Southwestern Pine Beetle
| Authors: | Demian F. Gomez, Jackson P. Audley, Christopher J. Fettig |
| Year: | 2025 |
| Type: | Scientific Journal |
| Station: | Pacific Southwest Research Station |
| Source: | Forest Insect and Disease Leaflet No 192. |
Abstract
The southwestern pine beetle, Dendroctonus barberi Hopkins (Coleoptera: Curculionidae: Scolytinae), is a significant pest of ponderosa pine (Pinus ponderosa) in the Southwestern United States. Pinyon pine (Pinus edulis) and Douglas-fir (Pseudotsuga menziesii var. glauca) have also been recorded as occasional hosts. The southwestern pine beetle occurs in Arizona, Colorado, New Mexico, Nevada, Utah, and Texas, and in the Mexican States of Chihuahua, Coahuila, Durango, Nuevo Leon, and Tamaulipas. Its largest impacts occur in Arizona, New Mexico, and Texas.
Southwestern pine beetles play a vital role in forest ecosystems by shaping the structure, composition, and function of these environments. They often contribute to tree mortality in forests that are overly dense, overmature, or both. Trees weakened by factors such as drought, fire, lightning, or mechanical damage are particularly susceptible to infestation. At endemic (low) population levels, the southwestern pine beetle fulfills an essential ecological role by promoting forest health and renewal. At epidemic (outbreak) population levels, large numbers of trees may be killed, impacting many ecosystem services and causing severe economic losses. Dense stands of ponderosa pine, particularly those with 8- to 20-inch (20- to 50-cm) diameters at breast height (DBH), are especially susceptible to infestation.