Ken Lassman: Lawrence Parks and Rec is downplaying herbicidal overkill of remnant prairie (Column)

Share this post or save for later

Note: The Lawrence Times runs opinion columns and letters to the Times written by community members with varying perspectives on local issues. These pieces do not necessarily reflect the opinions of the Times staff.

Want to submit a letter or column to the Times? Great! Click here.

On Thursday, April 27, the Lawrence Parks and Recreation staff sprayed the entire 5-acre old growth prairie next to the Prairie Park Nature Center with a systemic herbicide called PastureGard. I found this out by going to the prairie on Sunday, as I usually do, to observe which wildflowers were blooming or about to bloom. I include this information in my weekly nature guide, the Kaw Valley Almanac, which I have been doing for around 20 years and have been visiting the prairie for decades before that.

But nothing prepared me for the shock and devastation that hit me when I arrived on Sunday to see the entire prairie curling up in the throes of herbicide-induced plant death. 

You can read more of the details of this tragedy in the various available news accounts published Monday. My aim here is not to recount those details; I am writing this because I am extremely concerned about the nature and tone of the press release provided by the Parks and Recreation Department and want to point out in no uncertain terms that its tone shows serious flaws about what just transpired. Its downplaying attitude does not acknowledge the severity of the missteps or the potential problems with continuing to think in the same ways that made this miscalculation possible.

The email released Monday by Parks and Rec titled “Controlling noxious weeds, invasive species at Prairie Park” seems to be implying that the boom spraying of a systemic herbicide on the entirety of this 6,000-plus year old plant community is standard protocol for effectively managing existing noxious and invasive species present in the vicinity of the unplowed prairie. Nothing could be further from the truth, and this basic mismatch between the problem and their solution points to a much more serious problem than the weeds. Let me expand a bit.

PastureGard is a systemic herbicide that contains two chemicals, triclopyr and fluroxypyr, both of which are chemicals that mimic auxins, a type of growth hormone found in all broadleaf plants, such as the target invasive weed sericea lespedeza but also every native wildflower/forb present in the prairie that has emerged this spring. Any sprayed plant rapidly takes in these chemicals through leaves and roots. It causes uncontrolled plant growth and plant death.1 

After absorbing the herbicide, plants die slowly (within weeks). By carpet spraying the entire prairie, no distinction was made between the few patches of the invasive sericea plant and the over 100 native “forb” (wildflower) species that had lived on that land for thousands of years. This despite the herbicide label clearly stating: “Do not use on bentgrass, alfalfa, or other desirable forbs, especially legumes such as clover, unless injury or loss of such plants can be tolerated.” Sadly, those few patches of sericea located mostly around the perimeter of the prairie had not even emerged from the ground yet, while many, many native forbs had either emerged or were already blooming, meaning that the target was missed entirely, killing the prairie plants instead. 

Even the press release states that “Our current plan is to return to a rotational management plan that includes mowing, burning and spot spraying to control invasive, woody plant materials and noxious weeds.” So why was the entire prairie soaked with herbicide instead of spot spraying the individual patches of invasive weed sometime in the future after it had emerged?

The press release continues by seriously downplaying this herbicidal overkill by saying that “Some early-growing, native plants have been affected; however, some of the established plants that have not yet emerged will not be affected.” A group of botanists from a number of institutions will be out there Tuesday afternoon trying to identify the dying plants this week before they become unrecognizable, to document the losses, but I saw numerous species of plants that don’t bloom until late summer that were fully emerged and curling up from absorbing the systemic herbicide.

Although it is too early to say what will survive and what will die, the impact will be long-term. Quite likely, the damage to the prairie’s diversity will be permanent. The spring wildflowers are some of the rarest and hardest to find replacement seeds for, let alone nearly impossible to introduce into an already existing prairie. Once again, Parks and Rec is seriously downplaying the unlikelihood of the prairie recovering after being so seriously damaged and depleted by this senseless act. 

There seems to be a fundamental lack of distinction between the common practice of spraying for weeds in a hay meadow and managing the incredible diversity found in a remnant prairie. Douglas County used to be around 85% tallgrass prairie. Now, less than one-half of 1% remains as native remnants. 

The City recognized the gem of this prairie remnant by preserving it and showcasing it by establishing the Prairie Park Nature Center. Last year, Douglas County funded an active restoration grant to expand the presence of native plant communities surrounding the old growth prairie, through the Natural and Cultural Heritage Grant program.

Parks and Recreation clearly lacks a culture or management plan that recognizes and effectively nurtures and values what native prairies and woodlands remain as is evidenced by this event and the responses to it. This can and should change, and it is up to the citizens of our city to ensure that such a robust plan be developed before this happens again.

— Ken Lassman is the author of Seasons and Cycles: Rhythms of Life in the Kansas River Basin in 1985, Wild Douglas County in 2007and curator of the Kaw Valley Almanac.

If this local platform matters to you, please help us keep doing this work.
Don’t miss a beat … Click here to sign up for our email newsletters

Related posts:


More Community Voices:


Click here to find out how to send a letter to the Times
  1. National Pesticide Information Center,
Previous Article

Advocates, residents concerned that ‘no visitors’ policy at North Lawrence camp is alienating

Next Article

Dogwatch: Meet Otto, Phoebe and Guy