Сосна клауса: Экология и разновидности флоридской песчаной сосны.

Species of conifer

Pinus clausa is a species of pine endemic to the Southeastern United States. Its common names include sand pine, Florida spruce pine,

The tree is found in two separate locations, one across central peninsular Florida, and the other along the western Florida panhandle coast into the Alabama coast. There is a range gap of about between the populations (from the Ochlockonee River to Cedar Key). The sand pines of the Florida peninsula and of the Florida panhandle coast differ enough to be classified into two varieties or races, Pinus clausa var. clausa ("Ocala"), on the peninsula, and P. clausa var. immuginata ("Choctawhatchee"), along the panhandle coast. While most peninsular sand pines (var. clausa) have non serotinous, or open, cones, most of the panhandle sand pines (var. immuginata) have serotinous, or closed, cones. Sand pine is largely confined to the very infertile, excessively well drained, sandy habitat of Florida scrub. It is often the only canopy tree in the Florida scrub ecosystem. Stands of sand pines in peninsular Florida tend to be dense and of the same age, while stands of sand pines along the panhandle coast tend to be more open than on the peninsula, and with trees of varying age.

Pinus clausa is a small, often shrubby tree from , exceptionally to tall. The leaves are needle like, in pairs, long, and its cones are long. Over much of its range, it is fire adapted to stand replacing wildfires, with the cones remaining closed for many years (clausa = closed), until a natural forest fire kills the mature trees and opens the cones. These then reseed the burnt ground. Some populations differ in having cones that open at maturity, with seed dispersal not relying on fires.

Pinus clausa woodlands are an important part of the Florida scrub ecosystem, and provide habitat for the endangered Florida sand skink, among other species. It is one of the few canopy trees able to grow in arid, sandy, and hot locations with minimal care. While the dense branching makes this tree unsuitable for wood production, it is often used for wood pulp.