Flora and fauna of the Athens County area, and occasionally habitats outside Ohio. Subject matter will consist of both interpretive material and taxonomic issues in plant and animal identification.

Monday, August 4, 2014

Carex Sedges part 2-star, spiny & bushy species



I think of star shapes or pinwheels when I see the next two species. Fruits spread outward like a rosette. Perigynia on these are much smaller than anything posted in part 1.

Curly Rose Sedge, Carex rosea.


 

Star Sedge, Carex radiata. Although they can be found in wetter areas, these two are woodland species. Often when you consider habitat, you can eliminate that long list of endless or look alike species. Fruits are spread out along the stem and radiate outward in a star pattern. The styles of rosea are pinkish-red and recurved (see arrow above). They tend to be straight on radiata. The perigynia of both have ridges along the edge, giving them a flattened look.

I'm treating them together because the visible differences are minute, and these were once combined as the same species. radiata is occasional in S.E. Ohio, more common up north, more often seen in wet woods, and has leaves 2mm wide. rosea is found statewide, in drier sites, and the leaves are 3mm wide. The swollen portion of the perigynium is 4mm in radiata, only 2mm in rosea. Have fun with that.


I call this next group the Spiny Sedges. That is because they remind me of this old Florida nemesis. This is Sandspur (Cenchrus). If you go barefoot in the south, you'll soon be familiar with this. While these sedges don't get stuck in your skin, they have 'the look'. This group has only TWO stigmas rather than the more common three on their achenes.


Bur-reed Sedge, Carex sparganioides. Common in woodland situations, less so in wetlands. The way to separate it from the other spiky ones is to start at the top of the stem. The fruit are clustered together, but as you go down they become farther apart, sometimes with wide spaces between them. The round shape and distance between them are the source of the common and latin names. Individual perigynia are boat shaped. Concave in the middle, with curled up edges.


Clustered Sedge, Carex aggregata. The name suggests the spikes are all aggregated or crowded at the upper end. That's fine in separating from the above species, but there are still others who crowd their fruit like this. Rather than boat shaped, the perigynia are more flattened. With a hand lens you'll see both these species have wide shaped perigynia with short blunt beaks.


Prickly Sedge, Carex stipata.

Smooth-sheath Sedge, Carex laevivaginata. Once again I am guilty of treating two species together because of their similarities. Unlike the last two species, these have longer pointed beaks on the perigynia. It is stated that stipata has a longer fruit cluster than laevivaginata, and the individual perigynia are pale colored at their base (see arrows above).

The real difference between these two is in the stem sheath, which I'm afraid I didn't photograph. Prickly Sedge has leaf sheaths that are cross-puckered, which means it has horizontal wrinkles. Smooth-sheath Sedge does not, hence the common name.

To review these last several species, sparganioides, aggregata, and in this case C. normalis on the right, all have a wider perigynia ending in an abrupt tip (see blue arrow). stipata and laevivaginata, the two on the left, have long tapering beaks, giving them a sharper appearance (orange arrow).



Yellowfruit Sedge, Carex annectens.



Brown Fox Sedge, Carex vulpinoidea. I also want to discuss both of these together. Each of these have large clusters of fruit and long horizontal bracts (black arrow). Their perigynia are round on the bottom, flat on top. The beak is short when compared to the length of the perigynia. vulpinoidea beaks are the longer of the two. Speaking of long, Fox Sedge has a greater amount of fruit spread along the main stem, more so than ANY other species. On annectens the spikelets are more tightly compact, stacked in an alternate pattern around the stem.

C. annectens






C. vulpinoidea


In this second set of pics, look for other differences. The fruit of annectens turns yellow with age, while vulpinoidea turns brown. The leaves grow well past the fruiting stalk on vulpinoidea, they are shorter than the fruit on annectens. vulpinoidea is much more common and found state wide.


Continuing with my unorthodox classifications, I call these the bushy or broom-like sedges. (Wickipedia photo)


Carex cephalophora. Short-headed Sedge, but there are lots of other common names. Compared to the others in this group, it has the shortest and smallest amount of spikelets clustered into a little head. While these photos show very few, there can be more, but still less than the other species. These remind me of the wildflower fruits known as Avens.


Crested Sedge, Carex cristatella. Clusters of round stemless spikelets are crowded together at the top, with 1 or 2 loosely below. Each perigynia radiates outward, giving it a bushy appearance. The tops are spiky, and resemble a bird crest.


Broom Sedge, Carex tribuloides. This prickly or bushy looking species does NOT have all its fruit clustered at the ends, but spread out and with alternating spikelets along the stem. Each perigynia is flattened and ends in a pointy beak. I welcome more information on these. I think my descriptions are a bit vague, and without enough detail. Members of the Ovales group are difficult to do by photos. Most characters are hand lens minute.


Straw Sedge, Carex normalis. A woodland rather than wetland species. Spikes are all gathered around the end of the stem, but loosely arranged. The perigynia border on looking more spiny than bushy.


Prickly Quill Sedge, Carex echinodes.

Greenish-white Sedge, Carex albolutescens. It's one thing to put up pictures with names, it's another not to say much about them. I'm simply not familiar enough with these. Like cephalophora, both these species have fewer and smaller spikelets than the previous species. They are loosely spread along the stem, and not restricted to the top. This group of Carex have bent styles at their base (see arrows), but how many species does that apply to?

Prickly Quill Sedge is a new species that was lifted from Carex tenera. Greenish-white Sedge is found way up in the N.E. part of the state, and a few counties in southern Ohio. It's considered rare, but probably due to misidentifications.

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