Wednesday, April 16, 2014

Identifying Mount Rainier's Violets



Day 196: I thought I'd share with you a little piece of interpretive material I put together yesterday. Enjoy!

"Oh, I know that one. It's a violet." Ah, but Mount Rainier National Park hosts quite a number of different species of Violas and they can be very difficult to tell apart unless you know what identifying features separate them.

First of all is COLOR. Contrary to the name, many of our violets are actually yellow, but we have pale purple ones as well. The next identifying feature to check is leaf shape. Does it look like a heart? Is it round or pointed? The leaf margin (edge) will tell you a lot. Is it smooth or serrated? Or is it deeply incised and composed of separate leaflets? Once you've determined these things, narrowing down an identification gets a little stickier.

For the sake of this discussion, I plucked a specimen of Viola glabella (Stream Violet) from my own yard so that we could examine some of the finer points of separation. All of these observations can be made without picking a flower (which, of course, is not allowed in the Park!). It is helpful to carry a small magnifier with you for closer examination.

Some of our Violas have fine, dark lines on one or more of their petals. Some have petals which are pointed rather than rounded. Some have tiny little furry "beards" similar to those found on iris falls (you'll have to put that magnifier to work to observe them). Some have a structure called a "spur" on the reverse side of the lower petal. This spur may take the form of a pouch-like sac or a slender "tail" like you would see on a domestic Nasturtium, but much smaller. All of these points help us determine the true identity of those little yellow faces smiling up at us from the streambanks and beside the trails.

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