Saturday, April 25, 2009

A Floral Dilemna:

For my systematic botany class, I've been collecting and pressing plants for a herbarium. Of course, they also have to be correctly identified via keying them out with a dichotomous key. Many of the specimens are easy to nail down right away...and the flora is used primarily to confirm the identity of the plant. For others, it can be exceptionally difficult unless you have as much information about the plant as possible, such as roots, seeds, flowers, leaves, habitat and visual access (dissecting scope) to minute structures such as the filaments of the stamens, or the placentation of ovaries that you can hardly see to begin with (let alone how the ovules within them are attached). You don't really notice it much until you try to do this, but it isn't terribly common to be able to see flowers and seeds development on a single species in a single day, especially wildflowers. Their whole program is one of blooming, setting and ripening the seed all as quickly as it can for optimum survival of the next generation of plants. That's the introduction to my problem. Here's the problem:

This plant is Lomatium gormanii


© Gerald D. Carr

And here is a picture of another plant, also in the apiaceae family, Orogenia linearifolia:





They look a lot alike, don't they? I have a plant that I'm pretty certain is Lomatium gormanii, but someone who knows more about plants than I do says it's Orogenia. He only glanced at my specimen, and it was pressed and dried, and he didn't see where it was growing, *and* these two are almost identical to the casual observer as far as I can tell, so I don't know how he can say that, unless he is seeing soemthing that I have overlooked in the flora and plant guides I've consulted, such as a dramatic size difference between the two. The roots are almost the same, the flowers are the same color, leaves very similar, even the minute detail of the flowers are very much alike.

Part of why I think it's Lomatium gormanii is that the Orogenia grows in damp soil, whereas L.gormanii grows on dry rocky slopes and rocks, which is exactly where I found it. That site will be dry as a bone within a month or so. Also, Orogenia apparently was collected for food and makes sizable roots, but this plant has only a small sub-globose tuber, about the size of a little pearl onion. And Orogenia linearifolia typically grows in large groups which flower all at once, and the umbels are only 1/4" across, whereas this plant has umbels which are slightly larger and there were only a few plants on the site, hardly the blanket of blooms described of the other species.

Lastly, I should mention that neither of the plants are present in most field guides for the area, either online or in text. Orogenia linearifolia is apparently a species of concern in Montana, and sightings of the Lomatium gormanii aren't terribly common either in this area, from the information I've found so far. So either way, It would seem I've found an interesting plant. I just wish I knew what it was. Of course, it doesn't help matters at all that the lomatiums exhibit quite a bit of morphological variation.

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