Waterlogged fields a season long challenge: OMAFRA specialist

Friday, June 3, 2011

by BETTER FARMING STAFF

Weather has gotten in the way of planting, now some farmers are seeing crusty soil conditions getting in the way of plants.

OMAFRA soil management specialist Anne Verhallen has been seeing some examples of crusting in the Chatham-Kent, Essex County area near Ridgetown where she works.

“When you get into the clay types and clay loams — anything with a fair bit of silt in it will tend to crust,” Verhallen said, adding crusting happens typically in soils that have structural problems.

“This year, however, there’s a couple of things going on,” she said. “We had an extended wet period. Some areas received significant pounding rainfalls . . . you’ve got a lot of energy hitting the ground and breaking soil aggregates apart.” She said when areas of a field hold water for a period of time they tend to hold water for the entire season, especially if they are not tilled.

Verhallen said Ontario soils are mixed. “What will happen is flowing water will take all these ‘blow apart’ (by the impact of the rain) pieces away.” As the water heads for the low spots, sand drops out as soon as the water slows. When water ponds a little, silts drop out over a couple of hours. Clays stay suspended for a while and drop out to form a seal that will keep soils wet for much longer.

“The next time you get rain,” she said, “it creates a vicious cycle that just keeps going.”

The short-term remedy is tillage. Verhallen said she has been seeing some corn being replanted and tomato farmers who are either cultivating or using a rotary hoe “just to open up the soil and allow the crust to breathe a little bit better because it really has sealed.”

While tillage will help get you through this season, Verhallen recommends a longer-term solution.

“Take a look at how you’re managing things,” she said. “Can you get some reduced tillage? Can you go to a no-till system? Can you make sure there’s more residue? Can you do a better job of rotating crops to try and grow soil structure?” BF