Typically forms dense forests of slender trees up to 40m tall, often in nearly pure stands of Pinus contorta ssp. murrayana. More open stands up to 20m tall occur on dry sites or near timberline. May form krummholz at timberline. The trees in the moister, denser stands are relatively short-lived, and if the stand has not burned for a long time, fallen trees, branches and needles cover the ground. The understory is normally sparse in these dense stands, but low shrubs and perennial herbs occur abundantly in forest openings. There is much less litter in the drier, more open stands; other tree species occur occasionally and understory plants are scattered throughout the stand. Flowering of most plants is concentrated in the early summer; growth of at least the smaller plants may be limited by drought in late summer. Most plants are dormant from fall through spring.
SITE FACTORS:
Typically occurs at elevations with long, snowy winters and cool, dry summers; colder in winter and usually drier than Red Fir Forest (85310). Often best developed in the transitional elevations between the Upper Montane Coniferous Forest (85000) and the true Subalpine Coniferous Forest (86000). At its lower limit it occupies cold, moist sites within the Upper Montane Coniferous Forest; at its upper limit it occupies dry, exposed sites at timberline, especially in the southern Sierra Nevada and in southern California. Apparently tolerates large variations in soil and moisture factors, but most commonly occurs on rocky, well-drained soils. Where it forms dense forests, it is subject to devastation by fire or epidemic outbreaks of the Lodgepole Pine Needle Miner (Coleothechnites milleri). Reseeding is relatively rapid following fires, and Lodgepole Pine Forest is often successional in areas that are eventually dominated by other species. However, this fire succession is more universal in the moister forests of the Cascades and northern Rockies.
DISTRIBUTION:
Scattered and poorly developed in the Klamath Mtns. More extensive stands occur east of Mt. Shasta on the Modoc Plateau of eastern Siskiyou and Shasta Counties. Scattered in the higher parts of the Warmer Mtns. in eastern Modoc Co. Abundant in the vicinity of Mt. Lassen. Scattered in the northernmost part of the Sierra Nevada, then very abundant from Sierra Co. to southern Tulare Co. A few small stands occur in the White Mtns., Mono Co. Scattered in the highest portions of the San Gabriel Mtns., Los Angeles-San Bernardino Counties; abundant on the upper slopes of the San Bernardino Mtns., San Bernardino Co.; locally abundant near the summit of Mt. San Jacinto, Riverside Co.; the southern limit is on the summit plateau of the Sierra San Pedro Martir, Baja California. Extensively developed on the east side of the Cascade Range in Oregon and in the northern Rockies. Elevation 6,000-8,000 feet (1800-2420m) in the north, 9,000-11,000 feet (2700-3330m) in the south. Common as much as 2,000 feet (610m) lower in cold, moist sites such as stream valleys and meadow margins.
UPDATE: 11/97
Source: Holland, 1986
Digital Text: NatureBase