Trials and Tribulations of Plant ID: Indiangrass

Jamie Bachmann, Wildlife Education, Northern Prairies Land Trust

I am a wannabe plant nerd.   I know some of my plants.  I forget some and relearn them every year.  Some I remember and are added to the list of plants I feel pretty darn confident naming. I have one of those curious brains that I cram a lot into but the recall is lack luster.  Currently out here on some parts of the prairie a lot of grasses are blooming and seeding.  It is a beautiful sight.  I went out to snap some pictures and focus in on a couple of key identification characteristics of Indiangrass.  Follow me on the quaking slope of self-confidence known as trying to ID a plant. I’m sure some of you know what I mean.

As best as I can tell, and from years of plant hikes with true blue plant nerds, a couple of characteristics a person wants to take a look at are the auricles and ligules. You can find these parts by pulling down gently on a blade of grass and peaking closely at the sheath that wraps around the stem.   The ligule clasps the stem right there where the blade and the sheath meet. The auricles are the little guys that stick out from the collar. Oh, yeah, the collar is like a shirt collar.  When you see it you will know what I mean.

auricle and ligule
Photo Credit

In indiangrass the ligules are ‘membranous’.  I don’t really know what that means, but we can assume right? The auricles ‘extend upward, are pointed and join the ligule’.   Let’s compare.  Looks about right.

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Left: Indiangrass leaf blade and ligule. Photo Credit: Jamie Bachmann Right: Indiangrass ligules and auricle. Photo Credit

 

 

indian grass auricle

 

 

 

 

Next I took a look at the spikelets.  Spikelets are the flowering/seed parts of the seed head.  I haven’t gotten much further than using the awn as an identifying characteristic.  The awn is the pokey hair-like guy that sticks out of the floret and is attached to the actual seed.

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Indiangrass seed head and awn. Photo Credit: Jamie Bachmann
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Indiangrass seed head with bent awn.  Photo Credit: Jamie Bachmann

An awn can be used as a seed dispersal mechanism or aid in getting that spikelet planted in the soil. Indiangrass awns are often bent.  Apparently, and to be more exact, “They are tightly twisted below the bend and loosely twisted above the bend.”   As fluctuations in humidity vary from day to night the awn will alternate between standing erect and slackening, “This movement allows some seeds to effectively corkscrew themselves into the ground.” Needle and Thread grass is a great example of this adaptation.  Check out that awn.  Plants are so cool!

needle and thread grass awn
Needle and Thread Grass Seed Awn.  Photo Credit:

For those of you on my end of the plant nerd spectrum I’m hoping this was helpful. Keep learning those plants.  Don’t let the science of it distract you, but instead lead you to awe and wonder.  For more information on grass identification check out this nifty little publication: http://extensionpublications.unl.edu/assets/pdf/ec170.pdf.

I would also like to thank my assistant who actually didn’t help at all to keep grasses from blurring out in my pictures.

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