Environment: Turning Green into Yellow

One-third of West Germany's precious forests are dying off

Surveying row upon row of scrawny, sagging firs and spruces, Forester Hubert Eh threw up his hands in despair. "We were always so proud of these trees," said Eh. "Now the Black Forest is becom ing the Yellow Forest. It's enough to make you cry."

Eh's domain lies near the resort village of Herrenalb in the southern German state of Baden-Württemberg. In the hills above the quaint Black Forest town, the dark evergreens that gave the region its name are dying, victims of a blight that is destroying an alarming amount of the for est acreage of heavily industrialized West Germany. In the central state of Hesse, 10% of the spruce are now gone; in the northern city-state of Hamburg, almost 25% of the pines are suffering. Southern Germany has been hit most severely: more than half the trees in the 2,300-sq.-mi. Black and 1,800-sq.-mi. Bavarian for ests are damaged, and the devastation is spreading. Last year, according to the Interior Ministry in Bonn, only 8% of the nation's forests were afflicted. This year the figure has leaped to 34%. The situation in East German forests is reported to be even worse.

The signs of what Germans call Waldsterben, or dying forests, are obvious. New leaves and needles, smaller than usual, turn yellow or brown and finally drop to the ground. In time, many evergreens, some of them 150 years old, simply stop bearing needles. Roots and trunks begin to warp, gnarl and shrink.

Insects and mushrooms colonize the sick trees, hastening the plants' deaths. About 15% of West Germany's oaks and 26% of its beeches are ailing. But evergreens have been the most susceptible: 76% of the country's firs are affected.

The damage was first detected around 1970, but scientists suspect that the destruction be gan two decades earlier. One clue: cross sections of tree trunks show that their growth rings, widely separated for more than a century, began narrowing in the 1950s and '60s, a sign of impaired growth. Researchers initially blamed severe climatic conditions, like the near drought of 1976. Today suspicion focuses on environmental pollution, particularly the acid rain caused by auto and industrial emissions.

(West German industries burn 3.5 million tons of coal a year, leading to heavy discharges of sulfur dioxide.) According to Professor Bernhard Ulrich, an expert on soil science at the University of Gottingen, acidic downpours can leach key nutrients, such as calcium and potassium, from the soil, or deposit toxic metals like aluminum. Acid rain might also prevent microorganisms in the soil from converting organic debris into fertilizer. Professor Peter Schiitt of the University of Munich believes that dry, airborne particles of metal are the culprits, along with acid rain. Says he: "What is shocking is that whole areas are affected with such speed and that no one has a satisfactory explanation."