Insects and Preventives 



panding flower buds. It feeds upon the plant, by piercing the tissue and suck- 

 ing the contents of the cells. Its presence may be discovered by the twisted 

 and curled condition of the young growths, and also by the marring of the 

 petals as the flower is opened. Sometimes thrips injures the buds so seri- 

 ously that the petals are glued together, and the blooms fail to open. 



The thrips seems to have become more prevalent each year during the 

 past five seasons, and in some places has increased to such an extent as to 

 almost destroy crops of carnations at certain periods. Its increase in the 

 Eastern States has been such, that in certain localities it is impossible to 

 grow marketable carnation flowers in the open ground. It can, however, be 

 kept under control in the greenhouses, the principal remedy being heavy 

 fumigation with tobacco stems. Some growers have recommended fumi- 

 gating with red pepper, but so far as I have experimented with this substance 

 it does not seem to be very efficient. Repeated, heavy fumigations with 

 tobacco stems will keep the thrips in check to some extent, but owing to the 

 fact that this pest is generally concealed in the enfolded bud, it is impossible 

 to reach all of the insects by one fumigation, or even by several ; therefore, 

 it is much more difficult to eradicate than red spider. 



A patented compound, manufactured in England and sold under the 

 name of "X L All," has been successfully used in destroying thrips, and has 

 proved more efficient than the ordinary fumigation with tobacco. It is, 

 however, very expensive at the present time ; in fact, so costly as to be 

 beyond the reach of the ordinary carnation grower. It is furnished in small 

 cakes, each cake being sufficient for one thousand cubic feet of space. It is 

 used by vaporizing the cakes, either by means of a special lamp made for the 

 purpose, or upon an ordinary tin pan placed over an alcohol lamp. This 

 vaporizing is done just at night, and the houses closed and locked for the 

 night. In order to get the best results with the employment of this com- 

 pound, it is necessary to use it several times consecutively ; that is, vaporizing 

 the house upon one night and following with another vaporization, either the 

 succeeding night or the second night after. If this be repeated once in two 

 weeks, the thrips will be held in check, and the damage therefrom much re- 

 duced. 



Cut Worms 



Ordinary black or variegated cut worms occasionally injure young car- 

 nation plants in the field, cutting off the foliage or gnawing out the terminal 

 shoot immejdiately after the plants are set out. The injury done by cut 

 worms to young plants is, however, of comparatively little moment. These do 



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