are commonly on the edges or in gaps.
The original Jepson manual had Jeffrey Pine as a variety of Ponderosa and it is often very hard to tell the two apart in the field. The keys separate the two by cone size and shape. Where they overlap (5000-6000 feet) the cones look the same, and they do hybridize with each other, in certain areas. At about 6000 ft. non-stressed Jeffrey Pines start showing up amongst the stressed Ponderosa Pines.
Soil and climate notes
The soils are commonly slightly acidic and can range from a red clay, to granite to sand on hard pan. In southern California many of the valleys that had a pine forest had soils of sand on hard pan. Pines can grow in alkaline soils, and even poor -draining soils, but they usually do not live long, except in their range. The common life span for pines is only about 7 years in places like Bakersfield, Barstow, or Shandon. At 5000-6000 ft. Jeffrey Pine and Ponderosa Pine can tolerate a pH up to 7.8.
The pines in the Yellow Pine Forest plant community need about 20-25 inches of winter/early spring rainfall/snow melt to regenerate and stay healthy. In lower rainfall areas, such as southern California, the pines can compensate somewhat in older stands with fog drip, but if a large -area fire, weed invasion or clear-cut occurs, the trees cannot regenerate on their own, because there is just not enough rainfall. So, if your project is on a ridge line or valley facing the wind where there are commonly fogs or passing low clouds , and if you water the 'forest' for the first few years (not with drip), the pines will be happy, and the associated plants will live.
Plant communities are flavors, not lines in the sand. Many people have described California's plant communities in many different ways. A good analogy is the different names given to Rocky Road Ice Cream, and the different formulations of flavors and ingredients that the name has been applied to. If you're trying to repair, landscape in, or duplicate the Yellow Pine Forest plant community, remember to try to match the best you can, then don't worry about it. It will never be perfect, because there are no perfect flavors and ingredients, but hopefully everyone will recognize the 'flavor' and fragrance as Yellow Pine Forest.
Suggested Plant Lists:
The plants listed below and on the following pages are suggested for a garden that is mulched with shredded or chipped cedar, redwood or pine needles and in sandy loam ( i.e. one gal. water will drain out of an 8"x8"x8" hole in 15-30 min.) and watered only for 10 min. once every two week in spring summe
r and fall only.
The following list is also found at http://www.laspilitas.com/ where you may click on any plant to learn more about it.