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ISU Daily Article

Discovery Changes Herbicides

by Cara Turner

Originally Published in the Iowa State University Daily, Jan. 13, 1999

There have been many discoveries made that will change the way that we live and treat our environment, but the most amazing may be the ones that were discovered by accident.

This is what happened to Nick Christians, a professor of horticulture at Iowa State University. From an offshoot of another experiment, in 1986 he discovered a natural pre-emergent herbicide that is made out of corn gluten.

Christians says that the objective of the experiment was to study the effects of a fungal organism known as Pythium on creeping bentgrass, which is a grass used on golf course green.

In the field I had corn meal with Pythium, the next I had plain corn meal, and the third had control with nothing on it. Grass was seeded over the entire area and the plot with pythium was supposed to be dead, but it wasn’t, said Christians.

Normal germination of creeping bentgrass occurred in all of the plots, but in the plots with fresh corn meal, germination of creeping bentgrass had been reduced. Christians then got a series of corn components, which were starch , gluten meal(protein fraction), protein, and fiber, to see if the active component was in one of these. After a series of tests, Christians found that the active component was in the protein fraction of the corn gluten meal, which is a byproduct of the corn wet-milling process.

This corn gluten herbicide works because there are some natural chemicals in it that inhibit root formation at the time of germination, says Christians. The timing of application if very important for this to work. You have to apply the herbicide before the weeds germinate.

Mary Kleis, manager of technology licensing at ISU, says that corn gluten is the same thing that is in animal feed.

Dr. Kenneth Kirkland, director of the Office of Intellectual Property and Technology Transfer, says that the corn gluten herbicide has an exemption from the Environmental Protection Agency. It is safe, natural, you don’t have to worry about kids, and no toxicology tests had to be done on it. It is really unique that he did this, says Kirkland.

This is the only natural product marketed for weed control, says Christians, and it seems to be well-accepted.

Kleis says that there are sometimes legal reasons to use the natural herbicide instead of chemicals. There are parks in flood plains that people are concerned about using chemical herbicides on, and this is safe says Kleis.

Warren Jensen, owner of Safe Earth, Lawn, and Garden Care, Inc., says that it depends on why people purchase the herbicide to predict how pleased they will be with it. People that are environmentalists have one perspective, while people who want the product to work as well as chemicals may have another reaction. People who expect the natural herbicides to work as well as chemicals may be disappointed, says Jensen.

This is going well so far, says Jensen. People just have to be exposed to the corn gluten herbicide. A lot of the people that use the products have a concern for the environment and personal safety.

Jensen says that the products work differently than chemicals. Chemicals kill the weeds, while the corn gluten prevents establishment of a root system.

Kleis uses the corn gluten herbicide and she thinks that it works well. It Ìs just as easy to use as chemicals, says Kleis, and my dog enjoys licking it off of the lawn after it has been applied.

Christians says that the herbicide works on a variety of broad leaf and grass seed weeds. Crabgrass is the primary target, but it also helps to inhibit dandelion and clover at time of germination. Since it contains ten percent nitrogen, it helps with the greening of grass. It can also be used as a weed and feed, which means that it both kills germinating weeds and stimulates the growth of established plants.

You can do a better job quicker with chemicals and they are less expensive, says Christians, but this is a natural material and it is safe for kids, dogs, and the environment. Chemicals have an edge, so they will probably never be as good. They have been around longer and they continue to become more advanced. They can also be put into a more concentrated rate.

Research is being done to make the products more effective. Christians says that lots of work is being done by organic growers with products such as garlic, radishes, carrots, cotton, sugar beets, ginseng, and soybeans. There are a lot of materials out there with potential for pesticides, says Christians.

Research is also being done here at ISU. There is work being done on strawberries and the sprayable corn gluten items. It (sprayable corn gluten) is very effective in the lab, but not as effective in the field, says Christians, Ïbecause we have to find ways to stabilize it. Christians says that he doesn’t believe that the corn gluten meal will change the future of chemicals, but he does see an increase of interest in naturally occurring material for the substitute of pesticides. Gail Nonnecke, professor of horticulture at ISU, says that she does think that the corn gluten herbicide will change the way that we live because growers and consumers want to have benefit to the environment. Nonnecke believes that the demand will increase in the future. Nonnecke also thinks that this will change the way that herbicides are used. Within horticulture there are many growers producing organic fruits, vegetables, turf, and lawns that would be happy to use corn gluten meal because of its nitrogen and weed control, says Nonnecke. There are a few hazards of the chemical herbicides if they arenÌt applied correctly. Nonnecke says that if the chemical herbicide isnÌt applied properly it could end up in water runoff and go into surface water, such as lakes. A herbicide could also end up in drinking water or move with soil erosion, says Nonnecke.

There are three patents on Christians discovery. The first is the only one that is licensed and the other two are derivatives of the corn gluten meal, says Kleis. Christians says that the first patent is for corn gluten meal as a pre-emergent herbicide, the second is for corn gluten hydrolysate, which is corn gluten meal spray, and the third patent is for the natural chemicals that are responsible for the activity.

Kleis says that the patent cost figures are not available, but that they generally cost from $8,000 to $10,000. The ISU research foundation buys the invention from Christians, so the foundation owns the discovery and pays for the patents.

The research foundation also issues the licenses, which go to companies that are going to make the products out of Christian’s corn meal gluten herbicide. These companies then have to pay the university a percentage of their royalties. Christians gets a percentage of the universities royalties.

So far there are 17 licenses, says Kleis. There are also several companies inquiring about the licenses. Christians says that the corn gluten herbicide is already marketed nationwide and hopefully it will expand in sales. According to Kleis, over one million dollars in sales of corn gluten meal herbicides have been made in 1998.

These products are sold in Iowa. Christians says that the companies in Iowa that sell these licensed products are Safe Earth Lawn and Garden Care, Inc., Manning Agriculture Center, Soil Technologies, and Grain Processing Corporation. Gardens Alive W.O.W!, which stands for without weeds, is also on sale through mail order.

Some of the products that can be found around the United States are Earth Friendly, Safe ÎN Simple, Safeway, Green Sense, Suppressa, and Weedz STOP.

Christians also received Iowa Inventor of the Year on October 30, 1998. That was interesting, commented Christians. In 1996 he received an R&D 100 award, which is a national award for the top 100 new technologies of the year. Both of these honors were for his corn gluten herbicide.

I think that this will be a growing trend in horticulture, especially.

Crops we raise in horticulture are considered minor in comparison with row crops, such as corn and cotton. It has already started to change with horticulture producers looking for alternatives to chemical herbicides, says Nonnecke.

The corn gluten herbicide makes a big difference for those who don’t want to use chemicals, and that’s a growing number of people, says Christians.

Go to Iowa State University Horticulture Research Page

Go to Nick Christians/Faculty Page