He said people were heartened that the industry had been given the opportunity, through the intensive winter grazing group, to come up with some practical rules.
While there are no new rules yet, between now and May next year anyone who is doing new intensive winter grazing, or expanding the amount they previously did, will need consent from Horizons Regional Council.
Farmers have until October 31 to apply for consent, regulatory manager Greg Bevin said, and it can be granted retrospectively.
Winter grazing was about maintaining stock condition during the cold time of low pasture growth, Cranstone said.
In intensive winter grazing fodder crops are grown during the warmer months and grazed in the winter.
The most common crops in the Whanganui Region were brassicas and fodder beet, Cranstone said.
Farmers have a lot of tools they can use to prevent their winter grazing practices adding sediment and nutrients to waterways, compacting soils and forcing animals to stand ankle deep in mud.
Pasture growth is better in the warmer North Island. One of Cranstone's techniques is to apply nitrogen in autumn, get extra grass growing and leave it ungrazed until winter.
That has worked well in this year's good growth season.
"The hill country farmers up country to the north had a very dry autumn. There's extra challenges for them," he said.
He suggested grazing cattle on lighter soils near rivers in winter, because excess nitrogen was not a huge problem here.
"In Whanganui district our greatest winter water quality challenge is sediment."
People who are break feeding crops should start at the top of a slope or as far as possible from a waterway, and move progressively closer. The crop downslope can then capture sediment and nutrients before they reach water.
Any place where water runs off into waterways should be fenced off.
As stock move across the paddock they can be back fenced, Federated Farmers suggests, to keep them off ground already trodden.
They should always have dry places to lie down. Portable water troughs and feeders come in handy as they move across.
"It's all about doing the best for stock. Farmers want that anyway," Cranstone said.
Cranstone said he could avoid break feeding by harvesting fodder beet and storing it to feed out on dry soils later.
He said keeping heavy animals off saturated soil was not always possible, but it should be minimised because it compacted soil.
"A farmer's greatest asset is their soil. If you don't look after the soil it won't look after you."
Farmers would get better results from considering the soil types, contour and stock on their farm than from obeying rules, Cranstone said.
"Broad brush rules will not achieve the same as individual farmers understanding their own situations and being proactive."
