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dust-like spores, and if it is afterwards used to thresh a crop in 
which no smut is present, the kernels may become contaminated. 
In this way the smut appears the next season on a farm where it 
has been previously absent. Clean seed may also be contaminated 
Fic. 2. Loose smut of wheat. At the left is a normal head, the head 
Beattie it showing a few normal spikelets at the tip. 
by being placed in sacks which have contained smutted wheat. In 
the same way a contaminated drill may be a source of smut when 
clean seed is used. These spores, sown with the seed, germinate 
