Friday, August 29, 2008

Pacific Northwest Conifers

Okay, well, this may be the last post on my sojourn to the Pacific Northwest. But I had to touch on the coniferous forests once more before returning to Manhattan.

To whit, a few pics of the trees so prevalent in Washington. Below is yet another shot of Mount Rainier, primarily composed of Tsuga heterophylla and Abies amabilis, trees I mentioned briefly on Tuesday.

Douglasfir (Pseudotsuga menziesii) needles:


Note the white stomatal stripe down the side of the needle. Stomatal stripes are essentially strips of pores that exchange oxygen and carbon dioxide through the leaf's waxy membrane. A stoma is an individual pore on a leaf -- all plants have them, though in most cases they are microscopic.

Below, T. heterophylla. The species name most likely refers to the two different leaf types on Tsuga. Like Tsuga canadensis, Western hemlock has a small leaf that sits along the top of the twig. This leaf appears to be upside-down and displays that stomatal stripe otherwise existing on the undersides of the lateral leaves.


Though you are looking at the underside of a branch in this photo, it is overexposed so you can't see the stomatal stripes on the lateral leaves; I'm simply adding this pic 'cause I think it's really, really beautiful. Personally, it captured my experience walking around these forests.


Another shot of Tsuga, this time with an addition that looks suspiciously like Spanish moss -- the iconographic epiphyte that is ubiquitous on the live oaks in the south.


Whatever it is that is growing on the hemlock is probably an epiphyte (epiphytes are like parasites, only they survive off another organism without compromising said organism's survival) or a bryophyte (tree lichens), but I can't definitively find out. Please note I have just bastardized definitions of both epi & bryophytes. Non-vascular plants are way outside my expertise!

Happy Labor Day weekend!

1 comment:

Scot Steenson said...

Great pictures Jennifer! You really capture the essence of nature...

You know, I've been hiking through Jefferey Pines here in N. Cal the last few years and just finally realized their bark smells like vanilla. Ahh, the secrets of nature a endless...