Today's entry was supposed to be posted yesterday, but we're still trying to determine the optimal settings for the new server, so it ended up crashing again last night. It shouldn't be too much longer before things are back to being stable, though.
I briefly spoke to the Vancouver Rhododendron Society last night about some of my trips to the Siskiyous, so while working through the images for that presentation, I pulled this one for BPotD today.
My inclination is to call this Jeffrey pine, but other common names are also in use, including bull pine and sapwood pine. This is primarily a California species, but it can also be found in the Siskiyous area of southwest Oregon and northern Baja California. As noted in the link, "Jeffrey pine often dominates and is almost entirely restricted to soils derived from ultramafic rocks- peridotites and their alteration products, serpentinites", and this is indeed the case in the Siskiyous, where the presence of Jeffrey pine indicates serpentine soils. In non-serpentine soils nearby, the similar Pinus ponderosa grows instead.
Commercially, the two species of pine are treated as indistinct, but there are biological differences. Some of these are summarized in the Wikipedia article on Pinus jeffreyi, such as Pinus jeffreyi having overall larger cones with inward-pointing barbs and needles that are glaucous (having a whitish to bluish waxy or powdery coating, such that the colour appears muted). Naturally-occurring hybrids between the two species are rare, in part because of the different times of pollen production and reception: in areas where the two species overlap, Pinus ponderosa releases/receives pollen 4-6 (-8?) weeks prior to Pinus jeffreyi. Wood chemistry is also different with respect to presence / absence of certain monoterpenes; n-heptane, n-nonane, and n-undecane are present in Pinus jeffreyi and seemingly absent in ponderosa pine (see: Anderson, AB, et al.. 1969. Monoterpenes, fatty and resin acids of Pinus ponderosa and Pinus jeffreyi. Phytochemistry. 8(5): 873-875.).
Conifers.org, as always, has excellent additional reading about conifer species: Pinus jeffreyi, and Calphotos has additional images: Pinus jeffreyi.
A note for local readers: I'll be speaking on Plants of Southern Interior British Columbia on Monday @ noon -- one of my favourite visual presentations.
Botany / gardening resource link: Florida's Native Wildflowers from the Florida Wildflower Foundation was recently launched, containing a weblog, a bloom map, a section on growing Florida wildflowers and much more. Definitely worth a peek and the bloom map is something to keep in mind if you plan to travel around the state.