There is a concern about our high elevation spruce forests. Many observers have noted dead and dying Red Spruce on the Monongahela National Forest for some time. This is a review of three papers dealing with them.

In 1984 a U.S. Forest Service Plant Pathologist, Manfred Mielke, observed this phenomenon and reviewed air photos of the National Forest area where most of West Virginia’s spruce are found. He found Spruce on 110,685 acres within the National Forest boundary, and of this, he found light mortality in 86.5%; 5.7% was moderate, and 1.5% was heavy. (There was a last 6.5%, mostly on Cheat and Shavers Mountain, that did not photograph well.) He figured only 7% of the stands had a greater mortality than 10%. However 40% of the number of Spruce were dead or declining.

"Declining," an important value, was based primarily on crown vigor. It means a huge number, 1/3 of our Spruce volume is dead or declining. He notes Red Spruce should live 300 or more years. This then 80 year old forest is young.

This confirmed losses here that had been noted elsewhere throughout the Appalachians in other studies done at the time. In this study the dominant tallest spruce and those just below were counted, and most of the decline in the crowns was noted in those now crowded in the shade. This is normal forest dynamics, many foresters will tell you. This death is "natural" and not inordinately high at this stage and crowded circumstance. The explanations remain controversial today.¹

In 1996 Pennsylvania State foresters and the US Forest Service (USFS) sampled West Virginia Spruce again, and now our spruce were found to be in "good health." Only dominant and co-dominant trees were examined, again mostly for crown condition. These were not the declining smaller Spruce of the air-photo survey 10 years earlier. The recent study looked at only 351 trees (9 trees from each of 39 randomly selected stands) from Davis to Marlinton – about 1/3 as large a number as the earlier air photo study. Trees up to 261 years old were sampled. Only 10% appeared to be 10% declining. Of the 351 trees 63.8% of the trees were under 10% defoliated. The overall health was good.

The paper notes spruce drop shaded needles. They found the denser the stand and then the tighter the canopy closure, the more defoliation. They note these spruce had at least 4 year old needles, and that healthy spruce hold them from 4 to 7 years. The nutrient content of the needles, or soil acidity or nutrients, or lack of them, did not correlate with crown vigor.

Only 12 of the 39 stands sampled were not on "rough, stony land." This extensive land class is "strewn with rock fragments and massive boulders, with little or no soil in evidence -- the supply of plant nutrients, particularly phosphorus, are extremely limited." The other 12 are mostly soils "from sandstones or non-calcareous shales, with some bed rock near the surface and are generally limited in plant nutrients." They remark most nutrients are bound and recycled in the trees themselves and the forest floor. The soil had a pH of 4.05 (range 3.3 - 5.4). The forest floor humus had a pH of 3.64 (range 3.1 to 5.1). The available calcium, magnesium and potassium (exchange) were low.

Now a third study in 1998 in sampling spruce near Spruce Knob found , "annual growth rates in mature forests have stabilized after a period of decline that began around 1960 and lasted for 20-25 years.² The West Virginia Red Spruce forest occurs primarily above 3,000 feet, and was estimated to be less than 50,000 acres about 1990. They report they aged canopy dominant Spruce in 1995.

These authors recount that slowed tree growth was found in West Virginia and western Virginia spruce by Adams and Stephenson writing in 1985. [Dr. Stephenson is now at Fairmont State.] They had found very little growth from 1965 to 1981. The authors further recount this was found in other locations in the Appalachians and in New England too. They report also that air and ground surveys in the 1986 report by Mielke found declining and dead trees made up 33% of the total Red Spruce volume.

There was no evidence of past fires in this study near Spruce Knob. The stand ages were from 86 to 125 years old. The ages of the majority of the trees clustered tightly around the stand means, indicated all were started by a major disturbance. Back calculations place their logging at 1887 and 1908. The earlier disturbance in 1869 may predate the logging, escaping because the trees were small, being leveled by a previous disturbance. Growth in all stands was similar up to the 1930s, when growth rates began a period of increase that peaked in the late 1950s. In 1960 growth entered a general decline. From the peak 1959 rate they declined from 55 to 69%. Then in the mid-1980s growth rates increased and have been level or increasing since to 1994. They are levels that occurred in the 1930 to 1940 era. ³

These foresters note thinning of these dense stands should result in more growth and vigor for the remainder.

My comments follow:

These foresters have suggested thinning, and it might work in a limited way for a while. The "thinning" surely should not include a harvest where nutrients are trucked off-site. We must learn what percent of the total available nutrients would be trucked off. If it were 1/20, could this small amount be tolerated when the total nutrient capital is so small and continually declining by leaching by acid rain. A harvest should not be suggested with so little understanding of this unique, so valued, and acid perturbed ecosystem. During this 50-80 year history it has received perhaps 5 tons of Acid Rain per acre. Also we must add to this history that in the last 10 to 20 years the spruce ecosystem generally has become "nitrogen saturated" in a period of growth with reduced microbial activity complicating further our understanding of forest workings.

The fact that spruce on such infertile sites are in dense stands and making good growth is surprising in view of its ecosystem assault by Acid Rain. (Recent regrowth has been reported elsewhere in the Appalachians also.) No one knows why. We may have been gifted somehow with more hope for recovery if the environmental outrage of Acid Rain were removed from mountain tops throughout the Eastern Forest.

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¹ From Main to Georgia spruce mortality and decline has been observed. Regional acid rain has been suggested as a cause and recently how this would cause ecosystem stress has been elucidated. Very little growth of Spruce throughout its range had been found. Decline generally follows slow growth.

² Slowed tree growth occurred from Maine to Georgia within 5 years of 1965. This was 1/5 of the growth in the 1950s. As the authors of this third paper note slow growth persisted for 20 years. Now they report resumed growth, but is this forest health in light of increasing acidification and toxic aluminum in soil water and the leaching away of nutrients? The authors are Jim Hornbeck and Jim Kochenderfer, who is from The Fernow Experimental Forest at Parsons, W.V.

³ There is a history of acid rain that parallels and interacts with this tree growth history. This correlation has been pointed out by the USFS Researchers who knew of early work by Lunt in the 1920s. Since then, in the 1950s they found the spruce roots he studied had moved closer to the surface, in response to nutrients made available from the forest floor by the first of the regional acid rain. It was a pool of nutrients that were depleted generally throughout the Eastern Forest in the 1960s and growth throughout was found to nearly stop for 20 years. Being shallower, they were exposed more to drought, freezing and wind dislodgement.