Monday, July 12, 2010

Ditching for Local Grass Seed

Each year I've started to watch the progress of the native grass seed in the ditches with one eye, while I watch the county mowing crews with the other eye. Last year the mowers reduced the native grasses to stubble well before any seed was ready, but this year the balance of the two has worked out better for me, at least so far.

One of the grasses I've been particularly eye-balling in our local ditches is eastern gamagrass (Tripsacum dactyloides). I believe this grass is one of the ones being used by Wes Jackson at the Salina Land Institute in his quest for perennial grain crops. It's related to maize (corn) and the seeds are much heftier feeling than those of most of the other grasses.


Eastern gamagrass is a majestic grass, growing in large, bright green clumps, with seed stalks as high as 9' tall. Although it's considered a warm season grass, it seeds much earlier than most of the other prairie grasses. The photo above is a clump of eastern gamagrass in a ditch just south of our home.


Gamagrass flowers are either male or female, but both male and female flowers are found on the same flower stalk. Better yet, they are very neatly arranged, with the female flowers at the base of the stalk and the male flowers at the upper end. (The photo above shows the male flowers in full bloom. You can see the (bare-looking) female flowers at the very bottom of the flowerspike.) Once pollination has occurred and the male flowers' job is done, the male part of the flower spike falls off, leaving just the beefier female flowers, now turning into heavy, fertilized seeds, as you can see in the photo below.


Because it likes dampish soils, eastern gamagrass is naturally found between prairie cordgrass (Spartina pectinata, which is also known as sloughgrass) and switchgrass (Panicum virgatum) in a wet to dry continuum. It's a perfect ditch plant! I had never seen a lot of eastern gamagrass until moving to Sedgwick County. Here, in this flat land along the Arkansas River, it is not uncommon along the roads and must have once been common in the local prairies. It is highly palatable to cattle and gets grazed out quickly in native pastures, which easily explains why I don't have any in my poor little overgrazed pasture.

So, I'd love to get this species reestablished. Our back 5 acres should be perfect for it, as we have several low areas that hold water for several days after a rain and that have sedges growing in them already.

I've been noticing on the nearby clumps of gamagrass that the male flowers have fallen off the flowerspikes and the seeds are turning brown, so I got Prairiewolf and Becker to accompany me yesterday morning and we set out "ditching". It was, I think, just about perfect timing to do it. The gamagrass seed heads "shatter" (fall apart) very easily once they are completely ripe, so you can't wait too long to collect seed.

As I approached the first clump, I noticed a real mix. Some seed heads were already gone, having ripened and shattered, scattering the seed and leaving just the tall stalk. Most flowerstalks had lost the male flowers and the remaining seedheads were in various shades of green, brown and purple. A few flowerstalks were still in bloom.




I gathered only those seeds that were showing at least some degree of brown and that snapped easily off the flowerstalk. Prairiewolf took some photos (including the VERY unflattering one of me above) and later joined me in harvesting the seed. Becker sat watch nearby, almost lost in the other grasses in the ditch. Between the three of us, we were able to get a full cookie-sheet's worth. I'm letting the seeds dry out a bit, then on the next reasonably pleasant day, I'll scatter the seed and keep my fingers crossed that I'll see eastern gamagrass in our recovering prairie within a few years.


3 comments:

~Gardener on Sherlock Street said...

I wish you much success establishing the grass in your area. I'm sure the wind nabs those seeds as soon as they're dry and spreads them everywhere. You had good timing.

Gaia Gardener: said...

Actually, for eastern gamagrass I have to guess that rodents or birds or maybe water are the movement vector. Unlike most prairie seeds, these seeds are much too heavy to do more than fall directly to the ground.

Thanks for the good wishes on rehabbing our prairie. Success is far from guaranteed, but it sure is fun!

Mother Nature said...

Good luck with the grass project.