261A
Klamath Mountains

M261B
Northern California Coast Ranges
Location map, M261A and M261B

Ecology

The Klamath Mountains and the Northern California Coast Ranges sections share at least three vegetation categories: montane forest, mixed evergreen, and montane chaparral. The Northern Coast Ranges are slightly drier than the Klamath Mountains, which may account for why blue oak and gray pine are more common in M261B. Tree species common to both sections are Douglas-fir, ponderosa pine, white fir, Port-Orford-cedar, sugar pine, Pacific madrone, canyon live oak, tanoak, Oregon white oak, California black oak, and bigleaf maple. Red fir, mountain hemlock, Jeffrey pine, incense-cedar, and western white pine are more common in the Klamath Mountains.

Forest Health Issues

California black oak. Black oaks along many drainages were defoliated by septoria leaf blight, but damage to the trees was minimal. Trees are defoliated sporadically when temperature and moisture conditions in the spring are conducive to infection. This type of defoliation may not significantly affect forest health, but can influence public perceptions because of its visibility.

Douglas-fir. Black stain root disease is commonly observed on small Douglas-firs, especially along roads. Evidence that the disease is causing decline and mortality of larger Douglas-firs is increasing, however; although not always apparent, some form of past disturbance is usually associated with the decline. Whether the disease is actually increasing or only being better recognized is unknown. If it is increasing, management activities may be causing the increase.

Drought has caused Douglas-firs in some overstocked stands to be quite susceptible to the Douglas-fir beetle and the flatheaded fir borer. Douglas-fir dwarf mistletoe is often a factor in the mortality. Mortality associated with these beetles is higher than has been seen in recent years, but it is still low compared with the more ubiquitous pine bark beetles.

Incense-cedar. Incense-cedars are generally hardy, with few aggressive insects or pathogens that attack them. During the last few years, however, incense-cedars have been declining and dying over a wide area. All sizes of trees are affected, but most of the damage has been in smaller trees. The majority of this damage has been on low-quality sites with dense vegetation. Some bark beetles were identified in these trees, but the underlying cause of damage is drought.

Pacific madrone. Pacific madrone suffered a foliage blight along the Klamath and Trinity River drainages in 1994 and, to a lesser extent, in 1995. During the spring of 1994, the bare reddish-brown stems of Pacific madrone were evident on the slopes because of defoliation. Several fungi were involved; the most common was Coccomyces arbutifolius. The trees refoliated after bud break, but the blight continued through 1995. Damage was limited to branch dieback and some tree mortality.

Ponderosa pine. Ponderosa pine mortality was higher than normal in many areas of the section as a result of drought and bark beetles and engravers (fig. 17). The beetles contributing to the mortality included the western pine beetle, pine engravers, red turpentine beetle and, to a lesser extent, the mountain pine beetle. Areas where ponderosa pine mortality was prevalent included the major river corridors, such as the Sacramento and Trinity Rivers, and also around large valleys. The lower elevation valleys receive less precipitation than do the surrounding mountains. Outside of the major valleys, particularly in the Northern Coast Ranges, the most common pattern of pine mortality was large areas with scattered dead trees.

Tree mortality in the Klamath mountains
Figure 17 — Aerially surveyed tree mortality in the Klamath Mountains, 1994 and 1995.
 

Port-Orford-cedar. Port-Orford-cedar root disease is still the most significant concern affecting the health of the species. In 1994 and 1995, additional locations of this disease were identified in previously uninfested tributaries of the Smith River. Spread of this root disease is expected to continue in infested areas because of the limited ability to control access to all areas.

In 1995, the disease was confirmed in a tributary of the Klamath River. This identification is the first in a native stand in California outside the Smith River drainage. The site of infection is several miles from the Klamath River confluence, but the tree species grows along the entire tributary system leading to the river. This infection puts downstream Port-Orford-cedar at risk in this watershed. It also increases the risk of transporting the pathogen into watersheds farther up the Klamath River.

Red fir. Dwarf mistletoe infections of red fir are moderate to high in many locations, and cytospora canker is common in the branches of red fir, especially in areas with dwarf mistletoe. These two agents reduce the amount of live branches in trees and weaken them. The weakness, combined with drought stress, increased successful attacks by the flatheaded fir borer and tree mortality. As a result, red fir continues to decline and die in many areas (fig. 17), particularly in old-growth stands.

White fir. Concentrated white fir mortality was observed in the Taylor/Carter Meadows Late-Successional Reserve on the Klamath National Forest. Extended drought and attacks by the fir engraver were responsible for the mortality. Damage has been so severe that an analysis was necessary to determine whether conditions had shifted outside the natural range of variability of late-successional reserves.

White pine. White pines in this section include sugar pine, western white pine, foxtail pine, and whitebark pine. Foxtail and whitebark grow near timberline on the highest mountain peaks. White pine blister rust is common throughout much of the section; it arrived in the 1930s and 1940s. Most of the damage is to sugar pine, but western white pine is becoming increasingly affected. Limited surveys of the two high-elevation species found light infection by blister rust. Damage by this fungus is not currently affecting survival of either foxtail or whitebark pine in the Klamath Mountains.

Sugar pine mortality caused by drought and mountain pine beetle increased in 1994. Both large, overstory trees and visibly vigorous 20 to 80-year-old trees were killed. Sugar pine mortality continued at a high rate during 1995, particularly on the Six Rivers National Forest and the western part of the Klamath National Forest. The most common pattern of mortality in the Northern Coast Ranges was large areas with scattered dead sugar pines.

Current Forest Health Activities

Permanent and seasonal road closure is a primary means of preventing spread of Port-Orford-cedar root disease. Soil that may contain the fungus is washed from vehicles and equipment before they enter and work in uninfected areas. Seedlings from more than 300 parent trees are being screened for potential resistance to the root disease. If resistant trees are identified, they will be protected, and the seed will be collected for future regeneration. Training and information activities are increasing public awareness of how to prevent spreading the disease.

In 1995, the Klamath National Forest began evaluating the Taylor/Carter Meadows Late-Successional Reserve in response to the severity of white fir mortality from 1993 to 1995. The goal in late-successional reserves is to protect and enhance conditions of late-successional and old-growth forest ecosystems, which serve as habitat for species dependent on old-growth, including the northern spotted owl. These conditions may have been compromised by the mortality of white fir.

The Salmon River District, Klamath National Forest, sprayed three rust-resistant sugar pines with carbaryl in 1995 to protect them from bark beetle attacks. Numerous attacks on sugar pines, including those near the resistant pines, put the trees at risk. All three of the sprayed trees survived.

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