Sustainable Agriculture – A Plant Out of Place

How much yield is enough?

August 28, 2016February 15, 2018 - by Andrew Kniss

Last week, two colleagues and I published a paper in PLOS ONE titled “Commercial crop yields reveal strengths and weaknesses for organic agriculture in the United States.” The article presents an analysis of USDA crop yield data to compare organic and conventional farms in the US. We were pretty careful in the paper not to overstate our conclusions, since our goal was simply to see where organic yields were competitive (or not) with conventional crop yields. I explain more about …

The role of reflected light quality in crop-weed interactions

December 15, 2015February 15, 2018 - by Andrew Kniss

This post is a slightly edited excerpt from an article we wrote for Reflections magazine. Plants need light – this is one of the first biology lessons children learn in school. Plants convert sunlight into forms of energy the plant can use to grow. Nearly everything humans eat is derived in some way from photosynthesis, whether the tomato picked from a garden or a ribeye steak that once grazed on grass. Sunlight seems like a plentiful enough resource, but there’s …

The cost of preventing herbicide resistance

November 16, 2015February 15, 2018 - by Andrew Kniss

In my last post, I reviewed some recent research that suggests one of the best ways to delay the evolution of herbicide resistant weeds is to use mixtures of effective herbicides. Resistance is initially a very rare trait within a weed species, so the probability that any particular individual plant will be resistant to two herbicides is extremely low. The second herbicide is likely to kill any weeds that are resistant to the first herbicide, and vice versa. The theory behind this practice …

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 …

On transparency, intimidation, and being called a shill

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

A while back, a group of scientists involved in research or communication about various aspects of biotechnology (GMOs) were the subjects of freedom of information requests. Keith Kloor, who broke the story in Science, also posted one of the letters sent to the University of Illinois. The request asks for all emails in the last 2+ years between the scientists and a long list of companies. Gary Ruskin, an activist funded by the Organic Consumers Association, is making these requests while suggesting the …

A 40 year veteran of weed research reflects on his career

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

Bob Wilson, the weed specialist at the University of Nebraska’s Panhandle Research & Extension Center is retiring this month. Dr. Wilson has been a long-time mentor to me, serving as advisor for my M.S. and co-advisor for my PhD. Since then, we’ve collaborated on many projects aimed at helping sugarbeet producers better manage difficult weeds. UNL’s Crop Watch has a really nice writeup today about some of his career highlights. He discusses some of his thoughts about changes in weed …

Defining Agroecology

May 20, 2014February 15, 2018 - by Andrew Kniss

Agroecology (ag´ rō i kol´ ə jē), n. An ecosystems approach to agriculture. Agroecology. It’s an unfamiliar term to many people. And even people who are actively engaged in some aspect of agroecology sometimes disagree about what it means. I have to admit, even though the term is pretty important to me, I was fairly oblivious (or at the very least, indifferent) to the ambiguity until very recently. But it seems more and more I find myself trying to define …