Are our ponderosas dying?

By Chris McGinnis

Many mountain subdivisions, rural acreages, and homes in Buena Vista and Salida are enhanced by mature, magnificent, pine trees.

However, these trees, particularly local pondersosa pines, are in the midst of a parasitic beetle attack, which left untreated, can kill pines throughout Chaffee County.

Mountain pine beetles develop in ponderosa, lodgepole, Scotch and limber pines.

A stand or single dead tree killed by the beetle may be unsightly, but that's not the only problem in leaving trees untreated.

One infected tree can produce enough beetles to infect as many as eight to 10 trees in the surrounding area the next year. Because of this, dead, brown stands of the beetle- infected trees are visible throughout the county from the road, trail or home.

"Once mountain pine beetle infest a tree, nothing practical can be done to save that particular tree," entomologists David Leatherman and Whitney Cranshaw from the Colorado State Forest Service wrote in a newsletter available through the forest service office in Salida.

"Mountain pine beetle is the most important insect pest of Colorado's pine forests. MPB often kill large numbers of trees annually during outbreaks," the scientists report.

"Outbreaks develop irrespective of property lines, being equally evident in wilderness areas, mountain subdivisions and back yards. Even pines many miles form the mountains can succumb to beetles imported in infested firewood."

The dead stands also present a fire hazard - should a lightning strike or errant campfire get in the midst of such a stand, the wood would serve as an excellent catalyst for a forest fire.

Are my trees infected?

How does a property owner identify whether trees have pine beetle? A few of the signs on a tree are:

- Popcorn- shaped masses of resin, called 'pitch-tubes' on the trunk where beetle tunneling begins.

Pitch tubes are brown, white, yellow or reddish in color.

- Boring dust in bark crevices and on the ground immediately adjacent to the tree base.

-Evidence of woodpeckers feeding on the trunk. Woodpeckers feed on the beetles in the tree.

- Needles (foliage) on the tree turning yellowish to reddish brown throughout the entire tree crown. This usually occurs eight to 10 months after a successful MPB attack.

- Presence of eggs, larvae, pupae and/ or adults, as well as galleries under bark. This is the most certain indicator of infestation. A hatchet for removing bark is needed to check trees correctly.

-Wood has a blue stain at more than one point around the tree's circumference.

My trees are infected, what can I do?

The old saying, "A stitch in time saves nine," applies to beetle treatment. If you believe you have mountain pine beetle, taking action to control the infestation is important.

While you will have to cut down your tree or trees for treatment, you will likely prevent the future loss of many more trees.

During a pine beetle cycle, yearly monitoring and treatment is required. Recommended action taken between winter months and June 1 of each year for infected trees by the Colorado Forest Service:

- Cut and burn the tree.

- Cut, block into firewood lengths, stack, soak with water, cover with plastic. Mold will develop which will inhibit development of MPB. Keep plastic in place until mid- August.

- Cut, remove all limbs, place logs in an area where they will receive a maximum amount of sunlight. Do not stack logs or place them within 2-3 feet of each other. Rotate logs each month to expose all sides. Continue rotating logs until mid- August.

- Cut and haul wood to a site not closer than three miles to the nearest ponderosa pine trees. This distance requirement limits this option in our area.

- Cut, buck into rollable lengths and spray all bark surfaces with a Lindane chemical formulation. Follow all label directions.

What can I do to prevent future attack?

- The state forest service suggests yearly spraying of high value trees with a Sevin chemical formulation to kill beetles. Trees must be thoroughly sprayed up to a four- inch top.

- Long - term, thin trees on your property to promote a healthy, vigorous stand which will withstand disease.

- Studies by entomologists continue on possible treatment of the mountain pine beetle.

Wendy Fischer of the State Forest Service office in Salida, said there is some evidence the beetle is in the midst of a 10- year infection cycle, the peak of which could occur this year.

Originally, mountain pine beetle was common around the Chalk Cliffs area. The infestation now encompasses an area from Twin Lakes to Monarch Pass, Fischer said.

Conditions have been right for a spread in infestation, she added. Little forestry management has taken place in Chaffee County. Local tree stands are stressed by drought, injury, and damage during growth from conditions such as overcrowding. All combine to make the trees, susceptible to infestation, Fischer said.

The Colorado State Forest Service has contracted with a number of subdivision representatives and property owners to mark trees, Fischer said. The Forest Service can also recommend people for preventative spraying of live trees or removal of dead trees, she said.

For more information on the pine beetle, contact the Colorado State Forest Service, 7980 Hwy. 50 W. Salida, (719) 539-2579.