Morning glory can be a problematic weed for many growers, with it being a significant issue in the San Joaquin Valley. Seeds can remain viable in the soil for long periods of time and once the weeds have matured to a certain point, they are difficult to address without negatively impacting the crop. Crop Consultant with California Ag Solutions, Cary Crum said that implementing a cover crop system can be an effective tool in fighting the weed.
“Specifically processing tomatoes. They battle with morning glory and have for years. It’s becoming a losing battle because morning glory is terribly resistant to most of the chemical controls,” said Crum. “A lot of the growers are going back to doing a combination of chemical and mechanical controls and they’re beating their soil up pretty good trying to get the morning glory under control.”
Working with a tomato grower in the Central Valley, Crum noted they were able to have significant success in mitigating weed pressures with a cover cropping system. When comparing fields that had a cover crop to the standard control the grower was implementing, weed pressure was substantially lower in the field with the cover crop. On top of keeping weeds under control, Crum explained that cover crops provide “the added benefit of improved soil health, maintaining the soil biology, improving overall soil organic matter, improving cycling and nutrient cycling. All while that ground is in fallow state.”
Cover crops can also be more cost effective than chemical and mechanical mitigation efforts. Crum said that disking and herbicide applications to address the morning glory were costing upwards of $200/acre. In the trial field, the cover crop system was approximately half the cost. “What we’ve had to do with growers is get them to see the problem differently and put some competition into that system that allows that morning glory to break up its cycle. It seems to be working pretty well,” Crum noted.