HANDBOOK OX INSECT ENEMIES OF FLOWERS AND SHRUBS 71 



Pine Tip Moths 



The tips of the new shoots, including 

 the buds, may be hollowed out and 

 killed by the small larvae, or caterpillars, 

 of the pine tip moths. Short, dead 

 needles near the apex of the new shoots, 

 with partially developed or hollowed- 

 out buds, are typical of this type of 

 injury. Young trees, less than 20 feet 

 in height, are most seriously affected 

 and may become stunted and bushy 

 from continued heavy infestation. Sev- 

 eral species of tip moths occur in different 

 parts of the country, the Nantucket pine 

 moth {Rhyacionia frustrana (Comst.)) 

 being the common species throughout 

 the East and South, east of the Mis- 

 sissippi River. The larvae are yellow- 

 ish and about half an inch long when 

 full-grown. The species has one gen- 

 eration in the North, two in the Central 

 States, and at least four in the South 

 each season. The insects pass the 

 winter as pupae in the injured tips. 

 In the northern Great Plains States a 

 variety of this moth occurs which passes 

 the winter in cocoons in the litter or 

 soil. Other species found in the South- 

 west and West, usually have one genera- 

 tion late in the spring and pass the 

 remainder of the year in the ground. 



Treatment. — Cutting off and de- 

 stroying the infested tips containing 

 the insects is about the only means of 

 reducing the infestation. In the East 

 and South this can be done during the 

 late fall or winter. In the northern 

 Great Plains States and the West, 

 remove the tips as soon as the dying 

 needles become evident and before the 

 larvae have left them. Where orna- 

 mental pines are adjacent to native pine 

 timber it is difficult to prevent rein- 

 festation. 



Some protection may be had by apply- 

 ing the sprays as suggested for the pine 

 shoot moth, although its effectiveness 

 has not been tested. The first applica- 

 tion should be made in early spring 

 when the new growth starts. Addi- 

 tional applications may be necessary, 

 depending on the locality. 



PITTOSPORUM 

 Cottony-Cushion Scale 



The cottony-cushion scale (Icerya 

 purchasi Mask.) is now rather widely 

 distributed across the entire southern 

 part of the United States. It feeds 

 by sucking the plant juices from the 

 leaves twigs, and stems, and when 

 abundant it weakens or gradually 

 kills the heavily infested plants. This 



scale insect has been found on a wide 

 variety of vines, shrubs, shade trees, 

 and fruit trees, including such orna- 

 mentals as boxwood, croton, ivy, 

 laurel, pittosporum, and rose. The 

 mature female is somewhat oval and 

 convex, about % inch long, and red or 

 yellowish orange. At the time of egg 

 laying a conspicuous, white, cottony 

 cushion, or egg sac, is formed, which 

 elevates the end of the body. This egg 

 sac is ridged or fluted lengthwise (fig. 

 117), is from % to % inch long, and 



Figure 117. — Cottony-cushion scale on 

 rose stem. About twice natural 

 size. 



contains a mass of small reddish eggs, 

 which soon hatch. About three genera- 

 tions of the insect develop each year, 

 but there is an almost continuous 

 hatching of young during the growing 

 season. This particular scale insect is 

 capable of moving about on the plant 

 during most of its life, much in the 

 same manner as mealybugs. 



Treatment. — Spraying with a misci- 

 ble oil or oil emulsion during the 

 dormant season will give good control. 

 For summer spraying, use a white-oil- 

 emulsion spray, or this spray combined 

 with nicotine (p. 101). applied several 

 times 2 or 3 weeks apart to kill the 

 young. The thiocyanate sprays may 

 be used for the same purpose, as sug- 

 gested for the control of mealybugs 

 (p. 31). Where only a few small plants 

 are involved, the insect may be held in 



