246 Bush-Fruits 



ground will destroy them. Arsenical sprays are effective, but owing 

 to the danger of poisoning the fruit, hellebore, one ounce to a 

 gallon of water, is to be preferred. 

 Reference. 

 Geneva, N. Y., Expt. Sta. Bull. 150. 



THE RED-SPIDER 



Tetranychus bimaculatus, Harvey 



This is a minute mite, about one-fiftieth of an inch long, varying 

 in color from pale greenish-yellow to dark crimson-red, with two 

 dark spots at the side of the body. It is a well-known greenhouse 

 pest and sometimes also attacks plants in the open. It thrives best 

 in a hot, dry atmosphere, hence is most prevalent in times of heat 

 and drought. 



Red-spiderk usually work on the under side of leaves under a 

 delicate silken web. The young mites are lighter in color than the 

 adults and have only six legs instead of eight. They continue to 

 breed while conditions are favorable, then hibernate in the ground 

 or underneath rubbish until spring. 



Remedies. Dusting the under side of the leaves with finely pow- 

 dered sulfur, or spraying with a mixture of it at the rate of one 

 pound to three gallons of water with a little soap added, has been 

 found effective. Sulfur is difficult to keep in suspension. To help 

 in this it is recommended to dissolve a small amount of glue in 

 water to be used in first making a paste of the sulfur. Even then 

 constant stirring will be necessary. 



Plain flour paste has been used in California with good results. 

 Care is taken to make the paste smooth, without lumps, diluting 

 to one gallon of water for each pound of flour. It is then cooked, 

 stirring constantly and adding water to offset evaporation. For use, 

 four gallons of the stock solution are added to fifty gallons of water. 

 This too has a tendency to settle and must be kept well agitated 

 while spraying. 

 References. 



Maine Expt. Sta. Kept., 1892:133. 



Col. Expt. Sta. Bull. 152. 



U. S. Bur. Ent. Circ. 166. 



