376 THE COMPLETE GARDEN 



Winter-killing: 



The death of plants in winter due generally to sudden changes of tem- 

 perature or to the ground becoming frozen too deeply. 



Yellows: 



A diseased leaf condition due to the breaking down or oxidizing of the 

 plant leaf tissue caused by a ferment. 



Zone (Planting) 



An area characterized by a planting season of similar duration and 

 dates for beginning and ending. 



