- 97% of samples contained viable weed seed
- Combine head samples contained
49% of the total weeds emerged, followed by the feeder house
If you are unable to remove weeds that have gone to seed, it is important to develop a sound harvest strategy to minimize the spread of weeds from field to field. This would include cleaning combines between fields and harvesting fields with severe weed infestations last.
Crop harvest is here and that means it’s time to be thinking about weed seedbank management. Over the last few weeks we have observed fields throughout Wisconsin with a fair amount of weed escapes. The most troublesome weeds in Wisconsin, waterhemp and giant ragweed, will retain their seeds well into October in the Upper Midwest. If you have weeds that have set seed in your field, now is the time to get out there, remove and burn them before combines start rolling. Check the “UW-NPM Weed Seed Management at Crop Harvest (PDF file)” handout used in our Combine Cleaning Workshops.
In total we received 31 samples from nine different combines (many thanks to all project participants). We then mixed the samples with field soil and potting mix in our greenhouse and observed what weeds emerged after two weeks.
Last fall, to validate our concerns of weed seed movement via combines, we put out a call to UW-Madison Ag Extension Educators and stakeholders to take the time to clean and collect samples from combines before putting them away for the winter. We specifically asked for samples from four locations: head, feeder house, rock trap, and rotor:
Here are some of the highlights:
Global Neighbor has received two rounds of funding, totaling nearly $900,000, from the federal government’s Small Business Innovation Research program to develop and test the NatureZap device.
When you think of military weapons, you tend to imagine things such as bullets and bombs. The Air Force is experimenting with a new tool for its arsenal: a wand that zaps a concentrated beam of light and heat.
This is the second version of NatureZap. The company previously sold a similar device, also called NatureZap, that only used heat to kill roots.
The electric device uses a combination of heat and high-energy blue light to kill the plants’ leaves and roots. Treated plants, according to manufacturer Global Neighbor, die in as little as three days. “We’ve had a pretty good success rate,” said Jon Jackson, the company’s president. “We get about a 70 to 80 percent die-back without regrowth.” He said NatureZap is particularly effective on ragweed, dandelions, and crabgrass. The light penetrates about two inches into the soil, so it only affects targeted weeds and not the “good” plants around them.
No, this isn’t Harry Potter, and the enemies aren’t terrorists. The wand is called NatureZap, and it targets “unwanted vegetation”—aka weeds. Edwards Air Force Base in Southern California is testing the device as a way to remove weeds without the use of toxic herbicides.
Danny Reinke, principal scientist for the 412th Civil Engineering Group at Edwards Air Force Base—who developed the device with Global Neighbor—told the Desert Wings newspaper that NatureZap may be useful in meeting the military’s requirements to reduce its use of toxic chemicals under the Sikes Act, which helps protect endangered species on Department of Defense property. He’s testing a battery-powered version of the device that reportedly can treat a softball field–size area between charges.
“We’ve graduated since then,” said Jackson. “Even before we were with Edwards we spent a few years working with lasers and other things, trying to get ground penetration.” The developers hit on the idea of light several years ago after they built a clear Plexiglas enclosure to see how their earlier device affected dandelion roots. “It turns out that’s a stupid idea because as soon as you expose a root to light it dies,” Jackson said.