This document discusses the Ponderosa pine tree, describing its key identifying features like jigsaw bark and bundles of three needles, as well as its ecology. The Ponderosa pine is the dominant pine species in the high desert regions of western states, where it forms dry, spacious groves. Its extensive root systems and reliance on wildlife for seed dispersal help the trees survive, though threats include logging, beetles, browsing animals and cattle.

1. Ponderosa Pine
• Jigsaw bark
• Three needles/bundle
• Large pines of basin
• Important wildlife trees
• Dominant pine of high desert
• Logging in basin/west
• Yellow Pine

2. Ponderosa Pine
Pinus ponderosa

3. Ecology
• Every western state
• Young trees have dark blackish bark
• Older trees orange yellow bark
• Arid transition zones
• Dry spacious groves
• Extensive horizontal root systems determine
spacing of large trees

4. Ecology continued
• Man and beetle main mortality factors
• 250-500 years
• Studies show that in some areas, 85% of
trees come from abandoned chipmunk
caches
• Bitterbrush and sagebrush important to
survival of young trees(shading)

5. Ecology continued
• Seeds eaten by squirrels, chipmunks, grouse,
nutcrackers, ravens, quail
• Browsing mule deer thin seedlings
• Reproductive maturity reached at 50 years
• Scientific studies show that browsing by cattle is
perhaps the most objectionable deterrent to
satisfactory reproduction of this valuable tree