Equine Pasture Renovation and Seeding

If you evaluate an existing pasture and determine that it needs renovation or reestablishment, where should you begin?  Renovating and establishing pastures are an investment of valuable time and money so it pays to plan well and ahead.  As Extension professionals, we address these types of questions regularly.

Any type of pasture renovation project should begin with a thorough evaluation of the area to reseed.  This includes evaluating surface topography, soil fertility levels, soil types, potential compaction issues, existing weed pressures, drainage, and planned pasture uses.  All of these factors help determine the most appropriate techniques for renovation in an individual situation.

Renovation vs. Establishment or Re-Establishment:  When speaking of pasture renovation, we are generally talking about seeding without the complete disruption of the existing sod.  Renovation usually involves one of two methods; broadcast seeding or the use of a no-till drill.  Renovating a pasture without destroying the existing cover is appropriate when a stand has thinned because of severe weather conditions, overgrazing, or age.  Re-establishing a pasture involves some type of tillage equipment and destruction of the existing groundcover.  This is appropriate when establishing a new pasture, when an existing pasture has little or no improved forage species left, when pastures suffer from extreme soil fertility issues or compaction, when severe perennial weed pressures exist, or when drainage issues need to be resolved by moving soil.  Agricultural limestone (used to raise the soil pH, reduce soil acidity, and increase available nutrient levels) moves very slowly through a soil profile at approximately 1 inch per year.  If soil pH values are extremely low, it is often better to spread ag lime and then thoroughly incorporate it into the soil with tillage.  Small pH corrections can be made by topdressing lime.  When you are performing any type of tillage, you must realize that there will be an increased risk of erosion and a need for more time for newly established plants to establish before animals should be allowed back on the pasture.

To evaluate existing fertility levels, you need to have available either a recent (within the last two years) soil test report for that area or take a soil sample for analysis.  Soil testing involves sampling the soil randomly across the pasture and sending a composite, well-mixed sample to a soil test laboratory.  Directions for taking a soil sample are available from the University of Delaware Soil Testing Laboratory (UDSTL) or by visiting their web site at:

http://ag.udel.edu/other_websites/DSTP/index.htm

The ideal way to take a soil sample is to use a soil test probe rather than trying to dig a sample with a spade.  Contact your local county Extension ag agent for assistance in locating soil probes, soil test bags ($10.00 per bag from the UDSTL), and determining  the type of recommendation needed.  Generally, it requires about two weeks from the time a sample is submitted until you receive a recommendation.

Seed germination and vigor can be greatly affected by soil pH and fertility among other factors.  When you consider that renovating a 3 to 4 acre field can cost hundreds of dollars for fertilizer, seed, fuel, and your time; ten dollars is a worthwhile investment!

Soil compaction results from running heavy equipment over wet ground or allowing animals out on wet ground.  Just consider how much weight a horse bears on those four hooves just walking, let alone the force of a cantering or galloping hoof making contact with wet ground.  We once visited a farm in Sussex county where high stocking rates and years of horses being out on wet ground had combined to create enough soil compaction that it was having an adverse effect on the forage plant growth and survival.  Keeping animals off of wet pastures can positively affect the longevity and health of your forage stands.

In extreme cases of perennial weed infestation in pastures, the use of a systemic herbicide followed by complete renovation may be in order.  A well established, healthy and productive forage stand helps to ward off weed infestations.  Weeds are opportunists.  They tend to establish in bare spots in a forage stand.  Spreading manure containing waste hay (and weed seeds) on pastures often introduces weed problems.  Many weed issues can be solved by simply mowing you pasture regularly and maintaining a healthy soil pH and adequate nutrient levels that encourage forage growth.

Evaluating pasture areas for drainage issues is important.  Standing water has multiple negative effects.  It certainly has a negative effect on forage stands, soil compaction, and even horse health.  Wetter areas may have special seeding needs.  Some pastures species tolerate “wet feet” better than others.  Generally speaking, pasture areas should be firm and level.

