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crawling away from the area. But the trenches must be examined every day, and the beetles collected and destroyed.

On freshly-cleared areas and places already infested, bark-traps should be laid to decoy the beetles. Bark-traps, consisting of pieces of fresh Spruce or Pine bark, should be laid down with the soft inner side next the ground, and weighted down with stones, or freshly cut Pine or Spruce poles may be cut into faggots about 3 or 31 feet long, and a strip of bark about 15 to 2 inches broad peeled off lengthways, before they are laid down, with the barked part resting on the ground. The beetles, attracted by the fresh resinous odour, attack the cambial layer of these decoys, and can easily be collected daily. The beetles will also feed on bundles of fresh Pine branches spread over the fall cleared, and can be collected by being shaken out on sheets spread on the ground to receive them as they fall. When collected, the beetles can be destroyed by pouring boiling water over them.

The beetles will also lay their eggs in specially prepared breeding-faggots, made of small Pine or Spruce thinnings cut to about 3 or 3} feet long, and buried near the ground surface, several being set close to each other and the places marked with a peg for easy recognition. After the eggs are laid, the brood is destroyed by peeling the bark from the sticks. This method is often successful during the second year, when neither the hibernated nor the newly-emerged beetle find other sappy breeding-places among the dried-up stumps on the previous year's fall.

Efforts should always be made to destroy the beetles where they emerge, and such operations should be taken in hand before the young plantations are attacked.

2. The small brown or banded Pine-Weevil (Pissodes notatus) is also in Scotland very destructive to Scots Pine (Fig. 153), as well as to Austrian, Corsican, and Weymouth Pines, and occasionally also Spruce and Larch. It attacks both as larva and beetle ; but in the former stage it is very destructive. The larvæ bore in the bark, and between the bark and the sapwood, gnawing away parts of the latter where the bark is thin. The weevil does not gnaw the bark, but pricks with its proboscis through the bark, right into the sapwood near the base of young plantations from 3 to 6 years old, and then sucks the sap. A badly attacked stem looks as if it had been there pricked all over with a needle. From these punctures beads of resin ooze out. often found along with the large brown Pine-weevil.2

1 A monograph on The Genus Pissodes and its Importance in Forestry, by R. S. MacDougall, will be found in Trans. Roy. Scot. Arbor. Socy., vol. xv., part i., 1896, pp. 25-43, and another on The Biology of the Genus Pissodes, in Progs. of Roy. Socy. Edin., vol. xxiii., 1900. See also Board of Agriculture Leaflet No. 138 (Pine. Weevils).

2 Two other species, P. pini and P. piniphilus, also in Scotland attack Pine pole-woods. The Pine-pole Weevil (P. piniphilus) very much resembles P. notatus, but is rather smaller. It is rusty-brown in colour, with a characteristic rusty-yellow patch on each wing.case. It lives in the thin-barked upper parts of Pine pole-woods, but is also found on older stems, where the female deposits her ova singly in holes bored for the purpose. On hatching out the larvæ tunnel sinuous irregular galleries in the cambium, which gradually increase in breadth, and end in small pupal-chambers made in the sapwood. The beetles appear in June, and the generation may either be annual or may extend over two years when the pairing continues after hibernation. P. pini is about g inch long, and of a red-brown to black-brown colour, with sparse yellow scales on both upper and lower surfaces. It is common in central and N. E. Scotland, and usually attacks old stems of Scots and Weymouth Pines. The damage done by P. pini is no doubt often attributed to the large and the small brown Pine-weevils. Badly injured poles and stems sicken and die off ; and if attacks continue the canopy gradually becomes interrupted. The best protective measures consist in felling poles and stems attacked, when resin is seen oozing out of the punctures made for ovideposition. It is not necessary to peel the bark after felling stems, as the larvæ die when the bark dries.

It is very

Appearance.—The beetle is from što of an inch long. It is dark redbrown in colour, and irregularly covered with small scale - like greyish-white hairs. On the thorax there are six to eight plainly marked small white or yellowish dots. The wing-cases have two broad rusty-red transverse bands bearing white and yellow scales, the upper band being interrupted at the junction of the wings. The proboscis is long and thin (see also footnote to p. 90).

Life-history.—The beetle swarms in April and May, and then lays it eggs (often in small clusters) for the most part under the whorls of 3- or 4- to 8-year-old Pines (Scots and others), and also in Pine-cones and in the bark of sickly dominated poles, from April to September. When the yellowish-white brown-headed larvæ hatch out, they tunnel downwards, eating sinuous star-shaped galleries in the cambium, which terminate in a pupal-chamber formed in the sapwood. On enter

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ing this to pass the chrysalid stage, the vacant space is filled up with bore-dust and wood-chips (Fig. 154). Frequently one may find several of the pupæ embedded just below a whorl of branches. The beetle bores a circular hole and emerges in August or later, pairs and reproduces itself, then hibernates in November under moss, or in the bark-fissures of trees, and comes out again and pairs once more in the following April and May. But the generation is usually annual, though there may be three generations in two years,

Prevention and Exterminative Measures.—When young shoots of plants infested by the larvæ droop and look sickly about July, they should be pulled up and burned. This is the only thorough way of exterminating this pest ; and if persevered in for several years in succession, it ends in almost completely annihilating it. Poles attacked should also be felled and barked ; but it is much easier to recognise attacks on young plants than to detect infested poles.

