Updated: Aug 3, 2022
by Chris Teutsch, UKREC at Princeton
Article was originally printed in The Forager a publication of the Virginia Forage and Grassland Council.
A dry summer combined with overgrazing significantly reduces pasture growth and vigor. The good news is that drought stressed pastures often look worse than they really are. This is especially true for pastures that were well managed prior to drought. In many cases pastures can be revived without reseeding. The key element is rainfall and combined with the following suggestions can help to get pastures back into shape.
Rest pastures. In many cases, pastures simply need to be rested. For this reason it is often a better choice to feed hay in late summer and fall rather than grazing recovering pastures. This allows pasture plants to rebuild their photosynthetic factory (leaf canopy) and store up sugars and carbohydrates before the winter months. The growth that accumulates during this recovery period can then be used for grazing during the winter months.
Fertilize pastures. Fertilizing pastures this fall can help to strengthen plants and get them ready to grow next spring. Adjust the soil pH to 6.0 to 6.4, apply phosphorus and potassium according to your soil test, and apply 60-80 lb nitrogen/A in mid-August to mid-September for stockpiling. Alternatively, a smaller amount of nitrogen (40 lb/A) in November or early December can be applied. This late-season nitrogen application will not produce a great deal of fall growth, but it will stimulate tiller production and root growth. Spring growth from these stands will be vigorous and thin areas will thicken faster.
Interseed legumes into thin stands. With increasing nitrogen prices, legumes such as red and white clover, and alfalfa are becoming even more important components of pastures. Pasture sod suppressed by drought and overgrazing provide a perfect opportunity for interseeding clover and alfalfa. Legumes can be either drilled in the fall or spring or frost seeded in late winter. Frost seeding works best with red and white clover and annual lespedeza. Alfalfa is better established using a no-till drill. More information on interseeding pastures is available from your states extension service.
Interseed winter annuals. In some cases, drilling cool-season annuals, such as small gains and annual ryegrass into dormant sods can be cost effective. In this situation sods are normally in very poor condition and there are simply not enough remaining plants to actively compete with the cool-season annuals. However, interseeding cool-season annuals into a dormant sod that was well managed prior to the drought does not work as well as expected in many cases. This is due to the fact that the ground is very dry and when the rain finally comes the seed not only starts to germinate and grow, but so does the dormant sod. An established fescue sod has an extensive root system that competes well for limited moisture. On the other hand, newly established seedlings have a very small root system and are at a serious disadvantage when competing for water with an established fescue sod. The best place for cool-season annuals is on cropland that has already been harvested. In general production on these areas will be greater due to the absence of any significant competition.
It is important to remember that drought alone rarely kills well managed pasture plants. In most cases, drought stressed pastures are in better condition than they appear. Most pastures can be revived with rain, rest, and fertilization. Weakened sods provide a prime opportunity for incorporating legumes in established pastureland. With a little tender loving care and rainfall this year’s drought stressed pastures will be next year’s profit.
Chris Teutsch, UKREC at Princeton