Sedge Buster Lesson 9 - Section Porocystis - Yikes!
All righty then. We have 13 sheets of the Poroacystis caric sedges that have their spikes, terminal on the culms. These are named by the mighty wise as C. bushii, C. caroliniana, and C. complanata. Every sheet has been variously annotated over the years to two or another of these 3 specifics. With the help of my esteemed colleagues, Ray and the LDR, we are doing them again, as a team. The charactersitics of the section as a whole are trigonous achenes with three stigmas and predominantly gynecandrous (girls on top) spikelets, especially the terminal, most distal spikelet. Two of these with the above characters that are found in htese parts (Section Hymenochlaenae), which we won't be undressing tonight, have spikelets on flexuous pedicels, thus the spikes hang down, more or less. These are C. davisii and C. oxylepis.
In the picture around here somewhere we have two peryginia and two nearly naked achenes. Measuring the achenes and the peryginia may be the best way to identify these species. Here, the peryginias are a little more than 3mm and the achenes are a shade less than 2.5mm which fits most of the key descriptions of C. bushii best. Danger Will Robinson. Extant line drawings of these species are misleading. Also, you will have lotsa fun if you employ a variety of keys on these three species. Note the trigonous, that is, three-sided yellow achenes. Also, note the interesting, still attached, bent base of the style on the top of the achene.
This second picture shows a terminal spike with most of the peryginias fallen off and two lateral, more proximal shorter spikes with most of the peryginias still attached. In this case, you should be able to see that the male flowers are below the female on the terminal spikelet. The two lateral spikelets are probably entirely female. So here we have an example of a gynecandrous sedge with trigonous achenes. This specimen is from Bastrop County, '95.
The Porocystis are easy to recognize, but not easy to identify to species. Also, they do not appear to be much separated in their ecologies, if ye get my drift.
In the picture around here somewhere we have two peryginia and two nearly naked achenes. Measuring the achenes and the peryginia may be the best way to identify these species. Here, the peryginias are a little more than 3mm and the achenes are a shade less than 2.5mm which fits most of the key descriptions of C. bushii best. Danger Will Robinson. Extant line drawings of these species are misleading. Also, you will have lotsa fun if you employ a variety of keys on these three species. Note the trigonous, that is, three-sided yellow achenes. Also, note the interesting, still attached, bent base of the style on the top of the achene.
This second picture shows a terminal spike with most of the peryginias fallen off and two lateral, more proximal shorter spikes with most of the peryginias still attached. In this case, you should be able to see that the male flowers are below the female on the terminal spikelet. The two lateral spikelets are probably entirely female. So here we have an example of a gynecandrous sedge with trigonous achenes. This specimen is from Bastrop County, '95. The Porocystis are easy to recognize, but not easy to identify to species. Also, they do not appear to be much separated in their ecologies, if ye get my drift.
posted by ray pistrum at Friday, February 24, 2006
1 Comments:
This last picture was intructive of the methodology of fornewcations of the particluar example. It might be helpful for carexs to exhibit that size picture soes when the equipment ain't handy we got more than our poor imagination to rely on for the actual arraingement of them sex parts.
My ruminations had passed by midafternoon and I strolled about this place, my neighbor had conviently mowed some of the fields
( but on my recomnedation not so low as to hurt the clumps of little blustem) here about which makes it favorable for espyin little things tucked down close to the ground and with the more than inch of rain fall should get all the various contributions to the spring flora jumpin up.
I know a fella whose famliy has more than 200 arces5 miles north of lockahrt. It's up on a high plateau and lookin towards the west you can see San Marcos but it has a big drainage and a drop of 60-80 feet from the side on 183 towards the west. On the top where it's blackland clay there are many low spots with seasonal hydric species and there got to many more in the drainages plus they got stock tanks down there. It might be a nice place to look around.
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