Jim Patton bends down and scrutinizes the miniscule green leaves barely poking through the Mad River Valley soils on his West Liberty, Ohio, farm.
“You can use quarter rates of herbicides with 1-inch lambsquarter. But if the weeds get over 2 inches tall, quarter rates won’t control the weeds,” he says comparing the tiny weeds. The 2-inch tall lambsquarter requires half rates.
Inches equal dollars when it comes to reducing labeled herbicide rates. Patton strives for half to quarter rates with post-emergence soybean herbicides. Cutting herbicide rates saves $8 to $10 per acre.
Although slicing labeled rates saves dollars, the practice requires precise management with no-till. “You have to be out there scouting,” Patton points out. After using reduced rates for 6 years, Patton shares some pointers:
1. Companies won’t stand behind the products if labeled herbicide rates are not used. “You’re on your own,” Patton warns.
2. Read the label to find the herbicide’s strengths and weaknesses.
3. Find out if the label specifies a crop oil or surfactant.
4. Watch the weather forecast and temperatures. The weather can greatly influence post-emerge herbicide performance, he adds.
Mark Loux, Ohio State University weed scientist, recommends avoiding post-emerge applications during abnormally cold conditions. That’s because many herbicides are less effective when night temperatures drop below 45 to 50 degrees.
In dry weather, weed control is even more challenging. Loux recommends adjusting the herbicide rate and type of adjuvant to increase activity, applying grass and broadleaf herbicides…