In the 8-minute segment, which runs from about 23:50 to 31:30 in the hour-long show, Hanson outlined Cooperative Extension weed management research.
"Weeds are a tremendous problem for farmers in every cropping system," Hanson said. "In contradiction to some other pests, weeds don’t spike. They are a constant problem. Farmers are spending money on weed control and trying to minimize productivity declines from weeds competing for water, fertilizer and sunlight."
Hanson said much of UC's weed research looks at chemical control, the approach used by 85 percent of farmers.
"We try to find the most efficient rates, most effective chemicals, and the least environmentally damaging products," he said.
Callison seemed intrigued by the fact that weed seeds can lie dormant in soil for years and even decades.
"It is said, one years seeding is 10 years weeding. That’s probably an underestimate," Hanson said.