Wildfires consumed hundreds of acres of range and pastureland in the western half of North Dakota this spring. Burned areas can continue to be grazed, but managers must take precautions and reduce stocking rates, says Kevin Sedivec, North Dakota State University (NDSU) extension rangeland management specialist. Here are some of his suggestions:
Delay the livestock turn-out date two to four weeks. Grazing should begin no earlier than late May for crested wheatgrass or smooth bromegrass and mid-June for native rangeland following an early spring burn.
Reduce stocking rates by 30-50% in the western Dakotas, 20-30% in the central part of the states and 10-20% in eastern areas. These reductions will be greater if dry conditions persist into May and June. Range and pastureland in the Dakotas, Minnesota and eastern Montana grow the majority of forage in May, June and July. If rain doesn’t fall during this period, plan for substantially less forage.
Use stage of plant development in determining forage-quality goals for hay production. If fire impacted your hay land, maturation will be delayed slightly, forage production will be reduced and forage quality will be improved. “Determine your forage-quality goal and harvest accordingly to optimize production and quality,” Sedivec says.
Past research in western North Dakota showed that, on average, dormant-season fire reduced forage production by 40% during the first growing season after the fire, regardless of grazing history. During the second season, production was reduced by 10% in a rotational grazing system and non-grazed areas, and 30% on season-long grazing pastures. “One interesting note is that these negative impacts on forage production occurred in a year when spring rainfall was normal to above normal,” Sedivec says.
Another trial in east-central North Dakota tested the impacts of spring fires on forage production of grasses and leafy spurge. Spring fire reduced grass production by 17%; however, leafy spurge production increased by 27%. Grass production was impacted only the first growing season following a fire, while leafy spurge production remained greater for two growing seasons. In both studies, plant species composition was not affected by a one-time fire event.