Prof. MacDougall (Trans. Roy. Scot. Arbor. Socy., vol. xv., part iii., 1898, p. 310) makes the following suggestions :

A great means the forester has in proceeding against this pest, once it has got to work, is the preparation of catch-trees or decoy-stems. These will be sickly plants or trees left here and there in nursery or plantation, or plants can be artificially weakened and left standing, or an older tree can be cut down and allowed to lie as a breedingplace. In consequence of the long.continued life and egg-laying, such trap-plants must be arranged, and visited and renewed, at intervals throughout the whole year, from March till October inclusive.

These catch-trees or traps must be barked or removed before the enclosed brood has reached maturity, and their contents, in the shape of larvæ or pupæ, destroyed. My experience is that, where ripe larvæ have been exposed to the light and weather by a removal of the bed-coverings, they rarely complete their development, yet it is safer not to give them the opportunity. Where the barked stems are not removed, special care must be taken that beds deep in the wood are not overlooked, but their contents destroyed. (This must specially be attended to in the case of P. pini, whose beds can be found deep in the alburnum.)

As thin twigs may be used for breeding in, these, if not removed and burnt, must be slit up for the destruction of enclosed grubs or pupæ. Their yielding to pressure, here and there, will be a guide to their having been tunnelled.

I am certain, from my experiments, that where notatus is plentiful and in such cases perfectly healthy plants can be attacked and will succumb), collecting the imagos would prove very serviceable. This measure could be certainly adopted in nurseries with good results. The beetles would require careful looking for, however, owing to their protective coloration; but favourite places for them are below the whorls, at the bases of the bifoliar spurs, and lying between the buds. I have pointed out that imagos may be found during many months, and new imago issue also, yet the intervention of winter will give rise to a certain seeming periodicity of imago appearance. Collecting, then, will probably be most successful in the spring-time, when the over-wintered beetles and earliest - issuing renew or proceed to their egg - laying, and also from August onwards, when escape will be at its height.

Where the beetles have not yet got a footing, a timely and vigorous rooting out of all suppressed or sickly Pines will go far to prevent injurious attack.

As guides denoting attack we may mention :

(a) The bead-like drops of resin that issue from the wounded bark.
(6) The drooping of the plants, with a reddening of the needles.
(c) The little proboscis punctures.
(d) In young or smooth-barked parts, on the finger being passed over the bark,

little risings may be felt, or little ridges may be seen. These mark the places
of larval tunnels or pupa beds.

3. The Beech leaf-mining Weevil (Orchestes fagi) is a common insect in Britain. It often swarms in millions in Beech-woods, and has lately been very destructive in defoliating Beech-trees to a considerable extent. Though its attacks are not fatal, yet they interrupt the growth of trees infested by beetles in large numbers, as often happens on seed-bearing standards and trees near the edges of compartments. The damage is confined to the foliage and flower-buds of Beech (among woodland trees), though Cherries and fruit-shrubs in orchards are also attacked, the leaves of old trees being selected for ovideposition in preference to those of young ones.

Appearance.—This small black weevil is only about 1 to do of an inch long, and covered with fine grey hairs; the wing-cases have rows of coarse punctures ; the antennæ and legs are light-brown ; and the rostrum, when not in use, is bent

back under the thorax. The thighs of the hind-legs are thick, and formed for springing.

Life-history.— The female bites small holes on the under surface of very young leaves, and deposits one egg in each hole near the midrib, when the Beech-leaves flush in spring. The larvæ hatch out 2 to 3 weeks later, and mine within the substance of the leaf, forming whitish galleries (which soon oxidise to brown), increasing in breadth as the grub grows in size. The damaged leaves turn brown, as if nipped by late frost. The pupal stage is passed in the leaf. The beetles emerge in June, and feed on the foliage and the nut-cupules till autumn, when they descend and hibernate under dead leaves on the ground.

Prevention is hardly possible in woodlands ; but the attacks are least extensive in mixed woods, where insectivorous birds are always most plentiful. Ornamental trees may be sprayed with arsenic solution formed by stirring { lb. Paris-green paste in 100 gallons water, and adding 1 lb. lime. If this does not prove successful, the infested leaves should be picked in May and burned, while the beetles should be shaken down and killed in June.

4. The Oak leaf-mining Weevil (Orchestes querci) is somewhat similarly destructive to Oak foliage.

Ichneumon-parasites are common in both 0. fagi and 0. querci.

5. The Willow and Alder Weevil (Cryptorhynchus lapathi) often gnaws the bark of young shoots of old Willow-trees, and attacks young Alder-trees; but its larvæ do far more damage by burrowing into the wood and forming galleries from which the bore-dust is cast out at the entrance.

