“SUMMER SPORES” OF THE FUNGUS 
These strings or “horns” of conidia are extruded from the pustules of the fruiting fungus on 
all the cankered limbs. At first the conidia are bright yellow or greenish yellow, but they 
gradually turn darker with age. These conidia are by no means always present, however, 
and in some cascs, as in young nursery stock, it is exceedingly difficult for anyone except 
an expert to detect the presence of the fungus. (Figure 6.) 
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