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The Citrus Red Spider 



(Tetranychus mytilaspidis Riley) 



The Six Spotted Red Spider 



(Tetranychus sexmaculatus Riley) 



The Almond or Deciduous Red Spider 



(Bryobia pratensis) 



The Silver Mite 



(Hriophyes oleivorus) 



These little creatures, while not belonging to the insects, but 

 to the spider or mite family, are of great interest to the fruit 

 grower. They are very small and difficult to detect, though the 

 bright red color of some are in strong contrast to the leaves and 

 fruit, and with a pocket or miner's glass, they can be seen quite 

 plainly in all their ugliness, for they are perhaps the most repul- 

 sive looking of all our plant pests. 



The Citrus Red Spider infests citrus trees only, but the Bryobia 

 are very plentiful on some deciduous trees, especially the almond, 

 while the sexmaculatus work great havoc with beans, peas and other 

 similar plants. All are more plentiful in the spring, but some are 

 on the trees and plants the year around. 



They suck out the juices of the leaves, leaving a pale colored 

 spot later turning to an ashy gray or yellowish appearance, ana 

 if the infestation is bad, the leaves soon drop. 



The Citrus Spider or mite is bright red when adult, but paler 

 in color when young, and can be detected on both fruit and leaves. 

 The eggs are deposited singly, mostly along the ribs of the leaves, 

 and ^are globular and bright red in color. From a little mast stick- 

 ing up from the top of the eggs, guy threads run to the leaf sur- 

 face all around, probably to anchor the egg more firmly, but a 

 good glass is required to see these guys. 



The Bryobia on the almond, pear, apple, plum and cherry ha? 

 much the same affect on the tree as the Red Spider on the citrus 

 trees, but it can be detected more easily by its eggs, which, with 

 the remains of hatched eggs,, form patches of various sizes, light 

 gray in color, but with the red egg showing through. They will 

 color the fingers red if rubbed on them and they completely hide 

 the bark on which they form. The patches appear first about the 

 buds, but on the almond especially, will sometimes cover the whole 

 of many of the smaller branches. They thrive best in hot weather. 



On plants infested with the sexmaculatus, the eggs show plainly 



