status: Critically endangered, IUCN
Description and biology
Cypresses are resinous (containing a substance used in varnishes and lacquers) evergreens that have fragrant, durable wood. The true cypresses, of the genus Cupressus, are found in southern Europe, the Far East, and western North America.
A true cypress, the Saharan cypress, is covered in reddish- brown bark containing many deep cracks. It can grow to a height of 66 feet (20 meters) and a diameter of 13 feet (4 meters). It has upward-curving branches with flattened branch-lets that grow in two opposite rows. Its dense foliage consists of small green leaves measuring 0.04 to 0.06 inch (0.1 to 0.15 centimeter) long. The tree's small cones are yellow or gray- brown.
Saharan cypresses can live for more than 1,000 years.
Habitat and current distribution
This cypress species is found in Algeria on the Tassili Plateau in the central Sahara Desert. In the late 1970s, botanists (people specializing in the study of plants) estimated that 150 adult cypresses existed in this area. In the early 2000s, botanists have estimated the population at 153 individual plants; there are only three populations of this species.
The Saharan cypress inhabits sandstone or gravel areas where the average annual rainfall is just 0.7 inch (1.8 centimeters). It grows in the bottom of usually dry streambeds or valleys where water sometimes collects. In this way, it takes advantage of any moisture that falls on the area.
History and conservation measures
Over thousands of years, humans have cut down innumerable cypresses for their long-lasting timber. The gates of St. Peter's in Rome, which stood for 1,100 years, were made of Italian cypresses (Cupressus sempervirens). Today, the cypress is a symbol of immortality for many people.
Saharan cypresses are critically endangered because they do not reproduce very quickly, and humans have cut them down before they have had the chance. Most of the surviving trees are just over 100 years old. Grazing animals have also destroyed many cypress seedlings before they have had a chance to root and grow.
At the end of the twentieth century, it appeared that if remaining habitats were protected, then the Saharan cypress might have a chance of survival. In the early 2000s, however, the International Union for the Conservation of Nature and Natural Resources (IUCN) upgraded the species from endangered to critically endangered because a low water table in the Sahara has further impeded reproduction of the Saharan cypress.
DID YOU KNOW?
Between 5,000 and 10,000 years ago, the Sahara Desert was fertile. In the 1930s, scientists exploring caves on the Tassili Plateau in the central Sahara (where remaining Saharan cypresses now stand) discovered pictographs (rock paintings) that depicted grasslands, forests, and rivers. Inhabiting these lush landscapes were crocodiles, elephants, giraffes, hippopotami, and rhinoceroses. In some caves, the scientists discovered 16 layers of drawings, indicating that humans—both hunters and herders—had inhabited the region for thousands of years.