There are a number of questions you should ask yourself about the intended use of your pasture.  Be realistic with your answers.  These questions include:  What type of animals am I going to be grazing?  How much acreage do I have per animal?  What stocking density am I going to carry on that land?  Am I going to use the pasture as a nutrition source or simply as an exercise lot?  Do I have the ability to rotationally graze [moving animals among paddocks (a fenced area of pasture) based on forage availability] or will I be grazing continuously (one field with animals always on it)?  Do I plan on doing any breeding either now or in the future?  How much time do I have to spend on managing my pastures?  What kind of access do I have to equipment?  The answers to these questions must be factored into regional considerations as well as your site specific factors when we recommend pasture forage species.

Forage species each have their own individual characteristics and therefore may be better suited to one person’s operation than another.  I am going to discuss a few of the common pasture forage species used in Delaware and their main characteristics.  This is by no means an all encompassing list.

Kentucky bluegrass-   Kentucky bluegrass is a great choice if it works in your region of the state.  Unfortunately, Kentucky bluegrass is only suited for conditions in the northern portion of New Castle County.  It prefers heavier, denser soils that are not typically found in Kent and Sussex Counties.  Bluegrass forms a dense sod so it tolerates hoof traffic well and is long-lived.  It is a cool-season grass that goes semi-dormant during hot, dry periods in the summer.  Cooler and wetter fall conditions stimulate regrowth of the grass. This species is slow to establish (it can take 28 or more days for the seed to germinate) but it is highly palatable to horses.

Perennial ryegrass- Do not use the turf-type perennial ryegrasses (these varieties are bred to contain an endophytic fungus that produces toxins beneficial to the plant’s survival but not to animal performance/health).  Consider using a tetraploid type of perennial ryegrass since these varieties are bred to yield better and to have more disease resistance.  Perennial ryegrass is a cool-season grass that does best on fertile, well-drained ground.  It does tolerate wet soils better than some of the other cool-season grasses.  It is very rapid to establish, highly palatable, and highly digestible.  However, it will not persist in a pasture for more than a couple of years.  It does best when seeded with a legume; otherwise, it needs regular applications of nitrogen (N) fertilizer.

Timothy- Timothy is generally not used for grazing.  If grazed, it must be rotationally grazed.  It does not tolerate set, season-long grazing.  It does tolerate slightly wet, heavier soils but does not tolerate drought because of its shallow root system.  It is a bit finicky about seeding depth, being very small seeded.  It is not a very competitive plant so other grasses can out compete it.   It is one of the few grasses that performs better when spring seeded.  Timothy is commonly found in pasture mixtures probably because it has a reputation as a feed horses favor and not because it contributes to long-term pasture productivity.

Orchardgrass- Orchardgrass performs best under rotationally grazed systems.  It does not tolerate overgrazing well or lots of hoof traffic.  It needs well-drained fertile soils.  It does tolerate drought, heat and shade better than timothy, Kentucky bluegrass and perennial ryegrass.  It is a bunch grass and does not form a dense sod.  It performs best when mixed with legumes such as ladino clover or red clover.  If not seeded with a legume, it needs regular applications of N fertilizer.

Tall fescue- Again as with perennial ryegrass, avoid using anything called turf-type tall fescue since these varieties are bred to contain high levels of an endophytic fungus.  Tall fescue is known as the “Queen of Wear and Tear.”  It has the ability to form a sod and resist trampling in wet weather.  It stays green longer into the winter season than other cool-season grasses and survives drought better than many other forage species.  It also tolerates “wet feet” better than some other forage species.  It is not the best choice for those breeding horses because of the toxic effect of an endophytic fungus that lives within the plant.

 

Endophyte-Free Tall Fescue- Endophyte-free fescue is sold under several trade names.  It is essentially the tall fescue with the endophytic fungus removed.  However, those characteristics of toughness and persistence that make Kentucky 31 tall fescue so great are largely lost once the endophytic fungus is removed.  Longevity in a forage stand, tolerance to grazing and hoof traffic, and drought tolerance are reduced with endophyte-free tall fescue varieties.

