LebEnv #19

TREES OF LEBANON: ALEPPO PINE

by Fareed Abou-Haidar

(Another installment of an occasional series highlighting the flora of Lebanon.)

Aleppo Pine, Pinus halepensis, is one of the most common trees of Lebanon and much of the Mediterranean. It has been around since antiquity and may have been the "fir tree" of the Old Testament. It grows on the lower mountains, perhaps up to about 1000 meters elevation, and reaches heights of up to ten meters. It lacks the symmetry of most other pine trees, as it does not have a well-defined, dominant growing tip and has many side branches of equal prominence. It is drought-resistant and can grow in poor soils and steep slopes. In Lebanon, it can be seen growing in thin soil and among rocks in areas that have been abused for centuries; perhaps it should be called a "band-aid" tree for growing in areas that most other trees stay away from, and for doing so at a fast growth rate.

Today, this tree covers extensive areas of Lebanon, including the Shouf and Aley areas and the steep mountains overlooking Jounieh. Along with shrubs and other vegetation, it forms a rich, green blanket on the mountains.

The Aleppo pine forests faces many threats, like all other natural features of Lebanon. The biggest three are:

• Urban sprawl: Construction of roads and buildings has destroyed many forests in the hills between Khaldeh on the coast and Bshamoun-Aramoun in the mountains, and around Jounieh.

• Fires: These trees are very vulnerable to forest fires because of their dense growth and low-lying branches. In the mid-1970s (I think it was 1974), most of the mountain overlooking Jounieh went up in flames; the fire was so big that the government sought help from outside the country. Only now have the new trees grown large enough so that the mountain looks green again. (At least what remains of it that has not been destroyed by the bulldozers...)

• Caterpillars: The Pine Processionary Moth, Thaumetopea wilkinsoni, is native to Cyprus but has been spreading across the Middle East since around 1940. These caterpillars (the larvae of moths) build silk-like nests in the tips of branches in early fall and work on defoliating trees of their needles. In late March, the caterpillars move in a procession to the ground and pupate for six months to emerge as moths and lay eggs. If trees are severely attacked over several years, they may die. Fortunately, new growth comes up in spring after the caterpillars have left the trees. The pest can be controlled by cutting the nests, spraying with chemicals (not desirable due to effects on other life forms) or, most preferable, spraying with Bacillus thuringiensis bacteria that paralyze the guts of the pests. The pests also have natural enemies in the form of various insects that attack eggs, larvae, and pupae. Birds apparently do not eat these hairy, poisonous caterpillars, which can cause dermatitis if they come in contact with humans. Cold, damp winters also limit the severity of attacks.

The Aleppo pine tree produces large quantities of resin for which it is sometimes tapped for. Fortunately, the resin makes it less desirable for firewood in a country where uncontrolled tree cutting took place during the war. In one village in the Souk el-Gharb area, hardwood oak trees, some over a century old, were cut for firewood by thoughtless individuals, but the pine trees, even large ones, were left alone. In fact, many parts of Lebanon are now greener than they were before the war! This can be explained by a lack of human activity in war-torn areas.

In Syria, large reforestation projects have taken place over the last few decades. Many of the trees are Aleppo pines. (Yes, they do grow near Aleppo, but do not reproduce well in the desert.) There is no reason why Lebanon cannot do the same. Although the tree often spreads naturally, much faster results can be obtained if barren areas and fire-damaged forests are actively replanted by people.