INSECT AND OTHER PLANT ENEMIES. 



97 



boards between the lines would catch many of 

 the beetles, which have pronounced habits of 

 leaping when disturbed. Keep down all cruci- 

 ferous weeds which would afford food to the 



Fig. 119.— The Turnip-fly or Beetle (Phyllotreta nemorum). 

 1 and 2. Insect (natural size and magnified). 3. Insect feeding. 4 and 5. 

 Eggs on under side of leaf. 6 and 7. Maggot advancing in growth. 

 8 and 9. Maggot full-grown (natural size and magnified). 10 and 11. 

 Pupa (natural size and magnified). 



enemy, and trench the ground in winter to 

 destroy pupae by burying them. 



Turnip Sawfly (Athalia spinarum). — The 

 perfect fly is bright -orange, and even reddish 

 behind the black head, with four transparent 

 and netted wings. They appear in May or 

 earlier, and the females lay eggs to the number 

 of 200 or 300, in slits made in the edges of the 

 leaves. The caterpillars are hatched out in 

 about five days, and proceed to eat the leaves 

 of Turnips from the edges to the ribs. They are 

 greenish-white at first, but soon become jet- 

 black, and have 6 feet with 14 sucker feet. 

 There are numerous broods in a season. 



Remedies. — The caterpillars cast their skins 

 about once a week, and in order to do so they 

 fix themselves to a leaf with their hindermost 

 pair of sucker feet, and then crawl out of the 



Fig. 120.— Turnip Sawfly (Athalia spinarum). 



1. Insect. 2. Natural size. 3. Eggs. 4. Caterpillar. 5. Cocoon. 6. Pupa 



(magnified). 



old skin. Should they be disturbed in the 

 operation, they are unable to fix themselves 

 again, and die in the old skin. A boy would 

 vol. I. 



soon exterminate the caterpillars by lightly 

 sweeping over the Turnips once or twice a week 

 with a light broom of slender twigs. The insect 

 in all stages likes dry weather and bright sun- 

 shine, but is very torpid on dull or wet days. 

 A good watering from the hose or garden en- 

 gine would probably destroy large numbers of 

 the caterpillars, but benefit the Turnips, as 

 would weak liquid manure. 



Vapourer Moth (Orgyia antiqua). — The 

 male of this moth measures f inch to \\ inch 

 across the expanded wings, Avhich are rich- 

 brown. The fore -wings are shaded with a 

 darker hue, and have a small white spot near 

 the hinder angle. The female has a large, 

 brown body, and only rudimentary wings. The 



Fig. 121.— Vapourer Moth (Orgyia antiqua). 

 1. Male. 2. Female. 3. Caterpillar. 



caterpillar has four brush-like tufts of yellowish 

 hairs on the back, two blackish tufts pointing 

 forwards near the head, and another tuft near 

 the tail pointing backwards. It feeds on Pears, 

 Cherries, Eoses, and other woody subjects during 

 June and the three following months, and the 

 perfect moths appear from July to October. 



Remedies. — The eggs of this species are laid 

 in dense, but neat and regular masses upon a 

 little bundle of gray silk, like a cocoon, and 

 fastened to one or more dead leaves. These 

 may be found in autumn and winter on various 

 plants, but as the female is almost destitute of 

 wings, she must lay her eggs near the spot 

 where she fed in the caterpillar state. The 

 fallen leaves of trees that were infested in 

 autumn or summer should be carefully raked 

 up and burnt, as well as others in the neigh- 

 bourhood. The caterpillars are very conspicuous, 



7 