Novel Endophyte Tall Fescue- Novel endophyte fescue is sold under the trade name Max Q fescue.  Novel endophyte fescue has been modified in such a way that the endophyte fungus is left in the plant but does not produce toxic compounds.  Because of the technology used to develop this plant, the seed commands a much higher price.   It maintains many of the good characteristics and toughness of Kentucky 31 tall fescue without the associated animal reproductive problems.  It seems to do best when established through conventional tillage methods and is a bit slower to establish.  Graze lightly and carefully at first and allow plenty of time for the grass to establish.

Ladino clover- Ladino clover is a large type of white clover.  Clovers are also legumes that can fix their own N from atmospheric N and share some of it with nearby grasses reducing the need for fertilizer N.  It is commonly used in mixed grass legume pastures.  It is cold tolerant but has low tolerance to heat or drought.  Ladino clover tolerates grazing to a 2 inch residue height.  It can be easily added to an existing pasture by frost crack seeding.  Frost crack seeding is the process of broadcasting seed in late winter when the ground is repeatedly freezing and thawing.  This action helps work the clover seed into contact with the soil.  Although in most cases it does not need a bacterial inoculant added to the seed, it is prudent to apply the appropriate inoculant to the seed before planting.  Ladino clover seed is very small so you get more seeds per pound than with many other forage crops.  Seed at 1/2 lb. per acre or less, otherwise your pasture can become overwhelmed with clover.

Red Clover– Red Clover is best used under rotational grazing and can also be cut for hay.  It does not tolerate continuous close grazing.  It does tolerate lower pH better than some other legumes  Red clover is a short-lived perennial but does produce seed even when grazed so it reseeds itself easily.  Some people are hesitant to use red clover in horse pastures because occasionally it may cause a horse to get slobbers.  This is not a result of the red clover itself but rather a chemical produced by a disease that sometimes affects red clover called black patch.  A case of the slobbers is more of a nuisance than a health concern

As I said before, this is by no means a complete list of available forages but these are the main ones in use in our area.  A quick note about clovers: Alsike clover does occasionally cause problems for horses and is part of the reason we do not recommend using an off-the-shelf pasture mix from your local farm supply store.  These premixes often contain alsike clover since it can tolerate wet soil conditions.  Another reason not to use these pasture mixes is that they generally contain species that are not appropriate for your area.  If you want to plant a mix, consider making your own mix by combining seed of 1 or 2 grasses plus a legume.  Many seed dealers have seed blenders and will gladly mix your purchased seed.  Another option is to plant the grass seed in the fall and allow the grass to establish.  The next spring or even several springs later a legume can be frost crack seeded.

Unless otherwise noted above, plant cool-season grasses in late summer or early fall.  The calendar should not be the only deciding factor.  Soil moisture needs to be sufficient at planting.  If the seeding does not have enough time to get established before winter, winter kill is a possible.  Late seeding can delay when you can start grazing animals on the pasture as well.   Successful spring seeding of grasses is difficult to accomplish due to delays in seedbed preparation in wet springs, weed competition, and the risk of early-season heat and drought when seedlings are most susceptible to stress. 

For pasture renovations without sod destruction, it is necessary to mow or graze the existing forage close to help reduce competition from existing plants.  The use of a no-till drill or broadcasting seed are the most common establishment methods in pasture renovations.  Many county conservation districts have no-till drills that can be rented.  You will need to make sure you have a tractor that has the necessary horsepower to handle the no-till drill and you will need to call ahead to reserve the drill.  It is important when using a no-till drill to check your seeding depth since some species are very sensitive to seeding too deep.  When broadcasting seed over an existing pasture, it is important to ensure sufficient soil to seed contact.  Personally, we have found we have better results when we drag the pasture fairly aggressively prior to broadcasting the seed and then drag less aggressively after seeding rather than broadcasting the seed without any soil preparation.  Use higher seeding rates when broadcasting seed versus using a no-till drill since seed can be lost to wind, rain, and pests.  When seeding a pasture after conventional tillage, it is important to have a level, firm weed-free seedbed prepared prior to seeding.

In general whether you are planting a new pasture or renovating an existing one, more is better.  Logically, more seed results in more plants.  However, more time, more planning, more knowledge, more information and more careful management will result in more pasture for more years.