Hickory bark beetle
The hickory bark beetle, belonging to the genus Scolytus and species Quadrispinosus, is a small insect commonly found on walnut, butternut, and pecan trees, primarily in the eastern United States. This beetle, which measures about 1/5 inches (five millimeters) in length, has a long, rounded chocolate-brown body. The hickory bark beetle navigates the tree bark and feeds on the sap and bark using its strong mandibles. Its life cycle includes mating in the spring, with females laying 20 to 60 eggs in the tree wood, which hatch into pale, worm-like larvae that later pupate beneath the bark.
The name "hickory" is derived from the Indigenous American term "powcohiccora," reflecting the cultural significance of these trees. The hickory bark beetle is equipped with protective elytra, which allow it to fly while safeguarding its delicate wings. Although it faces threats from predators such as birds and wasps, the hickory bark beetle is not considered a threatened species, with a lifespan ranging from one to two years. Understanding the hickory bark beetle's role in its ecosystem can provide insight into the health of walnut trees and their surroundings.
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Hickory bark beetle
The hickory bark beetle is most commonly found living in and along the bark of walnut trees in North America. The name hickory is an American slang term from the Indigenous American word powcohiccora. It is used to describe walnut trees and products made from their bark or nuts.
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Curculionidae
Genus: Scolytus
Species: Quadrispinosus
The hickory bark beetle is typically found on trees in the eastern United States. This beetle bores into the bark of walnut, butternut, and pecan trees. The name hickory is an American word which developed from the Indigenous American word powcohiccora. It was recorded by Captain John Smith when the British came to America. The word hickory is used for the tree, the bark, and the nuts of walnut trees. The hickory bark beetle spends most of its time tunneling beneath the bark of these trees.
Growing to a length of about 1/5 inches (five millimeters), the hickory bark beetle has a long, rounded, chocolate-brown body. Like other insects, the hickory bark beetle is divided into the three main parts of head, thorax, or middle-section, and abdomen, or lower section. The head of the hickory bark beetle is rectangular with a pair of short, bulbed antennae. The thorax of the hickory bark beetle is much larger than the thoraxes of most beetles. It is also rectangular in shape and connects the hickory bark beetle's head with its abdomen.
Over the abdomen of the hickory bark beetle is a pair of elytra. Elytra are hard, protective wing coverings formed by the front wings of the hickory bark beetle. The elytra protect the hickory bark beetle's delicate rear wings from possible damage by predators and the environment. When the hickory bark beetle is climbing along the bark of a tree its elytra appear to form a solid covering, but actually each elytrum is able to lift when the hickory bark beetle takes to the air.
The hickory bark beetle feeds mostly on the sap and bark of hickory trees. It bites and chews its food with its strong, powerful mandibles, or jaws, and then pushes its food into its throat with its maxillae and its lips.
Mating season for the hickory bark beetle takes place during the spring when the weather turns warm. Pairs of hickory bark beetles mate in the trees, and then female hickory bark beetles lay their 20 to 60 eggs in the wood of the hickory bark.
After a developmental stage within the eggs, young hickory bark beetles hatch as larval beetles. At this stage the hickory bark beetles are worm-like and pale. They spend most of their time feeding and molting, or shedding, their skins. Each hickory bark beetle grows with each molt. Eventually, the hickory bark beetle larvae move into the bark to pupate. They molt from their larval forms into a growth stage in which they develop their wings. From this stage, the hickory bark beetle pupae emerge as adult hickory bark beetles.
Birds, wasps, and flies are some of the many predators of the hickory bark beetle which is also often threatened by parasites. The life span of the hickory bark beetle is between one and two years. The hickory bark beetle is not a threatened species.
Bibliography
Juzwik, Jennifer. “Hickory Bark Beetle: Scolytus Quadrispinosus - Curculionidae (Snout Beetle).” Midwest Invasive Species Network, 2024, www.misin.msu.edu/facts/detail/?project=misin&id=244&cname=Hickory%20bark%20beetle. Accessed 5 Apr. 2024.
Waliszewska, Aleksandra. “Species Scolytus Quadrispinosus - Hickory Bark Beetle.” Bug Guide, 2024, bugguide.net/node/view/122189. Accessed 5 Apr. 2024.