Common Pine trees in our area

 

Austrian, Lodgepole, Scotch, Limber, White, and Pondersosa

 

leaf

 

  • Many of our Pine trees have been attacked by many different insects and diseases. Instead of determining which Pine you have, realize that they all are subject to the folllowing problems, and treatment options all are about the same for all Pine trees.

 

Our Common Insects and Diseases

 

Mountain Pine Beetle Blackhorned Pine Borer Turpentine Beetle IPS Engraver

aphids

    Mountain Pine Beetles are the most destructive insect pest of Montana’s pine forests. Beetles have been identified within our city limits killing our Pines as well as some mature Spruce that get in the way. These beetles can kill large numbers of trees annually during outbreaks. The adult is about 1/8".

    Trees most likely to be attacked are not growing vigorously due to old age, crowding, poor growing conditions, drought, fire, mechanical damage, or root disease

As beetle populations increase, most large mature Pines in the outbreak area will be at risk causing even the healthier more vigorous Pines vulnerable to MPB attacks.

A bluish-black beetle, about 15 mm inch long with antennae the same length as the body. The wing covers are more leathery than those of other beetles and the body form is rather flattened. Larvae, found within wood, resemble most roundheaded wood borers, being off-white, elongate legless grubs with brown heads.

Damages live Pine trees under severe stress

This borer also may cause concern to home owners when adult beetles emerge from firewood or unseasoned lumber. Also, large amounts of sawdust can be produced and expelled by the larvae developing in fire wood, producing concerns about potential harm to household items.

Adults are reddish-brown about 3/8" in length, the largest of the Dendroctonus bark beetles. Larvae are up to 1/2" in length, and feed together in a common brood chamber. Pupal chambers may be found at the base of the host tree.

Red turpentine beetles commonly attack trees already weakened by injury, other bark beetle attacks, or disease. Freshly cut stumps, exposed roots and the lower trunk of declining trees are all attacked, as are "leave" trees after logging operations and fire survivors. It is commonly associated with attacks of Ips or mountain pine beetle, which are usually responsible for the actual death of the tree.

Ips beetles are small (1/8 to 3/8 inch long), reddish-brown to black beetles.

Unlike mountain pine beetle, infestation by Ips beetles does not necessarily mean the whole tree will die, but over time, attacks may progress as later generations “fill” the tree and then ultimately the host can die.

As adult Ips beetles enter trees and tunnel, a yellowish- or reddish-brown boring dust is produced and accumulates in bark crevices or around the base of the tree.
TREATMENT  TREATMENT TREATMENT TREATMENT

 

More Insects & Disease

Pine Needle Scale White Pine Weevil Zimmerman Moth Diplodia Tip blight
canker3

White females are about 3 mm long.

Scale insects feed on plant sap. They have long, threadlike mouthparts (stylets) six to eight times longer than the insect itself. Feeding by scales slowly reduces plant vigor. Heavily infested plants grow poorly and may suffer dieback of twigs and branches. Occasionally, an infested host will be so weakened that it dies. 

The adult is a small rust-colored weevil that is about 4-6 mm long. It has irregularly shaped patches of brown and white scales on the front wings.

This species kills the terminal leader primarily of eastern white pine. Colorado blue spruce, Norway spruce, Scots, red, pitch, jack, and Austrian pines, and occasionally Douglas fir are also attacked. Trees become susceptible to injury when they reach a height of about three feet.

Adults spend the winter in the leaf litter under or near host trees. On warm spring days they fly or crawl to the leaders of suitable hosts usually during the period from mid-March through April.

The adults, rarely observed, are midsized moths, with gray wings blended with red-brown and marked with zigzag lines. Larvae are generally dirty white caterpillars, occasionally with some pink or green.

They are found within the characteristic popcorn-like masses of sap on the trunks and branches. Branches typically break at the crotch area where they join the trunk. Dead and dying branches, most often in the upper half of the tree, commonly indicate infestations.

This disease is most commonly seen on Austrian and black pines and some of the other two-and three-needle pines such as red pine, Mugho pine and Scots pine. It is found more uncommonly on white pine, spruces and other evergreens. The fungus commonly attacks mature trees that have been under stress from drought, root restriction or other planting site problems.

Other problems can cause similar dieback and tree decline. Winter drying, drought, injury from weevils, pine-shoot moths or tip moths, as well as some needlecast diseases caused by other fungi may cause damage similar in appearance to tip blight.
TREATMENT TREATMENT TREATMENT TREATMENT

 

 

Precautions

Keep your Pines fertilized and watered to reduce the chances of insects or diseases from attacking them. If they are attacked and it is too late to do anything about it, it is very important to remove the tree as soon as possible to avoid spreading the insect or disease to your other trees. Remember Pines that look a little red or brown in the top and have many pitch tubes from attack are already dead, the needles just haven't dried out yet.