CABLEWAY TREE ANCHORS AND POSSIBLE PROBLEMS

ROBERT MEYER

Use of a cableway with a tree anchor that would be classified as very poor, poor or hazardous is prohibited.

The six photographs show conifer trees in various conditions. If any cableways are anchored to a tree that is in a less-than-good category (based on photos), it should be considered hazardous. Any classed as very poor are an immediate hazard. Others should be inspected by a forester.

A healthy conifer in very good condition.

This picture shows a conifer in good condition

The conifer on the left is in good condition and the one on the right is in poor condition

This conifer is in fair condition.

This picture shows a tree in poor condition.

A conifer in very poor condition.

The following are simple guidelines (visual indicators) for evaluating the risk of tree mortality and/or breakage, for various tree species. If any of these conditions are observed, the risk of mortality (or catastrophic failure) is increased.

Large, abnormal swellings, running sores or wounds. If the cable penetrated the bark, i.e. it's overgrown, this wound site could easily allow disease organism to enter. It also makes inspection of the cable difficult or impossible. If large areas of trunk are involved, consider this a hazard.
Large, basal wounds caused by fire (so-called "goose-pens"). This may be considered a hazard, and requires further inspection.
Large amounts of mistletoe, covering more than 15% of crown. This infestation is often called "witches broom". If more than 15% is covered, this may indicate a severely weakened tree, susceptible to attack by beetles or disease. Consider this condition hazardous.
Fruiting bodies of fungal diseases. Photos of several of the deadly types are shown here. The "bodies" are often called "conks"; some look like mushrooms. If you confirm the presence of such disease, consider this condition hazardous. It should have a professional evaluation (some fruiting bodies of relatively benign organisms are similar in appearance to deadly ones).
Strong curvature of the tree trunk near the base, a direct indicator of slope failure due to soil creep. This could become an active slide site at any time if sufficient lubrication (rainfall) occurs. Consider this condition hazardous.

If the cable is anchored to an oak tree, this may be hazardous. Oaks are highly susceptible to heart rot, with poor indicators for identification. Oaks, especially large, old ones, may suffer catastrophic failure at anytime. If the cable installation has damaged the trunk, disease has probably entered the wound(s). If any doubt, tree should be inspected by professional.

In all cases, Digger pine (also called "Gray Pine" or "Bull Pine") - Pinus sabiniana should not be used.

Figures 2 and 3 show the various fruiting bodies of several serious fungal diseases that attack trees in California and the Pacific Northwest. A thorough visual inspection of all trees used as anchors, using binoculars, is recommended. Also look carefully at the ground around the tree for "mushrooms" of the type shown. If you have any tree anchors that appear to have any of the conditions shown in figure 2 or 3, THE CABLEWAY SHOULD NOT BE USED. An inspection by a knowledgeable person is required before allowing further use. Replacement of the anchor blocks is highly recommended for any suspicious tree anchor.

Quinine Fungus Fomes officinalis; enters through wounds, fire scars, broken tops. Often only one fruiting body occurs. Affects main trunk, making tree susceptible to breakage.

(photo not available)

Laminated root rot: affects fir and cedar. Attacks roots, leaving them structurally weak, susceptible to windthrow.

Velvet top fungus: may appear in or on the soil near a tree, or on the lower 10 feet of trunk. It has a velvety appearance and feel, dark brown. Mortality nears 100% from this fungus. Trees very susceptible to windthrow.

Armillaria root disease: attacks conifers and oaks, common in Northern California. It attacks roots, leaving tree structurally weakened, very susceptible to windthrow. The mushroom like fruiting bodies develop around the base of infected trees.

(photo not available)

Pocket dry rot: affects mostly cedar, especially large, older trees. Results in extensive heart rot. Severely weakens the structural integrity of a tree, susceptible to breakage. Usually few or one fruiting body.

Mistltoe (phoradendron): heavy infestations seriously weaken a tree, making it susceptible to attack by other organisms.

It would be a good idea to inspect all large trees that could fall onto the cable. A once-a-year visual inspection, during the cableway inspection could be a good form of insurance. An hour or two of inspection could save a life! In some areas, if a tree creates a hazard, we might be able to have them removed, or be encouraged to move the cableway.

If you identify an anchor tree, or a tree that could fall on the cable as being suspicious, I am willing to visit the site and thoroughly inspect the questionable trees (I have a degree in forestry, and have been a certified timber cruiser).

Robert W. Meyer
Hydrologist: USGS
California District: Quality Assurance Group

A healthy conifer in very good condition.	This picture shows a conifer in good condition
The conifer on the left is in good condition and the one on the right is in poor condition	This conifer is in fair condition.
This picture shows a tree in poor condition.	A conifer in very poor condition.

	Quinine Fungus Fomes officinalis; enters through wounds, fire scars, broken tops. Often only one fruiting body occurs. Affects main trunk, making tree susceptible to breakage.
(photo not available)	Laminated root rot: affects fir and cedar. Attacks roots, leaving them structurally weak, susceptible to windthrow.
	Velvet top fungus: may appear in or on the soil near a tree, or on the lower 10 feet of trunk. It has a velvety appearance and feel, dark brown. Mortality nears 100% from this fungus. Trees very susceptible to windthrow.
	Armillaria root disease: attacks conifers and oaks, common in Northern California. It attacks roots, leaving tree structurally weakened, very susceptible to windthrow. The mushroom like fruiting bodies develop around the base of infected trees.
(photo not available)	Pocket dry rot: affects mostly cedar, especially large, older trees. Results in extensive heart rot. Severely weakens the structural integrity of a tree, susceptible to breakage. Usually few or one fruiting body.
	Mistltoe (phoradendron): heavy infestations seriously weaken a tree, making it susceptible to attack by other organisms.