BORERS. 



BORERS. 



branch. The history of this insect was first 

 made public by Professor Peck, who called it 

 the oak-pruner, or Stenocorus (Elaphidion} 

 pututor. In its adult state it is a slender long- 

 horned beetle, of a dull brown colour, sprinkled 

 with gray spots, composed of very short close 

 hairs ; the antenna? are longer than the body, 

 in the males, and equal to it in length in the 

 other sex, and the third and fourth joints are 

 tipped with a small spine or thorn ; the thorax 

 is barrel-shaped, and not spined at the sides ; 

 and the scutel is yellowish white. It varies in 

 length from four and a half to six-tenths of an 

 inch. It lays its eggs in July. Each egg is 

 placed close to the axilla or joint of a leaf- 

 stalk or of a small twig, near the extremity of 

 a branch. The grub hatched from it penetrates 

 at that spot to the pith, and then continues its 

 course towards the body of the tree, devouring 

 the pith, and thereby forming a cylindrical 

 burn>\v, several inches in length, in the centre 

 of the branch. Having reached its full size, 

 which it does towards the end of the summer, 

 it divides the branch at the lower end of its 

 burrow, by gnawing away the wood trans- 

 versely from within, leaving only the ring of 

 bark untouched. It then retires backwards, 

 stops up the end of its hole, near the trans- 

 verse section, with fibres of the wood, and 

 awaits the fall of the branch, which is usually 

 broken off and precipitated to the ground by 

 the autumnal winds. The leaves of the oak 

 are rarely shed before the branch falls, and 

 thus serve to break the shock. Branches of 

 five or six feet in length and an inch in diame- 

 ter are thus severed by these insects, a kind 

 of pruning that must be injurious to the trees, 

 and should be guarded against if possible. By 

 collecting the fallen branches in the autumn, 

 and burning them before the spring, we pre- 

 vent the developement of the beetles, while we 

 derive some benefit from the branches as fuel. 

 " It is somewhat remarkable that, while the 

 pine and fir tribes rarely suffer to any extent 

 from the depredations of caterpillars and other 

 leaf-eating insects, the resinous odour of these 

 trees, offensive as it is to such insects, does 

 not prevent many kinds of borers from bur- 

 rowing into and destroying their trunks. Se- 

 veral of the Capricorn-beetles, while in the 

 grub btate, live only in pine and fir trees, or in 

 timber of these kinds of wood. They belong 

 chiefly to the genus Callidium, a name of un- 

 known or obscure origin. The larvce are of 

 moderate length, more flattened than the grubs 

 of the other Capricorn-beetles, have a very 

 broad and horny head, small but powerful 

 jaws, and are provided with six extremely 

 small legs. They undermine the bark, and 

 perforate the wood in various directions, often 

 doing immense injury to the trees, and to new 

 buildings, in the lumber composing which 

 diey may happen to be concealed. Their bur- 

 rows are wide and not cylindrical, are very 

 winding, and are filled up with a kind of 

 compact sawdust as fast as the insects ad- 

 vance. The larva state is said to continue 

 two years, during which period the insects 

 cast their skins several times. The sides of 

 the body in the pupa are thin-edged, and finely 

 notched, and the tail is forked. 



" One of the most common k <nds of CaUi- 

 dium found here is a flattish, rusty black 

 beetle, with some downy whitish spots across 

 the middle of the wing-covers ; the thorax is 

 nearly circular, is covered with fine whitish 

 down, and has two elevated polished black 

 points upon it; and the wing-covers are very 

 coarsely punctured. It measures from four- 

 tenths to three-quarters of an inch in length. 

 This insect is the Callidium bajulus ,- the 

 second name, meaning a porter, was given to 

 it by Linnaeus on account of the whitish patch 

 which it bears on its back. It inhabits fir, 

 spruce, and hemlock wood and lumber, and 

 may often be seen on wooden buildings and 

 fences in July and August. We are informed 

 by Kirby and Spence that the grubs sometimes 

 greatly injure the wood-work of houses in 

 London, piercing the rafters of the roofs in 

 every direction, and, when arrived at maturity, 

 even penetrating through sheets of lead which 

 covered the place of their exit. One piece of 

 lead, only eight inches long and four broad, 

 contained twelve oval holes made by these in- 

 sects, and fragments of the lead were found in 

 their stomachs. As this insect is now com- 

 mon in the maritime parts of the United States, 

 it was probably first brought to this country by 

 vessels from Europe." (Harris.} 



The violet Callidium, is of a Prussian blue 

 or violet colour, its length varying from four 

 to six-tenths of an inch. It is found in great 

 numbers on piles of pine wood, from the 

 middle of May to the first of June, and the 

 maggots and pupa? are often met with in 

 splitting the wood. They live mostly just 

 under the bark, where their broad and winding 

 tracks may be traced by the hardened saw- 

 dust with which they are crammed. Just 

 before they are about to be transformed, the 

 larva or worms bore into the solid wood to the 

 depth of several inches. In Maine and other 

 places they are said to be very injurious to the 

 sapling pines. Professor Peck supposed this 

 species of borer to have been introduced into 

 Europe in timber sent from this country, as 

 it is found in most parts of that continent 

 that have been much connected with North 

 America by navigation. It is somewhat sin- 

 gular that Europe and America should have 

 thus interchanged the porter and violet Cal- 

 lidium, which, by means of shipping, have 

 now become common to the two continents. 

 (Harris.} 



Sucrar Maple Borer. -The sugar-maple, tne 

 of the most beautiful and noble trees of the 

 American forest, suffers much from the attacks 

 of a borer, the largest known species of Clytus, 

 by which it is sometimes entirely destroyed. 

 In order to check the devastations of tl 

 borers thev should be sought for in the spring, 

 when they may be readily detected by the saw- 

 dust thrown out of their burrows ; and, by a 

 judicious use of a knife and stiff wire tht 

 may be cut out or destroyed before they hav. 

 gone deeply into the wood. (Hams.} 

 Locust-tree Borer.-The locust tree or acac a 

 is also preyed upon by a borer of the C 

 family, the larva of a painted beetle often seen 

 in abundance feeding by day upon the bio, 

 soms of the golden rod (StKdago), in fee m 

 S 



205 



