ponderosa – from Latin pondus, meaning ‘weight’ and referring to the large size of this conifer

Native range: British Columbia to California

Leaves:

• needles in bundles
• 3 per bundle (~2)
• long (4–6 inches; 10–20 cm)
• dark green
• clustered at ends of branches

Cones:

• male cones yellow & strongly clustered
• female cone 5–8” long, near tips of branches
  • scales chocolate-brown, with a thickened, yellowish-brown, strongly prickly tip
  • reddish purple when young

Other characteristics:

• evergreen tree to 200 ft.
• bark of younger trees deeply furrowed, cinnamon colored
• bark of older trees like jigsaw puzzle pieces
• bark smells like vanilla or butterscotch

Relevant info:

• may live up to 600 years without fire, but in landscapes characterized by fire intervals of <20 years
• important timber tree
• most far-ranging Pinus in W. North America with many subspecies
• before fire-suppression practices, fire maintained Ponderosa pine as a dominant species throughout its range
• state tree of Montana

Ecology & Adaptations:

• native to east of the Cascades, British Columbia to Baja California, east to the Dakotas and Texas
• mostly inland but in a few localities in the Puget Trough, Washington, and the Willamette Valley Oregon
• found in mostly dry areas in open forests at low to moderate elevations
• pollinated by wind, though some self-pollination occurs
• seed dispersal by wind and animals
• winged seeds are buoyant and travel short distances
• birds and mammals disperse seeds, often farther than wind carried them
• seeds buried in caches by rodents (such as yellow-pine chipmunks and golden-mantled ground squirrels) or Clark’s nutcrackers have a better chance of establishing than seeds dispersed to the forest floor by wind
• seedling establishment:
  • viable seeds stratify naturally over winter and germinate the following spring
  • few seeds actually establish
  • for those that do, growth is most favorable on open sites with light shade
• no vegetative reproduction
• fire adapted:
  • thick, flakey bark
  • few low branches that can catch fire in low- or moderate-intensity fires
  • seedlings establish from seeds in remaining crown cones or blown in from off site or carried in by animals
  • initial allocation of growth to taproot, rather than stems and needles, aids post-fire regeneration because long taproots allow seedling to access soil moisture in lower soil profiles even on blackened and hot, burned-over soils
• herbivore/microbial defense – compounds (including phenolics, flavonoids, terpenes and tannins) deter herbivory and protect against microbial infection
• insect defense:
  • this species is susceptible to bark beetle attacks, especially in association with fire damage or drought stress
  • fire induces resin duct formation, and high resin flows and formation of new ducts increase resistance to beetle attacks
• low nutrient conditions – association with mycorrhizae facilitates water and nutrient uptake
• shade intolerant
• succession – successionally stable or climax species on low-elevation, dry sites and seral (later phase) on more mesic and mid-elevation sites