GARDEN PESTS IN NEW ZEALAND 



by making holes about four inches deep with a stick in the soil near to 

 the infested plants and pouring in a little carbon bisulphide ; the holes 

 should be closed immediately. To protect strawberry beds, if they are 

 not too extensive, the most satisfactory method is to cover the plants 

 with scrim, stretched on frames, at dusk during November and early 

 December, when the beetles are flying; this will prevent the insects from 

 infesting the ground with their eggs. The use of sulphur smudges, 

 already referred to, is of great importance in this respect. 



SnrruREAXi'AX GRASS CATERPILLARS. These caterpillars are the 

 larvA? of native moths (Fig. 12, fl) belonging to the genus Porina,, and 

 when they become epidemic they cause much more extensive damage to 

 pasture and lawns than do the grass grubs. When full grown, the 

 greyish-black caterpillars (Fig. 12, f2) reach a length of about three 

 inches; they are soft-bodied and rather flaccid, and live in underground 

 burrows of varying depth. After dark, these caterpillars come to the 

 surface and devour the grass, eating it close to the ground, much soil 

 being swallowed by the larvae during the feeding. This soil is evacuated, 

 and resembles earthworm castings, but is mixed with silk spun by the 

 caterpillars; the emergence holes of the caterpillars, about the diameter 

 of a lead pencil, are conspicuous on the surface denuded of its covering 

 of grass. Pupation takes place underground, and when the moths 

 emerge the pupae first move to and project beyond the sin face of the 

 ground; these pupae are large and easily recognised by the wing-cases, 

 which are very short compared with the length of the body. The 

 moths are on the wing during spring and summer, the rest of the year 

 being spent in the larval stage. The moths are night-flyers, and are 

 amongst the largest species in New Zealand, their wings having an 

 expanse of frorn one to over two inches; they are heavy-bodied insects, 

 and vary considerably in colour. One of the commonest species is 

 brownish-yellow, or sometimes a smoky-grey, with a white streak bordered 

 with black on the fore wings; the hind wings may be pinkish. 



The most satisfactory method of controlling the insect is to 'roll 

 infested lawns after dark, in order to crush the caterpillars whilst feed- 

 ing on the surface. Flooding an infested lawn with water will bring 

 most of the caterpillars to the surface, when they can be collected and 

 destroyed. Spraying, grass in spring and early summer with arsenate 

 of lead will tend to poison the immature caterpillars. There are at 

 least three species of insect parasites that attack these larva?, and there 

 is also a fungus which invades and destroys the whole body, taking the 

 shape of the insect; such fungus-infested caterpillars are commonly 

 called "vegetable caterpillars." 



WIRKWORMS. The roots of garden plants and germinating seeds 

 are often damaged by hard, wiry beetle grubs, reddish-brown or whitish 

 in colour, called "wire worms," so named from their resemblance to short 

 pieces of wire; they have three pairs of legs behind the head and a 

 sucker-like appendage on the last body-segment (Fig. 12, g2). These 

 grubs transform 'to narrow-bodied, brownish or blackish beetles, known 

 afritfelic'k-beetlestt ^Fig. 12, gl) from their habit, when overturned, of 

 righting themselves by a springing action, during which a distinct and 

 sharp clicking sou.nd- is made; ihe spring apparatus Consists of a spine, 

 the tip of which fits into a notch; on tjie under side of the thorax. 



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