Rocky Mountain Floristic Region facts for kids

The Rocky Mountain Floristic Region is a special area in western North America (which includes parts of Canada and the United States). It's like a huge natural zone defined by scientists Armen Takhtajan and Robert F. Thorne because of the unique plants that grow there. This region stretches a long way, from Kodiak Island in Alaska all the way down to the San Francisco Bay Area and the Sierra Nevada mountains in California.

This big plant region has two main parts: the Vancouverian Province, which covers the coastal areas and mountains near the Pacific Ocean, and the Rocky Mountain Province, which includes the famous Rocky Mountains and other mountain ranges. While no entire plant families are found only here, many specific types of plants (genera and species) are unique to this region.

Where is the Rocky Mountain Floristic Region?

This amazing plant region goes from Kodiak Island in Alaska down to the San Francisco Bay Area and the Sierra Nevada mountains in California. It runs along the Pacific Ocean on its western side and borders the Great Plains on its eastern side. This means it includes the Rocky Mountains and the Pacific Coast Ranges.

It touches other plant regions too! To the north, it meets the Canadian Province. To the east, it borders the North American Prairies. To the south, it connects with the Californian Province. Sometimes, the exact lines where these regions meet can be a bit blurry.

What Kinds of Plants Live Here?

Even though no whole plant families are found only in the Rocky Mountain Region, it's home to many unique plant groups and species. For example, specific types of plants like Sidalcea, Luetkea, Whipplea, Vancouveria, Lithophragma, Tellima, Tolmiea, and Luina are found only here.

Many different kinds of Arnica, Castilleja, Erigeron, and Lomatium plants also thrive here. This region is especially famous for having the most types of conifer trees (like pines and firs) in all of the Americas!

Most of the wild areas in this region are covered by temperate coniferous forests. These forests are full of trees like Pinus ponderosa (Ponderosa Pine), Pinus contorta (Lodgepole Pine), and Pseudotsuga menziesii (Douglas Fir). Higher up in the mountains, above the tree line, you'll find alpine tundra, which is a cold, treeless area with small, tough plants.

The Vancouverian Province

This part of the region covers the coastal areas, including the Pacific Coast Ranges. Some very special plants are found only here, like the giant Sequoia sempervirens (Coast Redwood), Sequoiadendron giganteum (Giant Sequoia), and the unique pitcher plant Darlingtonia californica. Other plants like Vancouveria and Whipplea are also unique to this coastal area.

The Rocky Mountain Province

This part of the region includes the Rocky Mountains and other nearby ranges. Long ago, during the Ice Age (Pleistocene), this area had a lot of glaciation (covered by glaciers). Because of this, fewer plant species are found only here compared to the Vancouverian Province. Many of the plants in this area are also found in the Canadian Province and other northern regions.