Great Basin Bristlecone Pine

Description

Great Basin bristlecone pines can have one or many trunks. At low elevations, the trees grow straight, but at high elevations, the trunks become twisted. The root system is very shallow to allow maximum water uptake in arid environments. The female pine cones are dark purple in color and have bristle-like prickles on the scales, hence the tree’s name. At low elevations, bristlecone pines grow to 60 feet (18 meters) tall and five feet (1.5 meters) in diameter. Bristlecone pines at higher elevations may be half this height.

Range

These pines are found in California, Nevada, and Utah across a range of altitudes. At higher elevations, they can be found in pure stands. Great Basin bristlecone pines are well-adapted to high-elevation habitats in areas with rocky soil, low rainfall, long winters, and are drought resistant. At high elevations, there are fewer insect pests and disease-causing fungi, which may help the tree maintain a longer lifespan.

Life History

The Great Basin bristlecone pine is a conifer, which means it produces seeds in cones rather than in flowers. Pines are monoecious, meaning each tree has both male and female pine cones. The male cones produce pollen and the female cones produce ovules which, when fertilized with pollen, become seeds. Pollination occurs by wind. Bristlecone pines can produce seeds for thousands of years, but they produce fewer as they age.

The bristlecone pine is the longest-lived species in the world. A few are known to have lived for over 5,000 years. However, growth is extremely slow. A 40-year-old bristlecone pine may not even reach six inches (15 centimeters). In harsh conditions, bristlecone pines stop growing in height, but their trunk diameter continues to increase throughout their lives.

Conservation

Because of its small, fragmented distribution, this species is considered to be vulnerable, although it does occur in protected areas. It is susceptible to disease and severe fires. Scientists are uncertain about what effects climate change may have on bristlecone pine.

Fun Fact

This species is highly tolerant of drought. One tree was found with 35-year-old pine needles (modified leaves) that were still functional and photosynthesizing, despite periods of drought.

Sources

NatureServe Explorer

The Ancient Bristlecone Pine

The IUCN Red List of Threatened Species

U.S. Forest Service