386 BOARD OF AGRICULTURE. [Pub. Doc. 



to increase rapidly in numbers unless held in check by some method 

 of treatment. 



When the thrips work on the leaves, small spots where the sucking 

 has taken place soon turn brown, giving the leaf a speckled appearance. 

 On flower buds small pale blotches soon show on the petals, spoiling 

 the blossoms. The cucumber and carnation are perhaps the most 

 usual food plants of this insect in the greenhouse. 



Cutworms. 



Cutworms are the caterpillars of a group of moths known as Noc- 

 tuidce, the caterpillars feeding in a variety of ways, though many — 

 perhaps most of them — attack the stems of succulent plants at or near 

 the surface of the ground, and by feeding at one spot "cut" off the 

 stem at that point. 



Cutworms usually get into the greenhouse by being brought in with 

 the soil, so that if this has been sterilized properly they are not likely 

 to be present, though in some cases it is possible that the moths may 

 enter through open ventilators and lay their eggs, from which the 

 cutworms will hatch. 



The cutworms usually feed at night, burrowing into the ground 

 during the daytime; and the first indication of their presence is the 

 discovery of wilting plants, which examination shows to be due to a 

 more or less complete "cutting" off of the stem. 



Sometimes the easiest way to remove these insects is to dig up the 

 soil around the injured plants and find and destroy the worms while 

 they are quiet in the daytime; sometimes a careful examination in 

 the evening by the light of a lantern will reveal them at work; but 

 when neither of these methods is practicable, for any reason, a poisoned 

 mash may be made use of. To prepare this, take sixty pounds of 

 bran or middlings, molasses enough to sweeten well, one pound of 

 Paris green, and water to make a dough or mash. Mix thoroughly, 

 and place a little beside the stem of each plant late in the afternoon. 

 The cutworms coming up to feed at night will find in this mash some- 

 thing which they prefer to the plants, and will be poisoned by it. 

 Smaller amounts than those given above can easily be prepared, using 

 the different materials in their proper proportions. 



Snails. 

 These pests of course are not insects, but are so often troublesome 

 that they are included here. They are really shells, but forms which 

 appear to have nearly or quite lost their shelly covering. They 

 conceal themselves under boards, pieces of bark or elsewhere during 

 the day, and feed at night. As they move along, large amounts of 

 slime or mucus are poured out to aid them in travelling, and this can 

 be taken advantage of in destroying them. Sometimes it is possible 

 to surround plants attacked by snails with air-slaked lime, which 



