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cambium can remain undamaged. Ponderosa pine roots run deep thus providing further protection. Hot slow moving fires will often destroy the duff layer and cause root damage to shallow rooted species such as Colorado blue spruce. Vegetative Recovery after Wildfire .,."..... .;' The use of an axe can reveal the cambium layer sufficiently to evaluate fire damage. Trees beyond the pole stage (about the size good for fence and corral posts) are very resistant to fire damage if they are not too crowded. The crowns of larger trees are more elevated, thus protecting the buds and foliage from heat scorch. Cambium damage can be evaluated by chipping away a small section of bark with an axe. A healthy cambium is a light tan or cream color. Dead cambium is dry, brown or gray, and has a sour fermented smell. A large amount of pitch exuding from deeply charred bark can also indicate cambium damage. Crown scorch and bud kill is considered the principle cause of death. In healthy, well- spaced stands mortality is usually low. Ponderosa's lengthy needles can provide sufficient protection to the buds, which are large and well protected by heavy scales. Douglas-fir shares similar bark characteristics with ponderosa pine. Both are more fire resistant than spruce and true fir, Douglas-fir needles are very short in comparison with ponderosa pine. These offer little protection to the small buds. Douglas-fir saplings are more prone to loss than pon'derosa pine. . Trunks 9 inches in diameter or larger can survive low to moderate intensity fires. If 25 percent of the cambium is damaged, a Douglas-fir will most likely die. In addition, Douglas~fir has shallow lateral roots that are susceptible to damage. Currently, many ponderosa pineIDouglas-fir forests are over.crowded. This leads to higher mortality rates due to fire than in well-spaced stands. Regeneration From Seed Natural reestablishment of ponderosa pine and Douglas-fir can occur from seed depending on the presence of cones on the tree. Most pines do not develop cones every year. Cones of pine require two seasons to mature. Cones typically mature and release their seeds to the wind in late summer and early fall. In some cases cones may continue to mature on a top-killed tree and release a viable seed crop. While most pines have variability in cone crop production, the Douglas-fir is more regular. http://www.ext.colostate.edu/PUBS/NATRESI06307.html Cones of Ponderosa pine. Page 4 of 9 e. e e , 8/13/02