HANDBOOK ON INSECT ENEMIES OF FLOWERS AND SHRUBS 27 



Figure 42. — Full-grown caterpillar of 

 the larger canna leaf roller. About 

 V/% times natural size. 



that they die, becoming brown and 

 ragged. The full-grown caterpillars are 

 about an inch long, rather transparent, 

 and yellow-white, but they have a 

 greenish appearance after feeding on 

 green foliage. The moth is a uniform 

 light brown. In Florida this species 

 overwinters as larvae and as pupae, 

 and the moths appear in February and 

 March. 



Treatment. — Spray or dust with 

 lead arsenate early in the season when 

 the injury is first observed. Later 

 injury may be prevented or forestalled 

 by hand-picking the injured and rolled 

 areas and destroying the culprits con- 

 tained therein as soon as they appear in 

 the spring. Where only a light in- 

 festation exists, squeeze the leaf areas 

 that are rolled, to kill the caterpillars. 



Prevention. — Clean off and burn the 

 dead plants and trash from the beds 

 during the winter to kill any larvae or 

 pupae contained therein. 



Other Pests of Canna 



Page 



Yellow woolly bear 3 



Greenhouse leaf tier 5 



Spotted cucumber beetle 7 



Corn earworm 29 



Asiatic garden beetle 21 



Fuller's rose beetle 44 



Saddleback caterpillar.. 6 



CHRYSANTHEMUM 

 Aphids 



Although several species of aphids 

 attack chrysanthemum, the chrysan- 

 themum aphid (Macrosiphoniella san- 

 borni (Gill.)) is the one most frequently 

 encountered. This species is distin- 

 guished from the others by its chocolate- 

 brown color and by its habit of cluster- 

 ing on the tender terminal shoots (fig. 

 43) and on the under sides of the leaves. 

 As a result of the continuous draining 

 of the plant juices, the tender growth 

 becomes stunted and the leaves curl up, 

 causing serious disfigurement and even- 

 tually the death of the plants. The 

 honeydew excreted by the aphids serves 

 as a medium for the growth of sooty 

 mold, an objectionable black deposit 

 which ruins the beauty of the plant. 

 The sweet honeydew also attracts such 

 insects as ants, flies, and wasps. The 

 chrysanthemum aphid is very prolific 

 and develops rapidly. A single female 

 may give birth to as many as 100 young 

 at the rate of 4 to 9 individuals a day. 



Treatment. — Same treatment as for 

 aphids in general, discussed on page 9. 



Figure 43. — Chrysanthemum stem 

 heavily infested with aphids. About 

 twice natural size. 



