General: Tree to 40-50 m tall; bark thick, deeply furrowed, dark reddish-brown or blackish when young, changing to cinnamon red when older and exfoliating as irregular scales.
Leaves: Needles mostly in threes, often twos, occasionally fours or fives, (10) 12-20 (25) cm long, clustered towards branch ends; yellowish-green.
Cones: Seed cones near branch tips, deep reddish-purple when young, maturing late in second year, turning brown; egg-shaped, 8-14 cm long; scales brown with thickened, yellowish, prickly tip; pollen cones yellow to purplish, strongly clustered.
2. Needles in bundles of 3, 12-20 cm long..........................Pinus ponderosa
2. Needles generally in bundles of 2, 2-6 cm long.
3. Cones spreading at right angles or reflexed, the scales armed with prickles...............................Pinus controta (2 varieties)
3. Cones directed towards the apex of the shoot, strongly incurved or divergent, the scales unarmed or armed with minute prickles..................Pinus banksiana
1. Needles usually 5 in a bundle.
4. Cones long-stalked, 15-25 cm long, 6-9 cm thick at maturity; cone scales thin and flexible; seeds prominently winged..........................Pinus monticola 4. Cones sessile or subsessile, 5-25 cm long, cone scales thick, woody, and sometimes remaining closed, seeds wingless or wings short and remaining attached to scale.
5. Cones 8-25 cm long, opening at maturity; scales light brown, thinned somewhat toward the tip...............................Pinus flexilis
5. Cones 5-8 cm long, remaining closed and tardily shedding the seeds at maturity; scales purplish, becoming thickened rather than thinnish toward the tip....................................Pinus albicaulis
Source: The Illustrated Flora of British Columbia
Ecology
Ecological Framework for Pinus ponderosa
The table below shows the species-specific information calculated from original data (BEC database) provided by the BC Ministry of Forests and Range. (Updated August, 2008)
A very shade-intolerant, montane, North American evergreen conifer distributed in the Pacific, Cordilleran, and Central regions (rare in the coastal region of British Columbia). Occurs in cool temperate and cool semiarid climates on very dry to moderately dry, nitrogen-medium soils; its occurrence decreases with increasing latitude, elevation, and precipitation. Grows in pure or mixed-species stands (usually with Douglas-fir) on calciumrich, water-shedding sites in the southern coast-interior ecotone. Most productive on fresh and nutrient-rich soils within cool temperate climates. Characteristic of dry continental forests.
