200 INSECTS AFFECTING VEGETATION 



small numbers before much harm has been done. Large numbers 

 are sometimes killed at once, so many as to show plainly on the tips 

 of the spears of grass, when one looks along the tips from a level 

 near the ground. The writer has seen the color of a patch of clover 

 and timothy changed from a bright green to a marked greyish tint 

 by the dead bodies of the Iarva3, each on its grass leaf. 



Now this is all very satisfactory thus far. The fungus ordi- 

 narily keeps the beetle in check, and if it stopped at this point all 

 would be well. But unfortunately the dead bodies of the larvae are 

 filled with the substance of the fungus, and this is said to be poison- 

 ous to stock if eaten in sufficient quantity. Mr. G. C. Davis, for- 

 merly of the Michigan station, reports the serious illness of cattle 

 which was clearly due to eating quantities of the dead larvae, al- 

 though no fatalities resulted. We have since that time received ac- 

 counts of similar occurrences. For this reason it will be well to avoid 

 pasturing stock in fields full of the dead larvae until they have had 

 time to shrivel and fall to the ground. 



Clover Mite. The clover mite is not a true insect but a near 

 relative. It is responsible for much of the whitening of the foliage 

 of clover and some other plants. It is a tiny creature with eight 

 legs. The color is dark red. Minute spherical eggs are laid on trees 

 in the fall, where they are often the cause of alarm among fruit 

 growers, who are apt to consider them some form of scale. The main 

 reason for disliking the clover mite, however, is not because of in- 

 jury done to clover, as that is too obscure to be much felt. The tiny 

 mites have a habit of crawling into buildings in the spring and in 

 the autumn, where they get on furniture, books and tables. They 

 are so fragile that it is next to impossible to even brush them off, 

 they crush so easily leaving a red stain. This is especially disagree- 

 able when they crawl into open books or between papers. A closing 

 of the books or a shifting of the papers is sure to result in tiny, red 

 blotches. 



The best way of keeping these mites out of buildings is to spray 

 the outside of the foundation walls with kerosene, or to coat them 

 with a narrow band of some sticky mixture, such as tangle-foot, 

 printer's ink, or something similar. It is probable that the lime and 

 sulphur sprays, in common use at present, will help to destroy the 

 mite by destroying the eggs. 



Destructive Pea-Louse. Pea-growers, especially those raising 

 peas for canneries, sometimes have difficulty with a green plant-louse 

 of small size, which collects in astonishing quantities on the vines. 

 The same creature is to be found living, at almost any time, on clo- 

 ver and crimson-clover. It is impossible to do much in the way of 

 control when the insect is on clover nor is it often necessary. 



Clover-Head Caterpillar. According to Professor Gillette and 

 Professor Osborn, there are three generations each year with some- 

 times a partial fourth generation. The tiny moths lay their eggs 

 in the clover heads and the larvae, usually one to a head, feed on the 

 forming seeds, destroying all or part in each head. The winter is 



