INSECT AND OTHER PLANT ENEMIES. 



93 



either side. They feed on all sorts of vegetable 

 crops, and abound everywhere over a large area 

 of the globe. There are two broods — one in 

 April, and the other from July to September 



Fig. 115.— Silver V Moth (Plusia gamma). 

 1. Eggs. 2. Caterpillar. 3. Chrysalis in cocoon. 4. Moth. 



inclusive. The silken cocoons are hung up to 

 the food plants. 



Remedies. — Clean culture, that is, keeping the 

 ground clear of weeds, especially nettles, is of 

 the first importance. The caterpillars being 

 large and conspicuous, a good plan in the case 

 of many vegetable crops would be to tie some 

 broom or birch branches together, making a 

 light switch or besom with which to beat the 

 plants without injuring the leaves, yet sufficient 

 to knock down the caterpillars, so that they 

 may be trodden by one or two boys following 

 the beater. This could be repeated at intervals 

 of a few days, until no more caterpillars are 

 observable. Looking for and collecting the 

 cocoons would save much mischief later on. 

 Young plants of all the Cabbage tribe, as well as 

 Peas, Beans, and Beet, would be encouraged to 

 grow by drenchings of liquid manure, while the 

 wetting of the foliage would destroy many of 

 the caterpillars. This should be done in moist 

 weather, otherwise the ground should be well 

 moistened with clear water previously. 



Slugs and Snails. — There are several very 

 common species of these pests, but none is more 

 widely distributed or more mischievous than 

 the Black Slug (Limax ater), which is deeply 

 wrinkled and furnished with a rough shield 

 carried upon the shoulders when crawling. It 

 is often deep -black, but varies to a chestnut 

 hue. The Milky Slug (L. agrestis) is whitish or 

 ashy-gray, with black horns and a yellow shield. 

 Like the former, this is very common, and 

 though both are most destructive during spring 

 and autumn when moisture is abundant, yet 

 they are to be dreaded all the year round when 

 moist, mild weather favours their activity. 

 Droughty weather and frost in winter constitute 

 the greatest natural checks to their depreda- 



tions. The Garden Snail (Helix hortensis) may 

 readily be recognized by its large convoluted 

 shell of a yellowish hue, more or less marbled, 

 and variegated with dark markings. The occu- 

 pant of the shell comes out when about to travel, 

 and is then seen to be wrinkled and whitish, 

 with a slate-coloured head and back. It is most 

 destructive to plants on and near walls, fences, 

 and palings, where it can find shelter and hid- 

 ing-places. The Garlic Snail is a name given 

 by gardeners to a small, flattened, slaty-blue or 

 gray species which gives most trouble in hot- 

 houses, especially to Orchids. 



Remedies. — Hand-picking is the most effective 

 remedy for slugs and snails of all kinds, not- 

 withstanding the fact of its being a very tedious 

 process. It should be carried on incessantly in 

 spring, when so many tender plants are coming 

 up, or have just been put outside from houses 

 and frames. Naturally the most valuable plants 

 will receive the first and best attention. The 

 early morning and moist evenings are the best 

 times to go collecting slugs. On a large scale, 

 and when time is valuable, dustings of wood- 

 ashes and charcoal-dust will save many plants. 

 In certain cases, such as in plantations of the 

 Brassica tribe, a good sprinkling of salt over the 

 ground when the slugs are out, during moist 

 evenings or mornings, is a good remedy. Equally 

 efficient is strong lime-water spread over the 

 ground with a coarse-rosed watering-pot; this 

 causes the slugs to cast their slimy coating, so 

 that many will crawl away and recover. To 

 prevent this, the remedy should be repeated the 

 same or the following day, before they have time 

 to repair the previous injury, and they will 

 certainly be destroyed. Avoid wetting the 

 plants with strong solutions as much as possible. 

 Traps of Cabbage and Lettuce leaves, as well 

 as pieces of board loosely laid on the soil, will 

 enable the cultivator to secure large numbers 

 of the pest in the vicinity of valuable plants. 

 Kings of wood-ashes, coal, and charcoal dust, as 

 well as coal-ashes, put round valuable plants, will 

 save them in most cases unless there are slugs 

 already inside the ring. The song -thrush or 

 mavis and blackbird destroy large numbers of 

 slugs and snails, and should be encouraged in 

 and about the garden. "When plants in borders 

 are being devoured, apparently without the 

 agency of slugs, search under the leaves of ivy 

 and other climbers upon walls, wooden fences, 

 and under projecting ledges of wood or stone, 

 where snails will in all probability be found 

 hiding during the day, for they feed mostly at 

 night. The Garlic Snail may be trapped with 



