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| VOLUME 2 |
ISSUE 2 |
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SUMMER 1992 |
IS IT NATIVE OR NOT?
Mention the use of a variety of native warm season grass to some people and stand back as the garlic necklace, wooden stake, cross and silver bullets are shoved into your face to fend off this threat to their purist idea of native vegetation. Many people have the idea that varieties are a manifestation of biogenetics to create a Frankenstein of native vegetation.
I recently discussed the process involved in developing a variety with Steve Bruckerhoff, conservation agronomist, at the USDA Plant Materials Center in Elsberry, Missouri. It just so happens that they are in the process of developing a new release of big bluestem and although the process for each new varietal release can be quite different this is what I learned about the one they are working on.
Plant breeders were looking for a big bluestem variety adapted to the Ozark region of southern Missouri and northern Arkansas. Of the varieties currently available leaf rust has been a problem so they were particularly interested in developing a new variety which is rust free. To develop a variety adapted to their target area they wanted collections of native plants from the region. From there they sent out the call to SCS district conservationists in 95 counties in Missouri, Arkansas, eastern Oklahoma and southern Illinois and asked each one to submit 4 non-related vegetative samples to them. This provided plant material from nearly 400 widely distributed sites creating a wide genetic base.
The plant material was divided up in the greenhouse and readied for planting. Inthe spring, plants were planted in a space planting at three foot intervals over 2 acres. It usually takes at least 2 years to nurture these plants back healthy enough to make evaluations for further refinement. Out of 4000 plants, 74 different plants were selected which exhibited the desirable characteristics and marked to be moved during the dormant season. These are the plants which are to be the parent material for propagation by seed. Up until now everything has been done vegetatively and any cross pollination in space plantings has no effect on the outcome. At this point the chosen few were planted in a crossing block so they can cross pollinate. Each seed was 1/2 the parent plant and 1/2 the 73 other plants. A researcher has 2 options to continue on. Depending upon a number of variables, and the least common option, the crossing block can become the breeders block. Seed from the breeders block is planted and propagated for several generations for eventual release. At Elsberry they chose the second option known as recurrent selection. Seeds from the crossing block were planted back to a space planting. From the space planting, plants were selected with the desirable characteristics and once again moved to a crossing block. This process can be repeated as many times as the breeders think is necessary to refine and preserve the characters they are wanting.
In order to release a new variety plants must be propagated from successive generations of seed for four years. Plants in the fourth generation must show the characteristics the variety was originally selected for before it can be released as a new variety. The entire process can take up to 15 years. In some instances, unlike the Ozark adapted variety of big bluestem, a varietal release will be derived from plant material from a single collection or from a specific region.
Depending upon the requisites you are looking for, a variety may or may not fill the bill. Varieties are no doubt "native" due to their source material but may or may not be of a local genotype. The bottom line is that you shouldn't write off the use of a variety without at least checking into its history.
| Common Name |
Cultivar |
Origin |
Year of
Release |
Big Bluestem
Big Bluestem
Big Bluestem
Big Bluestem
Big Bluestem
Sideoats Grama
Sideoats Grama
Sideoats Grama
Sideoats Grama
Sideoats Grama
Switchgrass
Switchgrass
Switchgrass
Switchgrass
Switchgrass
Switchgrass
Little Bluestem
Little Bluestem
Little Bluestem
Indiangrass
Indiangrass
Indiangrass
Indiangrass
Indiangrass
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Bison
Bonilla
Kaw
Niagra
Rountree
Buffe
El Reno
Haskel
Trailway
Vaughn
Alamo
Blackwell
Cave-in-Rock
Kanlow
Nebraska 28
Shelter
Aldous
Cimarron
Pastura
Lometa
Osage
Rumsey
Tomahawk
Cheyenne*
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Oliver Co., ND
Bonilla, SD
Riley Co., KS
Erie Co., NY
Moorehead, IA
Holt& Platte Cos., NE
Canadian Co., OK
Haskell Co., TX
Holt Co., NE
Guadalupe Co., NM
Frio River, TX
Blackwell, OK
Southern IL
Wetumka, OK
Holt Co., NE
Pleasants Co., WV
Flinthills, KS
Western KS, OK
Pecos, NM
Lometa, TX
KS, OK
Jefferson Co., IL
ND, SD
Supply, OK
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1990
1987
1950
1986
1983
1958
1944
1983
1958
1940
1978
1944
1974
1963
1949
1987
1966
1979
1963
1981
1966
1983
1988
1945
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| * Informal Release |
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