260 Agricultural Experiment Station, Ithaca, N. Y. 



Insects Friends and Enemies. 



The insects most eoinmonly found on chrysanthemums are here- 

 named and some descriptions of them and their work, with instruc- 

 tions for the eradication of detrimental kinds, are given to enable 

 the inexperienced to deal with all according to their deserts. 



A7its. — The little brown ants so common in greenhouses and on 

 plants grown therein are not injurious. Occasionally they appear 

 in such large numbers that their presence is objectionable ; but it 

 should be remembered that they are great scavengers, and while 

 working little or no injury to the plants, they clear them of a lot of 

 objectionable matter in the form of dead and dying insects. Their 

 presence should therefore be tolerated. 



Black Aphis.— Entomologists are undecided about the speciiic 

 position of the much dreaded black aj^his of the chrysanthemum, 

 although it is apparently one of the commonest of the plant lice of 

 greenhouses. It multiplies with amazing rapidity, and is found on 

 the young shoots and leaves of many cultivated plants, being very 

 partial to chrysanthemums, deforming the foliage and destroying 

 its vitality. It is easily held in check by the frequent application 

 of pyrethrum powder, or b}^ fumigation with tobacco. 



Caterpillars, — The green caterpillars which abound on chrysan- 

 mums indoors and out, all through the growing season, are very de- 

 structive. They live upon the fleshy portion of the leaves, leaving 

 only the thin epidennal covering of the upper surface, and occasion- 

 ally devouring the leaves bodily. Sometimes they also attack the 

 soft young shoots, treating them in similar fashion. They are easily 

 traced by their work and their blackish excrement, and they should 

 be at once picked oif and destroyed. Usually they are found on the 

 under side of the leaves. 



Chrysopa, — We have a friend in the larvse of the lace wing fly, 

 of the group of insects known to entomologists under the name of 

 Chrysopa, which is an insatiable enemy of aphids and kindred pests. 

 This larva is of greyish color, and nearly an inch in length. It 

 kills and devours the minor insects in large numbers, and in this 

 respect is certainly one of the best helpers of plant growers. The 

 perfect insect is extremely pretty, having beautiful green lace-like, 

 wings and golden eyes. 



Green Fly. — Perhaps the most familiar of all greenhouse insects 

 is the aphis commonly known as the green fly. The young and 

 tender branches of soft-wooded plants are its favorite abode, and 



