"It's happening all the way around the lake," says Paul Henry Abram, who moved to the lakefront community 18 months ago from Hanford. "It's going to probably get 10 times as bad. ... A lot of [trees] are just absolutely brown."

Skip Howard of the Sierra National Forest peels back the bark of a dying ponderosa pine tree near Bass Lake, looking for evidence of the beetle infestation that is killing hundreds of trees in the area. (Photo by John Walker / The Fresno Bee)

The quarter-inch-long beetles are a large problem, threatening hundreds of the tall trees in the federally managed Sierra National Forest.

The primary culprits are the western pine beetle and the ips beetle. After they have turned green, healthy trees into brown, sickly ones, mountain turpentine beetles arrive to share in the feast. And when the beetles are finished, so are the trees.

The beetles have affected "a few hundred trees" in the area around North Fork, Oakhurst and Bass Lake, says district ranger Dave Martin in the North Fork office of the Forest Service.

The beetles take out a section of trees by destroying one tree and moving to the next.

The beetle infestation runs in cycles of eight to 10 years. Long, hot summers increase the beetle population, and drought limits pines from making sap, a natural defense against the pest.

Trees can better combat the beetles if they have more ground water to produce more sap, officials said.

In the meantime, Abram says, the Forest Service needs to attack the insects with sprays and treat some trees with Vitamin B, which has been successful in battling the pests in other areas.

Sierra National Forest has no money to battle the beetles -- either forestwide or one tree at a time. For now, federal officials are watching and waiting for nature to ease the problem.

But Abram is concerned that without federal intervention, the infested trees are being allowed to die so they can be sold for logging. The 61-year-old lawyer estimates that hundreds of trees around the lake are affected.

Abram adds that the infested trees could lead to widespread salvage logging, and new roads through the forest.

"It's not a very conservationist program," Abram says.

Martin says the beetle-infested, dead trees are fuel for faster-burning and hotter wildfires. Some of the area's trees are marked for sale to commercial loggers.

"The pockets of trees that we've identified ... roads won't be needed for any of these," Martin says of commercial logging. "There will be some minimal amounts of logging to take care of many of these."

Along Road 274, a giant osprey perches with its nest atop a dead pine. But other dead trees near lakeshore roads or power lines are marked for early removal.

Nearby, Forest Service workers have painted blue bands around the trunks of two tall but brown trees. They are close to power lines and will be cut before they can fall across the lines and spark a forest fire.

Madera County Supervisor Gary Gilbert can see some of the infested trees from his North Fork home. Gilbert, a retired California Department of Forestry chief and former Madera County fire chief, says the dead trees can fuel intense forest fires.

Natural fire is part of the ecosystem. Historically, low-intensity flames have cleansed the forest of dead trees and thick underbrush. Forest fires also kill insects.

But a century-old policy of dousing all wildland fires and the continuing construction of homes, shopping centers and resorts in mountain communities have added to the potential for danger.

Deliberate burning of dead trees such as those in the Sierra National Forest could quickly sweep out of control through underbrush grown thick after decades without cleansing, low-intensity fires.

"Where these trees are grouped and it's economical, they should be logged," Gilbert says about the dry pines.

The reporter can be reached at cmcarthy@fresnobee.com or (559) 675-6804.