186 



PESTS OF GARDEN AND FIELD CROPS 



The Celery Leaf-tier, or Greenhouse Leaf-tier (Phhjctcenia ferrugalis 



Hbn.) 



A variet}' of garden and field crops including celery, beets, tobacco, 

 and others are damaged by this insect. In addition it is injurious on 

 plants grown under glass, especially roses, carnations, and chrysanthe- 

 mums. 



The larvae usually bend a part of a leaf over on the rest, or fasten two 

 leaves together with silk, feeding within. They are whitish caterpillars, 

 with a green stripe down the middle of the back. The head is light 

 brownish, and is marked with dark dots. When mature, the caterpillar is 



Fig. 228. — The Celery Leaf - 

 tier. Larvae. Original. 



Fig. 229. 



—Adult of the Celery Leaf- 

 tier. Original. 



three fourths of an inch long. There are two or three generations out- 

 doors, and an indefinite number in greenhouses. 



Since the caterpillars feed for the most part concealed, poisons must 

 be applied early in order to be at all effective. Paris green or arsenate 

 of lead may be used. Hand picking is advisable wherever it can 

 be practiced economically. 



The Clover-hay Worm {Hypsopygia costalis Fab.) 



Late in winter the lower layers of clover hay in stack or mow often are 

 found matted together with silk. When the hay is turned over, active 

 wriggling worms are dislodged. In spring the silk cocoons of the pupae 

 will be observed, here and there in the mass. 



The adult, a small moth expanding less than an inch, emerges in 



