More than one-tenth of Iran is forested. Mild climate, plentiful rainfall, and a long growing season have combined to make a dense forest of high-quality timber in the Caspian region. Moreover, more than 2,000 plant species are grown in Iran. There is an extensive growth of temperate-zone hardwoods, including beech, oak, Siberian elm, maple, walnut, ash, ironwood, basswood, alder, and fig. About half of the Caspian forests consist of these trees; the remainder is low-grade scrub. The Zagros Mountains in the west and areas in Khorasan and Fars provinces abound in oak, walnut, and maple trees. Shiraz is renowned for its cypresses.
Nature of Iranian Forests
The Iranian forests belong to the European-Siberian growth region in the Holarctic. This region includes parts of Europe and Northern Asia of which the climate varies from cold to moderately warm weather. With regard to flora, this area could be divided into the sub-regions of Northern, Atlantic, Pontic, and Central Europe.
The Pontic sub-region in the Middle East is represented by Accino-Hircnai Province. This sub-region includes the northern slopes of the Alborz Mountains and the coastal areas in its vicinity, and northern Turkey’s mountains. This is well adapted for
the expansion and growth of forests. The annual rainfall of this area is more than 1,000 mm. Also a part of this region enjoys summer rainfall. The flora of this area consists of 8% Iranian-Turanian, 22% Mediterranean- European-Siberian, and 40% European-Siberian species.
One of the most distinct features of this area is its appropriate environment for those types of flora that were in danger in Europe at the expansion stage of cold weather in the later years of the Neogene Period (theThird Period). This group of flora expanded quickly in this area and became part of the endemic species. There are other sub-provinces named the Hyrcanica. It enjoys a variety of tree species; however it has less richness divided into three groups: One of them is the Alnetea Hyrcanica, which includes different species such as the forests of the Caspian coastal area.
Iranian forests can be classified ecologically as comprising of these biomes:
Caspian broadleaf deciduous forests
The important species of trees on commercially usable forests are:
Beech Fagus orientalis
Hornbeam Carpinus betulus
Oak Quercus castaneifolia
Alder Alnus subcordata
Maple Acer velutinum
Linden Tilia caucasica
Persian iron wood Parrotia persica
Forest Distribution and Specifications
The entirety of the southern and southwestern areas as well as parts of the eastern regions of the Gorgan plain is covered with forest, totaling an area of 421,373 ha in 1998. There are three forest parks totaling 1,224 ha and there are 2,930 ha of artificial forests. The total production from these forests is estimated at 269,022 cubic meters.
The total area of the forest in this province is estimated at 965,000 ha which is mainly comprised of broad leaf trees. The forests in the eastern part of the province are connected to the Minoodasht and Golestan forests, and are distributed at two
major regions, Sari (645,000 ha) and Nowshahr (320,000 ha).
From these forests, 487,195 ha are used commercially, 184,000 ha are protected and the rest are regarded as forest lands or over-used forests. There are 11 forest parks totaling an area of 5,494 ha and 29,877 ha of artificial forests.
There were 567,524 ha of forests in Gilan province in 1998 out of which, the Astara area with about 80,000 ha ranks first in the region. These forests are graded 1-2-3 with an area of 107,894; 182,758
and 211,972 ha respectively.
The area of artificial forests in 1998 was estimated at 1,062 ha, there are also 16 forest parks totaling 5,394 ha, and 5 forest biospheres totaling 2,373 ha.
The commercial and non-commercial utilization is 310,375 cubic meters (184,202 cubic meters for commercial and 126,173 cubic meters for non-commercial use).
According to an estimate made by the Forest and Range Lands Organization, the total area of the Caspian forest in 1963 was 3,420,487 ha. In 1980, a new inventory was made which estimated the total forest area at 1,900,000 ha. During the last 13 years, there has been a continuing degradation of forest area, so much so that today the total area of the Caspian forest is approximately 1,800,000 hectares. If the areas that receive more than 500 mm of precipitation were considered forests, the total area would be about 3,600,000 ha.
In addition to dimensional degradation, the forest’s standing crop or biomass is also being destroyed. Before destructive exploitation, the average biomass of the Caspian forest was about 300 tons per ha. Today the average is less than100 tons per ha. In altitudes lower than 600 meters, the areas have been almost completely cleared of valuable timber. The situation is similar in high altitudes where the inhabitants of sub-alpine pastoral areas have devastated the sub-alpine forests by selective removal and later by complete removal of vegetation.