Help eradicate spotted knapweed

Spotted Knapweed
Knapweed in the basal rosette stage. Step No. 1 for treatment of spotted knapweed is accurate identification. (Photo courtesy of

In the midst of self-isolation as suggested by our public health experts, I find myself daydreaming about happy times with people I love, hoping that they are doing well and looking forward to gathering together again. One of those happy daydreams took me back to summer.

For our daughter’s birthday party in August, we had a homemade slip and slide in the backyard. The year before we had a slip and slide, which provided hours of fun, but needed significant improvement.

So, when she turned four, we got serious about it. The slide needed to allow for enough speed and stopping power for kids and adults alike to have a good time. We installed an overhead sprinkler, acquired plenty of soap, and my husband designed an excellent barrier for the end of the slide. It would prevent you from careening off into the woods and create a pool of water for a satisfying splash at the end.

What does this have to do with grazing? The title of this column, after all, is “All About Grazing.” Hang tight readers, I’m getting there.

Hay bale barriers

The critical building material he needed to gather to create the barrier was bales of hay or straw. We don’t have people around us who grow small grains, so hay is was the more convenient option.

A fellow my husband works with had some square bales he gave us for free. It was some of the worst hay he has ever made, and he was happy to be rid of it. Perfect for our situation, since we planned to completely destroy it by the end of the party, rather than feed it to livestock.

Much to our surprise, the hay bale barrier held up amazingly well. Even with a barrage of full-grown men cruising down the slope and smashing into them. They were covered with a tarp to keep the water in the pool and prevent skin irritation. We were surprised by how dry they were when we tore down the slip and slide and decided to keep them as bedding for the hens at our place this winter. Any concerns with this plan?

Spotted knapweed

A couple of the bales did get moldy after being stored, which we were on the lookout for, but the more concerning thing was, I believe they had some spotted knapweed in them.

In our neck of the woods, spotted knapweed is at the top of our hit list as a newly invasive weed. It is an aggressive biennial (sort-of) forb with similarities to Canada thistle and chicory. It does not flower in the first year of growth and therefore is often missed in year one. It crowds out other beneficial plants, thriving on marginal sites, creeping into hayfields and blanketing highway berms and medians.

Last March in this column I wrote about gearing up for spotted knapweed control. We are still raising awareness and encouraging the removal of spotted knapweed upon discovery. Along with traditional education about pasture management and weed control, additional help is available for landowners who spot spotted knapweed on their property.

The Spotted Knapweed Treatment for Ohio Producers (STOP) Project is funded through the Regional Conservation Partnership Program (RCPP), which is administered by the Natural Resources Conservation Service (NRCS). Landowners of Noble, Guernsey, Muskingum and Morgan County are eligible to apply for cost recovery funds to treat spotted knapweed in pasture and hayfields.

County soil and water districts and OSU Extension are active partners in the program. We hope to increase awareness of spotted knapweed in our landscapes and provide educational resources on how to control its spread.

On the lookout

Like our reliable public health experts keep reminding everyone to wash their hands to slow the spread of COVID-19, I am here once again to remind you to keep an eye out for spotted knapweed. As things warm up this year, I will be scouting the island around our chicken coop, our manure compost area and the slip and slide splash pool prior location for knapweed seedlings.

I am not 100% sure that what I saw was spotted knapweed in that hay, but it came from an area on the county line where populations are already high. If it wasn’t knapweed, it was Canada thistle and I don’t want that either.

The good news is that knapweed is responsive to multiple broadleaf herbicides. Mowing is marginally successful. It does help prevent the development of seed, but it is often able to flower below the height of the mower deck. Chemical treatment has been successful in grass pastures of our region if timed appropriately. There are biological controls being developed for spotted knapweed too, but they are primarily sourced from the Western States in high demand.

Therefore, in May I will start watching for the characteristic basal rosette of spotted knapweed and terminating it on first sight by whatever legal means necessary. In my situation, hand pulling will probably be step one. If that doesn’t cut it, we will try a broadleaf herbicide in combination with frequent mowing.

If that doesn’t work, I will take a wildflower walk with my daughter and pay her a penny for every magenta flower she can find and pick. We will gather them all up in a vase and let them die on the table. If you live on the Eastern side of Ohio, I suggest that you also keep watch for knapweed in areas along roadsides and places where you have fed hay this winter.

Two common sources of initial seed are roadside mowing and transported hay. As with any infection, the best tools for control are early detection and early action. Hand pulling and spot spraying young plants that are few and far between can be effective on new invasions.

However, heavy infestations will likely take a more creative and lengthy approach to treat. You can learn more about spotted knapweed in Ohio on YouTube. Extension educators Clifton Martin of Muskingum County and myself broadcasted an informational interview about spotted knapweed as part of a video series called “Forage Focus” in September 2018. It can be viewed at

Familiarize yourself with this invasive weed so that you can become part of the solution to stop the spread of spotted knapweed. Train yourself now so that you don’t find yourself two years down the road asking, “Where’d this knapweed come from?”

If you come across something you suspect might be spotted knapweed, please contact your county extension office for assistance with identification. To learn more about the STOP Project or to submit an application, visit your local USDA Service Center or visit the NRCS website and select “Get Started with NRCS.”

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