Thursday, September 29, 2011

Sept. 28, 2011 Uncommon Plants in a Wet Prairie

Bear Lake Prairie
 On the south shore of Bear Lake at the Merry Lea Environmental Learning Center of Goshen College is a wet prairie with a distinct set of plants now in bloom.  [Click for directions to the Learning Center south of Wolf Lake, IN; park in the learning center lot and follow the trail map to Bear Lake Prairie.]

The wet prairie soil is a marl, i.e., a gray mixture of sand, clay and calcareous sediment.  Some of the plants in the wet prairie only grow in wet, alkaline soils; others grow in a variety of habitats.

Trail through Little Blue Stem Grass and many other plants
Little Blue Stem grass is reddish this time of year.  It dominates this wet prairie, but it also thrives in drier habitats..  Between the tufts of Little Blue Stem many other plants, including several uncommon ones, are now in bloom.
Nodding Ladies' Tresses, Spiranthes cernua
Nodding Ladies' Tresses are 12-15 inch spikes 15-40 white flowers stick up in the grass; their long, thin, basal leaves are camouflaged by the grass leaves.
Nodding Ladies' Tresses
Bear Lake Prairie is one of only three places within 50 miles of Goshen where I find Nodding Ladies Tresses, Spiranthes cernua, although the USDA Plants Data Base lists it as occurring in most Michiana counties and in all but a few states east of the Mississippi.  Although S. cernua is widespread, it is nonetheless an uncommon wildflower - most people have neither heard of nor seen it.

Pictured below are other plants that grow in this prairie but which I find in few other places.
Purple Rattlesnakeroot, Prenanthes racemosa

Closed Bottle Gentian, Gentiana andrewsii
Marsh Yellow Cress, Rorippa palustris
The Marsh Yellow Cress has a tiny, yellow, four-petaled flower that is easy to miss; I saw just two individuals.  This is the first time I have ever seen or heard of this plant; I used two wildflower guides to key it out.  [Post script: Please see comments at the bottom of this entry; this identification may not be accurate.]

Shrubby Cinquefoil surrounded by Little Blue Stem
Many Shrubby Cinquefoil, Potentilla fruticosa, plants populate this wet prairie, but they are overshadowed by the Little Blue Stem.   Shrubby Cinquefoil also grows in drier habitats.   Most of the following plants also grow in a variety of habitats.
Blazing Star species, Liatris species
Blazing Star flowers up close
This Blazing Star may be Northern Blazing Star, Liatris scariosa, but after consulting several guides I am still not sure.
Flat-Topped White Aster, Aster umbellatus
There are at least three species of goldenrod growing in the prairie.  
Goldenrod species, perhaps Slender-Leaved Goldenrod
I'm uncertain about the goldenrod above, which for now I'm calling it Slender-Leaved Goldenrod, Solidago tenuifolia (or Euthamia remota in some guides) because of the flat inflorescence and very narrow leaves.  There were few plants of this species in the prairie.

The most common goldenrod in the Bear Lake Prairie is Ohio Goldenrod, Solidago ohioensis.  Ohio Goldenrod is primarily a wetland plant.
Ohio Goldenrod, Solidago ohioensis
Ohio Goldenrod inflorescence
Showy Goldenrod, below, grows in a variety of habitats, not only in wetlands.  They were much less numerous than the Ohio Goldenrod in this prairie.
Showy Goldenrod, Solidago speciosa
Close up of Showy Goldenrod flower heads
Goldenrod pollen does not contribute significantly to allergies. Ragweed pollen is the culprit, but because goldenrod and ragweed flower at about the same time, goldenrod often gets the blame.  Ragweed is one of the many native plants growing in Bear Lake Prairie, but goldenrods are far more numerous.
Common Ragweed, Ambrosia artemisifolia
[As I noted at several places above, I had some problems identifying some of the plants.  Please feel free to comment if you can help improve any of the above identifications.]

5 comments:

  1. Hi John. Nice post. Have you seen the Pycnanthemum verticillatum in Bear Lake Prairie? I found it there in 2008 and made voucher collections in 2009, and it was new to the state. There is also Pycnanthemum virginianum growing there, but the two look very different.

    You may want to check your mustard again. The fruit shown in the photo are too long and narrow for Rorippa palustris.

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  2. Thanks for you comments, Scott. I saw at least one Pycnanthemun species, but since it was mostly past flowering I didn't try to key out the species. Next summer I'll try to find both P. vericellatum and P. virginianum.

    Do you think the mustard is another genus or just another species of Rorippa? What key might I use to check it out? Amateur as I am, I've been using primarily Newcomb's Guide to Wildflowers and Kay Yatskievych's Field Guide to Indiana Wildflowers.

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  3. Hi John. Tough to say on the mustard from the photo. Maybe a Sisymbrium? I would suggest Plants of the Chicago Region or Manual of the Vascular Plants of the Northeastern United States and Adjacent Canada to try to figure it out. If you looked up Rorippa palustris photos online, I think the photos on Wikipedia are incorreclty ID'd. The photos at http://www.delawarewildflowers.org/plant.php?id=1710 and http://www.illinoiswildflowers.info/wetland/plants/marsh_ylcress.htm seem to be correct.

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  4. Thank you very much for this information, Scott. After looking at the USDA Plants Database and the Deleware Wildflowers site, Sisymbrium seems to me to be the most likely genus, but as you note, the picture alone is not enough to say for sure.

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  5. A year later, I have some identification corrections-- The Mustard I called Marsh Yellow Cress, Rorippa palustris, is more likely Eurcastrum gallicum and is introduced, not native. The Blazing Star is Savanna Blazing Star, Liatris scariosa var. nieuwlandii. The "Ohio Goldenrod" is probably Riddell's Goldenrod. Solidago ridellii and "Showy Goldenrod" may actually be Old-Field Goldenrod, S. nemoralis.

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