GARDEN PESTS IN NEW ZEALAND 



Practically nothing is known as yet in regard to the biology of the 

 New Zealand click-beetles. They are extremely difficult to control, and 

 the larval stage covers a period of two or more years. 



NARCISSUS FLIES. There are two species of narcissus flies the 

 larger (Merodon equestrix) and the smaller (Eumerus strigatus) both 

 occur in New Zealand. The larvae of these flies attack bulbs of various 

 kinds, the hosts of the larger fly being narcissus, hyacinth, tulip, 

 amaryllis, habranthus, vallota, galtonia, scylla, and leucojum ; and of 

 the smaller fly, narcissus, hyacinth, onion and shallot. These flies are 

 two-winged insects, the hind wings being wanting as such, arid belong 

 to a group called the syrphid, or hover flies. 



The larger narcissus fly (Fig. 12, hi) resembles somewhat a 

 liumble-bee (which, however, has four wings) ; its stout and very hairy- 

 body measures about half an inch long. There is considerable variation 

 in colour, though black or brown predominates, with greyish or yellowish 

 hairs, and bands of the same colour; the bands, however, are absent in 

 some individuals. 



During spring the insects fly about in the sun, and lay their eggs 

 at the leaf bases of the host plants, or on the exposed neck of bulbs, or 

 in the soil close by. The larvae, which are legless, yellowish grubs, enter 

 the bulb, and may completely destroy it. Infested bulbs may be 

 detected by an unnatural softness near the neck when pressed between 

 the fingers. 



The smaller narcissus fly (Fig. 12, h2) is about half the length of 

 the larger, of a shiny black colour, with metallic reflections, and is not 

 clothed with hair. The eggs are laid in the ground, or at times upon 

 the plant itself. Several larvae of this fly may be found in the one 

 bulb; the larvae resemble those of the larger fly, but are smaller, and 

 have three small processes at the end of the body. The smaller narcissus 

 fly usually attacks the bulbs already damaged by some other agent, 

 though' it lias been known to infect sound bulbs. 



Control of both these flies depends upon the destruction of infested 

 bulbs. Recent researches have shown that the flies themselves can be 

 poisoned in large numbers by a spray made of 4oz. of sodium arsenate, 

 lib. of crude glycerine, 21b. of white sugar, and four gallons of water; 

 this spray is applied during bright and warm weather. 



SPRINGTAILS. These are very minute, soft-bodied insects, which 

 are very active, and have a habit of springing with the agility of fleas. 

 There are several species, but two are of interest to the horticulturist. 



One of these (Fig. 12, kl) is white in colour, narrow-bodied, and 

 lives underground, especially in damp places, where it damages ger- 

 minating seeds, or the roots of seedlings; even older herbaceous garden 

 plants are attacked. As a control, it is important to drain the soil in 

 damp locations and to dig in calcium cyanide about two weeks before 

 planting or sowing. 



The second species is blackish and more or less spherical (Fig. 

 12, k2) ; at times it does considerable damage in the spring to the seed- 

 leaves of young plants as soon as they appear above ground. Spraying 

 small areas e.g., of cucumbers, turnips, etc. with black-leaf 40 would 

 help to protect the plants; as the eggs are laid in the ground, and as 

 these develop best under moist conditions, thorough cultivation prior 

 to sowing the crop is an important controlling factor. 



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