Management Tips for Drought-stressed Forages22 March 2013
US - The Midwest U.S. has seen some of the most extreme drought conditions of recent memory. Some precipitation has come over the fall and winter for much of this area, but not enough for most of us to feel comfortable about, writes Steve Barnhart, ISU Extension forage agronomist.
Most pastures and many hay fields were in poor condition going into the winter. As you consider the following management options and practices, keep in mind that precipitation and soil moisture conditions are a very important variable in their effectiveness, and there will be weather risks overshadowing them.
Help recovering hay and pasture stands "catch up" and regain vigor in the spring: If fall recovery was not favorable, or you cut or grazed late in the season in 2012, the recovering forage plant may still be under some physiological stress.
Hay and pasture plants will benefit from allowing a bit more recovery and growing time this spring before they are cut or grazed. For best "recovery management" delay the first cut of alfalfa stands until they reach early- to mid-bloom. For pastures, allow 3 to 4 inches of growth in the spring before livestock turnout. Also consider reducing stocking rates on pastures until growing conditions improve.
Fertilizing pastures in the spring: From an economic and productivity standpoint, apply phosphorus (P) and/or potassium (K) only if they are needed! The need for pasture P and K are best determined by soil testing. Soil testing and needed applications can still be done in the spring.
Applying nitrogen in early spring is a common practice on many farms. Grass-based pastures usually respond quickly to added nitrogen.
From a management standpoint, however, consider whether you can actually use all of the extra pasture growth, or whether it will be more economical to apply a modest early spring application (30 or 40 lbs/Ac), and assess the precipitation probabilities for the remainder of spring and summer. You can apply an additional 30 or 40 lbs/Ac in mid-spring, and again possibly in late-summer to make your seasonal nitrogen use more efficient.
Repairing and reseeding - consider frost seeding or interseeding drought-thinned pastures or hay fields
Frost seeding is the broadcasting of legumes or additional grass seed in late winter when the last few weeks of night-freeze and daytime-thaw aid in seed coverage. Frost seeding works best when legume seed is broadcast on the thinnest, least competitive sod areas. This newsletter date is early March, so the greatest benefits of frost seeding may be behind us.
Interseeding is using a drill to no-till plant legumes or forage grasses into an existing sod. Spring interseeding dates are mid-March through late-April. Grasses are generally more effectively established with interseeding than with frost seeding.
The more traditional perennial grasses, such as smooth Bromegrass, orchardgrass and tall fescue, establish relatively slowly. So if you are interseeding them, don't expect much production contribution early in the growing season.
There is increasing interest in more rapidly-establishing ryegrasses, annual and perennial ryegrass. These are different than grain or cereal rye.
While they establish more quickly, they can exhibit summer dormancy and are short-lived, typically only contributing forage for one or two growing seasons. But they may be an option for a relatively rapid forage contribution to a thin, recovering pasture.
With both frost seeding and interseeding, having the existing pasture sod grazed closely (like what happened with many of our pastures following the summer drought stress) reduces early season sod competition.
Further competition for sunlight and soil moisture by the existing sod can be reduced by timely and thoughtful rotational grazing for the first few months of new seedling establishment.
Evaluate forage resources and inventories - will supplemental forage be needed? Stored forage inventories are at their lowest levels in recent memory. Even average hay yields in 2013 may not be enough to replenish inventories to your desired level or needs.
Consider the extra forage opportunities you may have such as grazing or harvest of fall-planted cereal grain cover crops, and cereal grain companion crops planted with new hay and pasture seedings.
Some producers will likely allocate a portion of their intended row crop acres to the production of summer annual forages, to be used as grazed or harvested supplemental forage. The most commonly used summer annuals are Sudangrass, sorghum-Sudangrass hybrids, and the various grasses classified as "millets" (foxtail millet, Japanese millet, and hybrid pearl millet.)
These crops are generally planted in mid- to late May, and with good weather and management, can provide 1 to 3 harvests or grazings during the growing season.
TheCattleSite News Desk