GARDEN PESTS IN NEW ZEALAND 



Leaves and bark are infested., and a narrow twig may be partly 

 encircled by the margins of the scale. The adult female (Fig. 6f) is 

 oval and dome-shaped, some individuals measuring one-sixth of an inch 

 in length; the surface is smooth, except toward the margins, parallel to 

 which are some wrinkles. The general colour is dark brown, but just 

 prior to egg-laying there are numerous transverse and longitudinal 

 markings of a lighter colour over the surface, The. winter is passed in 

 the egg stage or as partly-grown young. 



Another, but larger, species, closely resembling the preceding, and 

 found 011 grape-vines, wistaria, eleagnus, etc., is Eulecanium berberidis. 

 It is reddish-brown in colour, and measures up to one-third of an inch 

 in length. 



GOLDEN OAK SCALE (Asterolecanium variolosum). This insect is 

 very common upon English oak trees in parts of New Zealand. In many 

 cases so badly are the trees infested, that they become sickly in appear- 

 ance, and at times the greater part, or even the whole, of the tree is killed 

 through the agency of the pest. 



The individual scale (Fig 7, 1) is more or less circular, and about 

 one-sixteenth of an inch in diameter; it is of a greenish-yellow colour, 

 with a narrow paler circumference, though some, with the exception of 

 the rim, are partly or wholly brownish. Each scale forms and lies in a 

 depression of the bark. The insect is viviparous. A minute parasite, 

 Hub role pis dalmanni (note the exit holes made by the parasite during 

 emergence from some of the scales shown in the photograph) has recently 

 been established as a means of control and is proving effective. 



CAMELLIA SCALE (Pulvin&ria camelicola). This European scale 

 sometimes heavily infests camellias and euonymus in New Zealand, but 

 is not a very serious pest, though more so in glass-houses than out of 

 doors. After the female has produced her eggs, she drops off the plant, 

 so that, though the latter shows evidence of injury, there may be no sign 

 of the insect. 



The adult female is oval and about one-third of an inch at its 

 longest length ; in shape it resembles a rather flattened turtle scale, hut 

 when laying eggs the body shrivels and numerous transverse wrinkles 

 develop, although the margins of the scale remain smooth. There is at 

 least one generation each year, and in warmer parts probably a second, 

 which may reach maturity before winter or not till the following spring. 

 The eggs are laid in an elongate, white, cottony sac secreted at one end 

 of the female ; this sac is sometimes as much as four to five times the 

 length of the insect. The eggs continue to hatch over a period of from 

 four to six weeks, and the larvae rapidly spread; the latter settle along 

 the leaf mid-rib, margin, or lower surface. 



APPLE MUSSEL SCALE ( Lepidosaphes ulmi). - - The apple mussel 

 scale is now established throughout the temperate regions of the world. 

 It is commonly met with on apple, but has a long list of host plants, 

 among which are pear, hawthorn, willow, poplar, -gooseberry, and currant. 



The insect (Fig. 7, Xos. 2 and 6) forms incrustations on bark 

 and fruit, and is commonly met with at the stalk end of the apple; the 

 individual scale is chocolate-brown in colour, is shaped like the shell of 

 the salt water mussel hence the name "mussel scale" and when full 

 grown measures one-eighth of an inch long. 



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