The character of the vegetation in Iran is determined by factors such as topography, elevation, water supply, and soil. Forests cover approximately one-tenth of the country, with the Caspian region having the most extensive forested areas. In this region, you can find a variety of broad-leaved deciduous trees including oak, beech, linden, elm, walnut, ash, and hornbeam, as well as a few broad-leaved evergreens. Thorny shrubs and ferns are also abundant.

The Zagros Mountains are home to scrub oak forests, along with elm, maple, hackberry, walnut, pear, and pistachio trees. Ravines in this area are filled with willow, poplar, and plane trees, as well as various species of creepers. On the intermediate dry plateau, you will find thin stands of juniper, almond, barberry, cotoneaster, and wild fruit trees. The steppes are covered by thorny shrubs, while medium elevations of the desert plains and rolling country are dominated by species of Artemisia (wormwood).

Below 3,000 feet (900 meters), you can find acacia, dwarf palm, kunar trees (of the genus Ziziphus), and scattered shrubs. Desert sand dunes, which retain water, support thickets of brush. Forests tend to follow the paths of surface or subterranean waters. Oases provide a habitat for vines and a variety of trees including tamarisk, poplar, date palm, myrtle, oleander, acacia, willow, elm, plum, and mulberry. Swamp areas are covered by reeds and grass, providing good pasture.

The country is home to a diverse range of wildlife, including leopards, bears, hyenas, wild boars, ibex, gazelles, and mouflons, which primarily inhabit the wooded mountains. Jackals and rabbits are commonly found in the country’s interior, while wild asses reside in the kavīrs. Cheetahs and pheasants can be found in the Caspian region, and partridges are distributed throughout most parts of the country. Aquatic birds such as seagulls, ducks, and geese inhabit the shores of the Caspian Sea and the Persian Gulf, while buzzards nest in the desert. Deer, hedgehogs, foxes, and 22 species of rodents thrive in semidesert, high-elevation regions. Palm squirrels and Asiatic black bears are specifically found in Baluchistan. Tigers, once present in the forests of the Caspian region, are now extinct.

Extensive studies conducted in Khūzestān province, the Baluchistan region, and along the slopes of the Elburz and Zagros mountains have revealed a remarkable variety of amphibians and reptiles, including toads, frogs, tortoises, lizards, salamanders, racers, rat snakes (Ptyas), cat snakes (Tarbophis fallax), and vipers.

The Persian Gulf is home to approximately 200 varieties of fish, as well as shrimps, lobsters, and turtles. The Caspian Sea, on the other hand, is home to the highly valued sturgeon, one of 30 species found there. Sturgeon plays a significant role in the country’s export income due to its production of caviar. Mountain trout are abundant in small streams at high elevations and in non-seasonal rivers.

To protect the country’s wildlife, the government has established wildlife sanctuaries such as the Bakhtegān Wildlife Refuge, Tūrān Protected Area, and Golestān National Park. The hunting of swans, pheasants, deer, and various other animals and birds is strictly prohibited.