Bark Beetles

Overview

Bark beetles are the small borers that live between the bark and the wood of a living tree, and in numbers kill it. In the Elderweald they are the slowest of the forest's dangers and the hardest to answer, because the Wood Elves will not fell a living tree to stop them.

Appearance

A bark beetle is no bigger than a grain of rice: a hard, cylindrical body, dark brown to black, blunt at both ends, with a rough, pitted back that ends in a short slope ringed with tiny teeth. Few people ever see one. What they see is the sign: a scatter of round holes like shot in the bark, little heaps of red-brown dust in the crevices and at the foot of the trunk, and beads of sap that weep from the holes and harden pale. Peel a strip of dead bark and the wood beneath is carved into galleries, a straight channel with fine side-channels running out from it like the veins of a leaf, or like writing. A tree under heavy attack smells sour and resinous, and on a still summer evening its trunk ticks faintly.

Habitat and Range

They live in old timber wherever it stands: the never-cut stands of the deep weald, its lighter margins, and the foothill pine of the Headwater Marches. In an ordinary year they keep to fallen and dying wood. After a drought or a storm, when many trees stand weakened, they rise in numbers and go into the living.

Behaviour and Temperament

A pair bores in through the bark, cuts a mother gallery, and lays eggs along it; the grubs eat outward, each in its own channel, until the bands of living wood under the bark are cut through and the tree can no longer carry its sap. Beetles find a weakened tree by its smell and call others to it, so a single failing tree can become a stand of them in two summers. They take no notice of people.

Life Cycle

Eggs laid in spring become grubs that feed through the summer, rest in small chambers at the ends of their galleries, and emerge as grown beetles to fly to the next tree. A warm year may see two broods. A great tree they have girdled can stand dead for years, its bark sloughing off in plates to show the carved wood underneath.

Uses and Dangers

They give nothing but deadwood. Their cost is the trees: a stand of foothill pine lost in two years, a grove's great tree dying from the crown down. Headwater woodcutters fell and burn an infested tree before the beetles fly, and fell its neighbours with it. In the Elderweald that answer is closed. A grove must decide together how far to let a tree die, whether to strip loose bark by hand, and whether to let the next tree be taken, and the argument can run longer than the beetles do. Wardens of Nature Magic can read where a stand is failing; they cannot make a girdled tree carry sap again.

Lore and Belief

Wood Elves say the galleries are the tree's own last writing, and some groves read them before the tree is let fall. Edge villagers call the beetles the engravers and believe a tree they choose has been wronged by someone, which the Elves do not say aloud but do not deny. Headwater woodcutters hold that a beetle year follows a dry one, which is true.

Where It Appears

• Overview: Animals