— 23 — 
THE PLUM-LEAF NAIL-GALL (Jli,ijtoi)tus sp.j 
The leaves of the American varieties of the plum are 
sometimes injured by the production of a large number of 
slender tubular projections standing out from their upper 
surfaces as shown in the accompanying illustration. Inside 
each gall is a large number of very small spider-like insects 
or mites of the appearance of Fig. jq. 
Figs. 18 and 19. — A, plum leaf showing the galls; B, one of the galls en- 
larged and cut to show the interior. 
Remedies — Probably nothing can be done of much 
value while the leaves are on the trees. P'allen leaves 
should be destroyed as far as possiVjle by fire and the trees 
should be spray(id during the winter or early spring with 
Fig. 20. — One of the mites that j)roduce the nail-gails on plum leaves 
greatly enlarged. 
kerosene emulsion of double strength ( an emulsion in which 
the kerosene is about one-seventh of all), or whale-oil soap 
in the proportion of i pound to 4 gallons of water. 
