GARDEN PESTS IX XEW ZEALAND 



Natural enemies in Xew Zealand are two species of hymen opterous 

 parasites, Aplielinus fuscipennis and A. mytilaspidis, the latter^ also 

 attacking the apple mussel scale. Ladybird beetles also feed upon the 

 insect. 



- Control requires close attention, and can be effected by the applica- 

 tion of lime-sulphur in the dormant season, when it is essential to apply 

 a strong wash to kill off as many scales as possible before reproduction 

 commences in the spring. At bud movement further applications are 

 necessary to destroy the young insects. 



A 



BED ORAXGE SCALE (Chrysomphalus nurantii). The red orange 

 scale is distributed throughout the world, and is especially abundant in 

 tropical and sub-tropical regions, the most southern limit being Xew 

 Zealand. As a major pest it is peculiar to citrus, but infests to a minor 

 extent other plants e.g., plum, apple, pear, quince, grape, fig, 

 euonymus and rose. So far it has been found only on citrus in New 

 Zealand, it being well established in the Auckland province, and also in 

 the South Island on Banks Peninsula. It is very often found on 

 imported oranges and lemons. 



This scale is a circular one, with a central pimple-like prominence, 

 as in the case of the San Jose, but is natter, about half as large again, 

 and is of a characteristic reddish colour. The damage done to citrus 

 trees by this insect is of a serious nature, as the entire tree or part of 

 it may be killed in severe infestations. A characteristic feature of this 

 species is that no honey-dew is secreted, and hence there is a total absence 

 of sooty mould on infested trees. 



Like the San Jose scale, the red scale is viviparous, and over- 

 winters as partially mature adults, completing development in early 

 spring, when the young insects make their appearance. An average of 

 about 55 young is produced by each female, and development to maturity 

 takes from two or two and a-half 'months; about one month later young 

 are produced, and their production continues over a period of one or two 

 months; climatic conditions, however, have a direct influence on 

 development. 



An important natural enemy is the steel blue ladybird (Orcus 

 chalybmus) , imported from Australia; but the most efficient control is 

 cyanide fumigation, or spraying with red oil or lime-sulphur. 



THE BLACK SCALE (Chrysomphalus rossi). Foliage of palms, 

 oleander and citrus is often infested by this reddish-black to black 

 circular scale (Fig. 7, 3) ; it is almost flat, with a central whitish spot, 

 and measures up to one-tenth of an inch in diameter ; when many indi- 

 viduals are crowded together, their outline becomes irregular. This 

 species is not especially injurious, though common. 



OLEANDER SCALE (Aspidiotus hederce). This cosmopolitan insect 

 occurs on orchids, oleander, ivy, camellia., palms, citrus, coprosma, and 

 karaka, infesting stems, leaves and fruit. In the case of citrus, this 

 insect delays colouring of the fruit, which becomes blotched with yellow 

 or green. The insect may be so numerous, that it completely covers the 

 whole plant, giving to the latter a white appearance; this is due to the 

 preponderance of white male scales, the female being slightly yellow, 

 with a purplish tint. 



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