Fall Management Tips For Drought-Stressed Forages

Summer drought in 2012 has led to tight hay supplies and high prices. Consider these forage management tips as you prioritize your options.

Published on: Oct 4, 2012

The Midwest has seen some of the most extreme drought conditions of recent memory. Some rain has come recently for most of this area, but not enough for most people, especially farmers, to feel comfortable. Many pastures remain in poor condition. Many hayfields are showing enough recovery to maybe yield at least one more cutting. Regionally, hay supplies are tight and prices are high.

Forage management considerations are many. Here are some things to think about as you prioritize your options for 2013. Iowa State University Extension forage agronomist Steve Barnhart offers the following news, views and observations.

HAY IS VALUABLE: Hay is in short supply and is high priced. While many pastures are still in poor condition from summer drought, hayfields are showing some recovery. Forage management options are important to consider as you plan for 2013.
HAY IS VALUABLE: Hay is in short supply and is high priced. While many pastures are still in poor condition from summer drought, hayfields are showing some recovery. Forage management options are important to consider as you plan for 2013.

Pity those poor hayfields and pastures after the major drought of 2012

The goal is to help keep perennial forage plants 'perennial.' During the fall weeks, perennial forage legumes and grasses respond to shortening days and cooling average daily temperatures and progress through their gradual "cold hardening" process. The genetics of the forage variety and the local climatic conditions determine how cold tolerant the plant crown and taproot can be during the winter months.

Most successfully winter-hardened perennial forage legumes and grasses can withstand soil temperatures in the crown area to about 0 to 4 degrees F without crown tissue damage. At lower soil and crown temperatures, varieties and individual plants will vary in the degree of cold damage they may experience.

To best acquire their potential for winter survival, these forage plants should get five to six weeks of uninterrupted growth to accumulate root carbohydrates and proteins before going dormant for the winter. A 'killing freeze' is about 23 to 24 degrees F for several hours. After that occurs, no more cutting or grazing until next season.

If you decide to make a fall cutting or graze the forage, you must manage it

If you do decide to cut one more hay cutting or grazing in the fall, it is important to manage fall harvests or grazing to give the forage plants the best chance for strong winter survival. It is best to wait until at or after the killing freeze (23 to 24 degrees F) for the last hay cutting, then leave a 5-inch to 6-inch stubble. It is not recommended to take a late season harvest from a new (that is, 2012) seeding.

The same goes for late season growth management of pastures. Try to allow three to four weeks of fall recovery before a killing freeze, and then, if you are going to graze again, leave an average of 3 inches or so of lower stem bases on the grasses. The practical problem with these management strategies is that it involves removing livestock from pasture. And no more hay harvest -- in an already hay shortage season. Each individual has to make those decisions about their fields, based on what is most important for their situation.

Fall is good time to pull soil samples, have them tested, fertilize if needed

Fall is a good time to soil test and fertilize both hay and pastures with needed potassium (K) and phosphorus (P). This will help drought-stressed forage stands to overwinter and improve regrow and yields next spring. Applying 25 pounds to 40 pounds of nitrogen to grass pastures during the last few weeks of their fall growth will aid in stimulating more fall tillering or branching and promoting a more vigorous recovery in the spring.

Give recovering hay and pasture stands time to 'catch up' or regain more vigor next spring. If fall recovery was not favorable, or you did cut or graze 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 next 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.

Repairing and reseeding these drought-thinned pastures this coming year

Consider 'interseeding' or 'frostseeding' drought-thinned pastures this coming year, do it in late winter or early spring of 2013.

* Frostseeding is the broadcasting of legumes or additional grass seed in late winter when the last few weeks of night-freeze and daytime-thaw aids in seed coverage.

* Interseeding is using a drill to no-till legumes or forage grasses into an existing sod. Spring interseeding dates are mid-March through late-April.

Frostseeding works best with legumes on the thinnest, least competitive sod areas. Grasses are generally more effectively established with interseeding than with frostseeding. With both frostseeding and interseeding, having the existing pasture sod grazed closely (like many of our pastures following the summer 2012 drought stresses) reduces early season competition between established forage and the new seedlings.

Further competition for shade, sunlight and soil moisture can be reduced by timely and thoughtful rotational grazing for the first few months of new seedling establishment. For more details, read these ISU Extension publications: Pm-856, Improving Pasture by Frost Seeding, and Pm-1097, Interseeding and No-till Pasture Renovation.