning and screening is required for what is good. 
The wheat is unfit for seed until disinfected. The smut gives the flour 
a dark color and disagreeable smell. The straw and screenings are lia¬ 
ble to spread the disease when converted into manure. 
Under the heading “ remedies and precautions” the author says that 
the prevention of smut costs not a fraction of the trouble or expense 
that is necessary in removing the Colorado beetle from potato-vines. 
The method of disinfection preferred is a soaking of the seed in a solu¬ 
tion of blue vitriol, and several methods for doing it are given in full. 
The methods of prevention are very emphatically summed up as fol¬ 
lows: “Clean seed upon a clean field will result in a*clean crop.” 
Very little space is given to the black smut; its general appearance, 
habits, and botanical characters are described. The same method of 
treatment as that described for stinking smut is recommended for this 
