20 
Colorado Experiment Station 
color^ and alwa3^s works under a slight web which it spins. The work 
of the two are often confused, but they vary a great deal in their life 
histories. The young red spider winters over under the bark of trees 
and rubbish on the ground. The spiders are best distinguished from 
the brown mites by the fine web they spin over the surface of the 
leaves. The young resemble the adults but are lighter in color. See 
Plate 6. 
Femedies. —The remedies recommended for summer use against 
the brown mite will control the spider also. In cities where a strong 
current of water is available, both the mites and spiders may be con¬ 
trolled b_v frequently washing them from from plants and trees. 
Pear Slug. —See under Cherry. 
Fig. 9.—Pear-tree Slug; a, adult fly; b, larva or slug with slimy covering removed; c, 
same as preceding in natural condition; d, leaves showing slugs and their injuries. 
(Marlatt, Circular 26, Second Series, U. S. Dep. of Agr., Div. Entomology.) 
Pear Leaf-Blister Mite. —This is a ver)^ small mite that lives with¬ 
in the tissue of pear leaves, and in some cases apple leaves, causing 
small reddish or brownish blisters. When numerous these may in¬ 
volve the greater portion of the leaves causing them to fall prematurely. 
The mites pass the winter under the bud scales on the trees. 
Pemedies. —Spray while the trees are dormant, with lime and 
sulphur (16-17) kerosene emulsion (lo), or Soulble Oil (12). 
Vagabond or Pnst-Mite of the Pear. —This mite is quite similar to 
the preceding in size and appearance, but feeds entirely upon the sur¬ 
face of the leaves and tender bark of the new shoots, causing a rusty 
appearance and a dwarfing of the foliage. In severe cases the leaves 
curl and the foliage seems scanty. See Fig. 10. 
Pemedies. —Same as for the preceeding species. 
