Early Summer Drought
It may feel to some folks that the current dry conditions have come on very suddenly but as is often the case with ecosystems, there is a degree of resilience built into our farm and forest land that can mask underlying problems until a combination of factors send the system across a threshold where it cannot function normally.
Our current drought actually started last year, reaching a peak in October when rains failed to materialize before a series of hard frosts took away the chance of any pasture recovery before winter. Precipitation levels through the winter were close to average and soil moisture levels mostly recovered but farmers endured a winter with very limited supplies of hay.
Above average warmth in March brought an early flush of green growth to Rockbridge pastures. But Rockbridge was a full inch short of the usual 3.5 inches of precipitation in March and April was .7 inch short of the 3.7 inches that is normal for April. Hay meadows went to seed early with relatively little leaf production. Farmers in Rockbridge have reported first cutting hay yields ranging from just a little short of normal to over 50% less than usual.
May again fell short on total precipitation, about one-half inch below the 4 inches of precipitation that is normal for May in Rockbridge. Three months of precipitation shortfalls and now an extended period of above-normal temperatures has baked fields that are normally a lush green this time of year.
So, what next? For livestock producers, they need to identify smaller “sacrifice” pastures to which they can retreat with their livestock. These fields need to have a sufficient water supply, preferably adequate shade, and accessible for reseeding with equipment after the drought breaks.
Where ever possible, livestock producers need to cease grazing all other pastures when grass heights get down to 4 inches on average. The reason is pastures need to have sufficient photosynthetic leaf material for the plant to recover once it does finally rain. Overgrazed pastures will be slow to recover compared to a pasture that has 4 inches of leaf area.
Seasonal evapotranspiration patterns tell us we may see some recovery and be able to maintain some topsoil moisture if we begin to get consistent rains that continue through the summer but subsoil moisture is unlikely to be restored to any significant degree until fall or winter.
Most farmers are short on hay and are hesitant to draw on limited hay supplies with not-so-good prospects for significant hay yields in the remainder of the growing season. But maintaining adequate body condition on all breeding and growing stock is fundamental to their productivity.
There are options for feeding commodity bproduct feeds and greatly limiting the amount of hay livestock are fed. Ruminants (cattle, sheep, and goats) require only a small amount of effective fiber to maintain proper digestive function. The rest of their dietary requirements can be met with pelleted feeds. As expensive as this practice may be, it is the better choice compared to allowing livestock to loose weight while they damage pastures to the extent the pastures will be slow to rebound.
For more information on drought management strategies, contact me, Tom Stanley, through the Rockbridge Office of Virginia Cooperative Extension at (540) 463-4734 or by email at [email protected].