Appearance.—The beetle is broad and strongly built, about 1 of an inch long, and is strongly marked by having its wing-covers dark-brown for the first twothirds of their lengths, and white-scaled for the last third. When not in use, its beak rests in a groove under the thorax.

Life-history. The beetle feeds in May and lays its eggs. The grubs soon hatch out and feed till August, when they pupate.

Some beetles emerge in autumn and hibernate in any convenient hiding-place, but most of them remain inside the shoots (either as pupa or beetles) till the spring.

Prevention and Extermination.—Branches or trees badly infested should be cut and burned in July. Trees attacked should be shaken over sheets in May, and the beetles killed.

6. The Hazel Weevil (Curculio (Strophosomus) coryli).-The larva is chiefly found on Hazel, Oak, Beech, and Birch, but also attacks other broadleaved trees and conifers, and hollows out the buds before gnawing the young shoots. The wingless weevil also sometimes, in spring, feeds on the edges of needles and on the bark of young Pine and Spruce, especially of 2-year-old seedlings. It often occurs in large numbers, when it may do a good deal of damage.

Appearance.—This weevil is ļ to I of an inch long, almost spherical, and brownish-grey, with greyish metallic sheen. The basal junction of the wing-cases is black, without hairs or scales; the antennæ and legs are rusty-red. The rostrum has a fine groove along the middle. It is wingless and cannot fly, but crawls up stems.

Life-history.The weevil pairs and lays its eggs about June.

Prevention and Extermination. In nurseries the beetles may be shaken down into vessels containing a little paraffin, or else shaken down and collected ; but they drop to the ground when even slightly shaken, and crawl quickly away. Greasebanding the stems with patent tar prevents the fallen beetles from reas

ascending

C. Lamellicorn or Platicorn Beetles (Scarabæide).

This family is distinguished by their antennæ always ending in a club composed of several “leaf-like" joints, disposed like the arms of a fan, the leaves of a book, the teeth of a comb, or in a series of funnels placed above and within each other. The males often differ from the females in the larger size of their mandibles and in having horn-like projections on the head and thorax-most notably so in the Stag-beetle (Lucanus cervus) often found in Oak- and Beech-woods, but not doing any appreciable injury.

1. The Cockchafer, May-beetle, or White-grub (Melolontha vulgaris).- As a beetle, this insect chiefly attacks broad-leaved trees, and feeds on the leaves and flowers of Oak chiefly, but also on Beech, Elm, Maple, Sycamore, Lime, Horse-Chestnut, Willows, and Poplars. During bad "chafer-years” it almost defoliates the trees attacked. Among Conifers it mainly eats the soft tufts of Larch-needles and the male flowers of Pine. It is, however, as a grub that this insect is most destructive, when it does great damage to young Conifer seedlings and Oaks, especially in loose, porous, sandy soil. From the second year, as a voracious growing grub, it gnaws the tender roots of all kinds of young plants, and especially of perennial grasses, weeds, and young coniferous seedlings, so that the latter soon die off, while older plants sicken when attacked. In seed-beds, where the porous well-prepared soil attracts the female beetle when laying her eggs, and on extensive falls of Scots Pine on light sandy soil grubs are often exceedingly destructive, so that the cockchafer belongs to the very injurious class of insects (Figs. 155, 156).

Appearance.—The beetle (see Fig. 155) is from 1 to 11 inch long. The thorax is black or reddish brown ; the wing-cases and legs are ruddy-brown, and each of the former has five longitudinal ridges, the four depressions between which are covered with fine hairs. The abdomen is black, with five triangular white spots on each side, and gradually terminating in a broad, elongated, and pointed tail. The antennæ have ten joints, the laminæ being 7-jointed and feathery on the male, but 6-jointed, smaller, and narrower on the female. The male can thus easily be distinguished from the female by its feathery-leaved antennæ. The full-grown larva or grub is 1} to 2 inches long. It is thick, fleshy, and dirty-white, the tailend being swollen and darker in colour, and generally bluish, owing to the excrement showing through. It has a thick, yellow-brown head, strong biting jaws, and six long feet attached to the thorax. The chrysalis is brownish - yellow, with two horny processes on the last abdominal segment.

Life-history.—The beetle flies in May and June. After pairing the female seeks open spaces with bare loose soil, into which she burrows, and lays about 70 eggs in all, in clusters of from 10 to 30 at a depth of 2 to 4, or sometimes as much as 6 or 8, inches below the surface. The eggs are creamy-white, and about the size of hemp-seed. This done, she reascends to the surface and soon dies.

The larvæ or grubs hatch out about 4 weeks later. During the first year they feed on grass-roots and decomposing foliage, &c. In autumn they burrow deeper as a protection against winter cold, but reascend nearer the surface in spring, and then begin to feed on the roots of plants (chiefly Scots Pine, Larch, and Spruce) until autumn, when they again hibernate as grubs. Reascending in the third spring, they once more feed on the roots of seedlings and young plants; and as the grubs are nearly full-grown, it is then that they do most damage. Again (for the third time) they hibernate as grubs after burrowing deep into the soil, and in

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