IisTSECTs AND Insecticides 
37 
Fig. 30. —The Cottony Maple Scale. Mature females on maple twigs. Larvae of one 
of the lady-bird beetles, Hyperaspis signata Oliv. on leaf at the left. These lady-bird beetles 
feed on scale insects. Natural size. (After O. E. Essig, “Injurious and Beneficial Insects 
of Calif.” Calif. State Com. of Hort.) 
Remedies .—Kerosene emulsion (lo), 15% kerosene, used during 
the dormant season, will be found fairly effective. 
Tobacco extract (19) or kerosene emulsion (10), that is 7% 
kerosene, will destroy the young insects, but it is difficult to strike all 
of them on the under side of the leaves. If a strong current of water 
can be used, many of the young insects can be washed to the ground 
where they will perish. 
Elm Scale .—The young lice hatch in June or early July and feed 
UDon the leaves until fall, when they return to the bark, insert their 
beaks and hibernate during winter. In the spring the eggs are de¬ 
posited under the body and a partial iscale formed over the females. 
The presence of the insects is best indicated by the partial scale which 
consists of a white, waxy ring secreted about the insect. Infests elms 
only. See Fig. 31. 
Remedies .—In Nevada where this has been quite a serious pest, 
best results have been obtained by using soluble oils (12), i part to 15 
parts water, during the dormant season. For summer treatment use 
kerosene emulsion (10) or tobacco (19), as recommended for the maple 
scale. 
Oyster-Shell Scale .—In some sections of the State this scale is 
quite bad on the ash and lilac. For description and remedies, see under 
Apple and Pear, Bark and Wood. 
