DISEASES AND INSECTS. 91 



INSECTS. 



The insects destructive to Orchids are the wood-louse, 

 the cockroach, the red spider, the white and brown scale, 

 thrips, green fly, small ants, slugs, snails, and mealy-bug. 



The wood-louse is found in every part of the Orchid 

 house. It attacks every part of the plant, but chiefly 

 feeds on the tender spongioles of the roots, the young 

 shoots, and the flower buds. 



Even plants in baskets are not safe from their attacks, 

 for they will run along the rafters and drop upon the 

 plants. They hide under the pots or in the drainage. 



The common way to destroy them is to cut potatoes in 

 halves, scoop them out, and lay them along the tables of 

 the house. The insects will take refuge in these, and 

 great numbers may thus be destroyed. 



If, however, this means becomes insufficient on account 

 of numbers, they may be destroyed by hot water. To do 

 this allow all the plants to remain unwatered about thirty- 

 six hours, that the soil may become dry. Have a pan of 

 water heated to about 70 Fah. and into this plunge the 

 pots about to the middle. All insects which have taken 

 refuge in the drainage will seek to escape at the top and 

 are easily destroyed as they fall into the water and per- 

 ish. This operation should be performed upon all the 

 plants in the house the same day. The hot water will 

 not hurt the roots of the plants, but the pots should only 

 remain plunged a few moments and the operation should 

 not be often repeated. 



Cockroaches are most destructive in an Orchid house, 

 and in a few nights they may do a great deal of mischief. 

 They feed upon the tender roots and flower stems. The 



