Genetically Modified Bentgrass, Crop, Agricultural Weed, or Noxious Weed?

             Golf course managers would love to have Roundup-resistant bentgrass for their greens. It would make keeping greens weed-free simple and inexpensive. Just spray them with Roundup, and everything but the bentgrass dies. Roundup binds to organic matter and doesn’t persist very long, so it is less harmful to the environment than many other herbicides. Scotts and Monsanto successfully added a gene conferring Roundup resistance to bentgrass a decade ago. The United States Department of Agriculture (USDA) issued permits for trial plantings, including fields in Oregon and Idaho. So far, so good.

            Bentgrass is a perennial plant that is wind pollinated. It will cross-pollinate with some wild grass relatives. Due to concern that trials in the Willamette Valley could result in pollination and marketing problems, the Oregon Department of Agriculture (ODA) worked with Scotts to set up a control area for the genetically modified bentgrass near Madras 90 over the mountains. Some trial fields were also planted near Parma, Idaho. All of these trials were done under USDA permit. From a production point of view, the trials were a success, so Scotts and Monsanto petitioned USDA to deregulate the product so that they could start selling Roundup resistant bentgrass to golf courses. USDA’s review of the deregulation petition has been drawn-out and difficult, and it just got more complicated.

            Two irrigation districts in Malheur County, upwind and across the river from the Parma fields, were recently treating their canal banks with Roundup. All the weeds were dying except one type of grass.  Oregon State University (OSU) tested samples, and it had the Monsanto gene. Somehow the genetically modified (GM) bentgrass moved from Idaho to Oregon, and now exists up and down miles of irrigation canals between Nyssa and Ontario.

            Oregon’s regulations don’t apply, but this is a violation of USDA’s permit. Since it’s discovery, Scotts has been working to eradicate the GM plants along over 20 miles of canal bank.  I hope they succeed.  ODA has helped them identify legal and effective herbicides; there aren’t many – Roundup would normally be the material of choice.

            Longer-term, ODA will be faced with a dilemma. Is this grass just a crop that produces volunteers?  Is it an agricultural weed?  Or is it a potential noxious weed that will cross-pollinate with wild plants and compete with native plants? We don’t know. It is not clear whether we should simply keep our eye on it, or pull out all the stops and go for complete eradication.

            In the meantime, Scotts has set up a hotline (877-375-5139) to report sightings. Give them a call if you come across a low spreading grass that just smiles when you spray it with Roundup. Bentgrass needs plenty of water, so wet/irrigated areas in Central Oregon and downriver from Ontario would be the places to look. It will be interesting to see how this plays out. We could be playing golf on this grass or cussing at it.  Stay tuned.

Dan Hilburn