Pinus ponderosa are a species of evergreen conifer trees found most commonly west of the Rocky Mountains. They have a red-yellow bark, with significant diameter records along with dynamic height and age recordings. They are the most commercially important western pine, as well as the most common pine in North America. They are completely monoecious and are not consistent in their flowering periods. They are found from Canada to Mexico, and from the Pacific Ocean to the Rocky Mountains. They can live to be as old as 600 years old, and can grow up to heights of 232 Ft.! Pinus Ponderosa are perennial.
Pinus ponderosa are straight trees, with deep roots and thick bark, as well as high limbs with a flat crown. Their diameter is commonly between 25-60 inches with heights commonly between 75-150 ft. There have been recordings of Pinus ponderosa with diameters of 1031/2 inches, heights of 232 feet, and ages between 300-600 years. They have cones which are oval-shaped, 1-7 in. long, that usually mature in the summer and sessile.  
All ponderosa pines are monoecious, meaning they are unisexual, and can sort of "asexually" reproduce. What happens is they are self-pollinated, meaning that they pollinate their own flowers, and produce flowers with the male (strobili) and female (conelets) reproductive systems both in the flower. Then, the following year, the cones are fully ripe and the seeds are ripe. From the time the seeds ripen, they are usually shed for a period of months. In most cases, flowering happens after winter. Pinus ponderosa aren't consistent in any way when it comes to seed production. In some areas, production happens every 8 years, in some areas just 2 years.
Ponderosa Pines are prevalent from Southwestern Mexico to Canada, and from Nebraska to the Pacific Ocean. They need annual precipitation, ranging from around 10 in. to 30 in.. As for extreme climactic support, there are places like northern Arizona where they grow and the annual precipitation is around 6 in., and then there are places like Sierra Nevada, California where the annual precipitation is around 70 inches. Ponderosa Pines can grow in almost every kind of soil, ranging from igneous soils to sandstone. They are found anywhere from below Sea Level to 10,000 ft. Ponderosa Pines can survive in climates ranging anywhere between -40°F- 110°F.
Ponderosa Pines are the farthest right on the conservation status scale, meaning they are of the least concern when it comes to extinction. Still, with them at least showing up on the scale, it warrants concern, not warning, but concern to use intelligence when thinning out areas containing Ponderosa Pines. They aren't in very big danger when it comes to fires, though, because they mainly have higher limbs, deep roots, and thicker bark. What's perplexing is that they are the most common tree in North America, but they are listed as in the Least Concern on the Conservation Status bar. The Pinus ponderosa seedlings die off very easily, and with them being extremely prevalent in the northwest of the United States, creatures such as squirrels and birds carry off their seeds and eat them or destroy them, so the problem isn't entirely human-related. Wildfires can easily kill of seedlings, but as soon as the Ponderosa grows into maturity, it's bark is thick with higher limbs, so it's harder to burn them away, especially with their deep roots. 
- Ponderosa Pine Conifers
- Ponderosa Pine Wikipedia
- Ponderosa Pine Northeastern Area, State and Private Forestry, USDA Forest Service
- Ponderosa Pine Virginia Technological Institute