Mountain pine beetle: what the agencies record

This page describes what the named sources say. It is not a diagnosis of any tree and does not say what should be done with one. Mountain pine beetle (Dendroctonus ponderosae) is native to western North America, and none of the pages below lists it as a pest that must be reported. Each section names its source, all read on October 8, 2026. The parent page, insect pests of trees, compares it with the other pests on the list.

Names

Natural Resources Canada, called NRCan, gives the scientific name Dendroctonus ponderosae Hopkins and the French name dendroctone du pin ponderosa. The British Columbia government and the Colorado State Forest Service both use the name mountain pine beetle and the same scientific name.

What the sources say to look for

The NRCan mountain pine beetle fact sheet says attacked trees are first detectable only from the ground, and that identifying symptoms needs close examination. It names boring dust and resin on the bark as the first signs, with the beetle positively identified only by looking under the bark. It describes pitch tubes that may last more than a year, woodpecker bark stripping, grayish blue staining of the sapwood from the blue stain fungi the beetle carries, and foliage that fades from bright to dull green and then turns brick red the spring after attack.

The British Columbia government's mountain pine beetle page (last updated March 26, 2026) lists reddish boring dust at the base of attacked trees, bark removal by woodpeckers, and soft white or reddish pitch tubes around each bore hole. It says foliage turns yellow and then red by the spring after the initial attack and that most needles drop after two years, leaving a dead grey snag. It points to the Field Guide to Forest Damage in B.C. for identification.

Hosts

NRCan says most pine species, including some exotic ones, are attacked, with Jeffrey pine not a suitable host, and that lodgepole, ponderosa and whitebark pine are the most common hosts in British Columbia. It adds that Engelmann spruce is occasionally attacked during outbreaks but beetle populations do not persist there, and that jack pine is a suitable host. The British Columbia page calls large, mature lodgepole pine by far the most commonly affected, with western white, whitebark and ponderosa pine also attacked, and says the beetle prefers trees more than 80 years old. The Colorado State Forest Service names lodgepole and ponderosa pine.

Life cycle as the sources state it

NRCan says the life cycle normally lasts one year. Adults emerge between July and September, females bore vertical galleries under the bark and lay eggs, and the larvae feed under the bark over winter. It says the beetle carries blue stain fungi that together with the beetle are believed to stop water transport and kill trees. The British Columbia page gives a one-year cycle with colder climates sometimes needing two, and says very cold winter weather kills the beetles and has historically kept numbers in check.

Where it is reported

Source	What the page says
NRCan	Present in most lodgepole pine forests of British Columbia, adjacent, central and northern Alberta, and isolated locations in southwestern Saskatchewan, with the range expanding northward and eastward.
British Columbia government	Found throughout the range of its host pines. It describes a massive outbreak in the late 1990s after several relatively warm winters, with the loss of millions of hectares of pine forest over the next 15 years.
Colorado State Forest Service	From the late 1990s through 2013 the beetle affected 3.4 million acres of forests in Colorado, mostly lodgepole pine, and killed up to 80 to 90 percent of trees in some lodgepole forests in four named counties.

Regulated status and who takes a report

None of the three pages describes an order, quarantine or reporting duty for this native beetle. For the pests that agencies do ask people to report, see Canada and the United States.

What the sources say about moving wood and management

The Colorado State Forest Service has a management section on strategies for managing trees and disposing of infested wood; this profile does not repeat it. For wood movement rules by place, see moving wood and firewood. NRCan says natural enemies, including insect predators, parasitoids and woodpeckers, do not have enough impact on starting or outbreak populations to give effective control, and that aerial surveys followed by ground inspection are used to find attacked stands. This page gives no product names, rates or timings. For who may apply pesticides, see pesticide licences.