The purpose of a meditation is not to be profound. Rather, you take a simple image or thought or process and stay with it for awhile. The results can be profound in ways unimaginable, though.
So this is a short meditation on something we all know.
Differences are discovered because similarities are known.
No difference in two leaves would be significant if we didn’t first begin with a profound similarity between the two. Only when we first have established what the two leaves share in common with one another (ex: photosynthetic capabilities, entire margin, lobed) are we able to conceptualize the differences (ex: length of petiole, pubescence).
No difference in two leaves would be significant if we didn’t first begin with a profound similarity between the two. Only when we first have established what the two leaves share in common with one another (ex: photosynthetic capabilities, entire margin, lobed) are we able to conceptualize the differences (ex: length of petiole, pubescence).
Or, we might take the two riparian grasses we have down at The Creek and which have been featured in earlier blog entries. Rabbit Foot Grass (Polypogon monspeliensis) and Canary Grass (Phalaris-caroiniana) are interesting to view with respect to their differences only because they are so similar that even the nature-lover slowly making his way down a streamside would probably mistake the two for the same.
Dyspepsia (from the Greek δυσ- dys- and πέψις -pepsis "digestion") refers to an upset stomach. In the previous entry we confessed having suffered several hours of dyspepsia following the consumption of minuscule amounts of a red berry (Solanum triquetrum) we had confused with another red berry (Capsicum annuum, var. glabriusculum).
Dyspepsia (from the Greek δυσ- dys- and πέψις -pepsis "digestion") refers to an upset stomach. In the previous entry we confessed having suffered several hours of dyspepsia following the consumption of minuscule amounts of a red berry (Solanum triquetrum) we had confused with another red berry (Capsicum annuum, var. glabriusculum).
Familia: Solanaceae
Species: Solanum triquetrum
(the Texas nightshade)
vs.
Familia: Solanaceae
Species: Capsicum annuum
(the chiltepin hot pepper)Species: Solanum triquetrum
(the Texas nightshade)
vs.
Familia: Solanaceae
Species: Capsicum annuum
In most ways, these two plants appear identical. One of the key differences is that the former causes dyspepsia without any Scoville scale-tipping flavor.
Life itself might be defined according to the similarity(ies) present. An appreciation for taxonomy and what we find by navigation through keys for plant or animal depends upon at least some small ability to comprehend the similarities of any given family or class. But Life might also be defined according to what is termed biodiversity, an endlessly reiterated truth found mainly at the end of the keys where the trail ends at any given species. Thus, any meaningful definition of nature will somehow incorporate both the concept of unity and diversity.
Harlin spends time with the keys. Below are some excerpts from some of his recent letters to me:
You are probably convinced that I am not kidding when I say that I think the puzzles provided by the inconpicuous wayside weeds are very interesting. I mentioned before that people who identify plants for a living must have a completely different attitude than I do about finding a name. When they fail it may be serious, and from what I've seen . . . they make it a team effort and do a lot of legwork back to the samples they have stored in the herbarium. I don't think they get to quit and take it up later when they are back in the mood.
~
Harlin spends time with the keys. Below are some excerpts from some of his recent letters to me:
You are probably convinced that I am not kidding when I say that I think the puzzles provided by the inconpicuous wayside weeds are very interesting. I mentioned before that people who identify plants for a living must have a completely different attitude than I do about finding a name. When they fail it may be serious, and from what I've seen . . . they make it a team effort and do a lot of legwork back to the samples they have stored in the herbarium. I don't think they get to quit and take it up later when they are back in the mood.
On the other hand I use keys as guided tours which take me to places I've never been before. Having the internet makes the journeys even easier, since now I have scans of herbarium sheets, handy photographs, and even more words to read through. Many times there are details that reassure me I got the right answer. Now and then I don't get the extra details and sometimes--like this one--I am amazed the plant people say they are two different species.
Everything about distinguishing Lolium perenne from L. temulentum that I've found boils down to the length of the outward piece of chaff they call the second glume.
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| Darnel ryegrass -- Lolium temulentum |
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| Lolium temulentum |
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| Perennial ryegrass -- Lolium perenne |
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| Lolium perenne |
I would never have thought there were two kinds of grass just looking at them. Not until I saw the [first picture] did I even know there was a look-alike to L. perenne which I've been seeing all over the place for years. About a week ago I had just found the Lolium with the long glume. I went to include the [first] picture thinking it was the same grass and there was the Lolium with the short glume. Definitely the botanic version of the twilight zone.
So, if we take at least a hundred years years of botanists at their word, then I'm going to say you got both of 'em growing out at your creek. If you look at the photo of the floret from the [second photo above] you can see that second glume is way long and this one is definitely shorter.
But hey, that's the point. With the TV twilight zone, you are just watching someone else wander around lost. With nature you can experience the twilight zone for yourself up close.
HH
Keys are made by experts. When I think they are wrong, then most of the time I discover it is me and not the key. However, that leaves some times when I check and double check and I still would bet that I am right and the key is wrong. Of course, we are talking a bet in the range of about a dollar.
For two keys--the Gould book and the Shinners book--the genus Bromus is put into a category where the awn comes out of the end of the lemma, either from the tip or from between two teeth. In the Shinners book the grass I'm looking at doesn't fit into any of the alternate choices. In the photographs in this page, one can see that the awn is back from the tip.
The FNA says the awn "arises 1.5 mm or more below the lemma apice". Okay, the awn is not too far back, but 1.5 mm from the end could be thought of as coming out of the back in the opinion of any number of citizens who are a mind to look at such things. I don't mind so much, but I did want to explain how I can get the idea I'm right and the key is, well, not clear. I've included [below] my photos of glume tips and lemma tips. This brings me back to my basic theory of nature watching. I think there is a good chance I have a reasonable guess about this name. But, there is some grass with tips like this and I wouldn't have really explored how they look unless I was struggling with concepts like "how far back is back?"
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| Bromus Japonicus |
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| Bromus Japonicus |
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The next grass is easier--Limnodea arkansana (Ozark grass). In the key to all the genera of grasses in Texas, Gould's book does not have a pointer to Limnodea. He has an entry for it, and in fact it was the picture that made me start checking whether this was the grass I was working with. Sometimes I miss things, but as long as I don't find that genus listed in the key I will be thinking I am right and Frank Gould left something important out.
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| Ozark grass -- Limnodea arkansana |
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| Limnodea arkansana |
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| Limnodea arkansana |
Ozark grass is one inconspicuous little plant. I only saw it because I was trying to take a picture of something else and it was in the way.
HH
~
Carol saw three black-bellied whistling ducks yesterday in a tree up on the top part of Whitman's Rough. Very jealous.
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