superweed – A Plant Out of Place

Want to reduce herbicide resistance? Spray more herbicides!

October 27, 2015February 15, 2018 - by Andrew Kniss

A while ago, I wrote a post summarizing the pros and cons of using a regulatory framework to slow the evolution of herbicide resistant weeds. As a part of that post, I suggested there exists a “resistance management paradox.” In a nutshell, to reduce the problem of herbicide resistant weeds, one important strategy may be to actually use more herbicide. From my previous post: “The only way to assuredly prevent herbicide resistance from evolving is never to apply the herbicide; but if we are going to …

What does Chipotle’s switch to non-GMO ingredients mean for pesticide use?

May 18, 2015January 30, 2019 - by Andrew Kniss

A couple weeks ago, Chipotle announced they were removing genetically engineered crops (called GMOs) from their menu. Kind of. As you might expect, the announcement was covered widely in the media. Interestingly, though, most of the coverage wasn’t very positive. There’s a fairly long list of responses to the Chipotle decision if you’d like to read more about it. A variety of issues are covered in those responses, but I wanted to take a deeper look into the impact this switch might …

Superweeds: A Mutating Problem

October 8, 2014February 15, 2018 - by Andrew Kniss

Superweeds have been in been in the news a lot over the last few months. Most of the recent coverage has been related to new 2,4-D resistant crops that were recently approved by the USDA and the new herbicide formulation (2,4-D plus glyphosate) that the EPA is reviewing. Marc Brazeau recently wrote a compelling piece arguing that our focus on superweeds in GMO crops draws attention away from solutions that could really help make modern agriculture more sustainable. I’ve written about …

Regulating Herbicide Resistance

June 23, 2014February 15, 2018 - by Andrew Kniss

A few months ago, I wrote about 2,4-D resistant corn and soybean. At that time, the USDA had just completed it’s draft environmental impact statement for the two crops. While the USDA regulates crops developed through biotechnology, it is the EPA that regulates pesticide use. So before the new formulation of 2,4-D can be applied to the new corn and soybean varieties, it will need to be approved for use by the EPA. The comment period for the 2,4-D draft …

Fitness of herbicide resistance genes revisited

March 22, 2014February 15, 2018 - by Andrew Kniss

Last August, an article was published in New Phytologist that claimed a transgene added to rice could increase the fitness of a weedy relative. The paper was covered in the media pretty widely. When I read the paper, I didn’t think the authors presented nearly enough data to support their conclusions. You can find my criticisms in detail here. I think it is worth revisiting this paper now for a couple of reasons. The first is that two formal criticisms …

Large-scale impacts of herbicide-resistant weeds

December 2, 2013February 15, 2018 - by Andrew Kniss

As I was updating information on herbicide resistant weeds for class this week, I wanted to find some hard numbers on the large-scale impact herbicide-resistance can have. Obviously, my first thought was to find information on cotton production in the South. Glyphosate-resistant Palmer amaranth has been something of a poster child for the potentially devastating impacts of herbicide resistant weeds in the last few years. It has been dubbed a “superweed” by many, including Nature News, the New York Times, …

Managing herbicide-resistant weeds

November 10, 2013February 15, 2018 - by Andrew Kniss

I made this word cloud in preparation for the class I’m teaching tomorrow. I thought it was pretty interesting, so I decided to post it here and share. In class, we’re going to discuss the effectiveness of various practices to manage herbicide resistant weeds. In preparation for tomorrow’s discussion, I asked my students to review 5 different herbicide industry websites to see what they were recommending to manage herbicide resistant weeds. This word cloud was created by taking recommendations from …

Could a herbicide-resistance gene provide fitness benefits in the absence of the herbicide?

August 22, 2013February 15, 2018 - by Andrew Kniss

A really interesting study was reported by Nature News, and has been picking up steam around the interwebs (including Wired and Scientific American). The headlines read “Genetically modified crops pass benefits to weeds” and “weeds get unintended ‘fitness’ boost from genetic modification.” The stories are reporting on a study in New Phytologist titled “A novel EPSP synthase transgene for glyphosate resistance stimulates growth and fecundity in weedy rice (Oryza sativa) without herbicide.” Sorry, not open access. I’ve read the paper a …

Laurie Garrett gets things surprisingly wrong on the Colbert Report

June 6, 2013February 15, 2018 - by Andrew Kniss

Strange times indeed. I woke up this morning to find several folks in my twitter stream alerting me to an interview on the “Colbert Report.” The interview was supposed to be about the GM wheat found recently in Oregon. Near the beginning of the interview, Colbert asks (humorously) how the GM wheat survived, wondering if it had been “doing a Rambo out there, living on mud puddles and grubs?” Laurie Garrett immediately goes completely off-topic and responds: Garrett: “The one thing …

Where are the super weeds?

May 1, 2013February 15, 2018 - by Andrew Kniss

In a recent issue of Nature, Natasha Gilbert took “A hard look at GM crops.” Ms. Gilbert states: “it can be hard to see where scientific evidence ends and dogma and speculation begin.” “Researchers, farmers, activists and GM seed companies all stridently promote their views, but the scientific data are often inconclusive or contradictory. Complicated truths have long been obscured by the fierce rhetoric.” I agree wholeheartedly. Especially when browsing the internet, there is a lot of misinformation, half-truths, and …