Apple leaves showing nitre injury. Note the characteristic browning along margins. 
(Original in Colorado Experiment Station Bulletin 155, by Headden.) 
way the accumulated nitrates are dissolved and washed out. Ground 
treated in this way should produce good crops. 
Apple Rot, Blue Mold (Penicillium expansum) — Blue mold is 
a destructive rot of ripe apples occurring most commonly in storage. 
Apples rotting from this cause give off a characteristic foul odor. 
The rotted area is soft and bright brown in color and spreads 
rapidly until the entire fruit is decayed. Under very moist conditions 
bluish tufts of spores are formed over the surface of the diseased 
fruit. 
The decay is caused by a fungus which gains entrance through 
bruises or other mechanical wounds. In controlling the rot it is 
therefore important to prevent the skin of the apple from becoming 
injured in any way. One rotten apple in the barrel furnishes spores 
Goloii.mx) Pl.vn'I' Dise.vses 
