Part 2- What Should I Plant?

Now that you’ve taken care of any soil fertility issues that can reduce the chance for a successful stand, the next decision involves choosing the right seed to plant.  I’ve had the opportunity over the years to read many seed labels on various pasture mixes offered for sale.  I understand the convenience of buying a prepared pasture mix and the allure of these mixes.  The buyer often assumes that the seller has spent the time and energy studying the issue and has come up with a mixture that in their opinion and experience has the best chance of success.  I certainly can’t speak to motivation of the seller but keep in mind that from a business point of view, seed that is mixed and offered for sale needs to be sold over as large an area as possible to justify the expense of wholesaling large quantities of seed as well as blending, packaging, and labeling the seed.  In my opinion, this nullifies the expectation that the seller has designed the mix for your particular field or location.

After looking at the species of forages used in the prepared pasture mixes, I find that these mixes are more often a shotgun approach to seeding.  A bit of everything is included in hopes that something will establish in all areas of the field.  Usually they contain a quick establishing grass such as annual or perennial ryegrass that can germinate in as little as 5 to 7 days so the buyer can feel comfortable that the new seeding is successful.  Horse pasture mixes usually contain the feel-good or highly recognized grasses such as timothy and Kentucky bluegrass along with some orchardgrass and probably an endophyte-free tall fescue to provide more permanent cover.  Finally, a legume such as white or ladino clover, red clover, or alsike clover will be in a pasture mix to provide the N-fixing legume everyone wants in a pasture.

The convenience of these mixtures comes from not having to mix them yourself before you fill the seed drill.  The allure comes from not having to make a decision other than how much seed per acre to plant and not having to choose individual species to plant.  For most buyers, the convenience and allure end up costing them many, many dollars per acre in seed costs for seed of grasses that won’t survive in grazing situations or won’t survive more than a season or two at best or will be unproductive during the middle of the summer grazing season.

Tall Fescue photo provided courtesy of Oregon State University

So what should you do?  I prefer going with a simpler mixture using forage species that are adapted to our region.  In most cases, the only species that will survive for many years in our transitional zone climate is tall fescue.  Because of endophyte (an fungus growing in some tall fescue plants) issues, many growers have tried the endophyte-free tall fescue varieties and some have had success with keeping a stand for many years while others have seed stands decline or disappear quickly.  The newest chapter in this issue has been the development of novel or friendly endophyte tall fescue varieties.  The novel endophyte tall fescue varieties do not produce the chemical compound (alkaloids) that interfere with animal performance but still provide benefits to the tall fescue plants helping them survive in many stressful environments.  A limitation still in evidence with these new tall fescue varieties is that horse owners who breed horses do not all accept tall fescue as a feed source for their animals.  This can limit tall fescue’s acceptance.

What other species can you include in your simple mixture?  Orchardgrass is another grass that many producers like to include in a pasture mixture but you should be aware that many orchardgrass fields are failing due to a disease/insect/environment/management complex interaction we’ve been calling orchardgrass decline.  If you choose to include orchardgrass, keep it as a small

Orchardgrass photo provided courtesy of University of Missouri Exetension

proportion of your mixture.  The other grass to include at least on heavier soils and in the northern portion of Delaware is Kentucky bluegrass.  Be sure to include several varieties of the Kentucky bluegrass to help with disease resistance.  It will be most productive early in the year (early spring to early summer) and mid- to late-fall.  Finally, add in a legume to help with providing N for the grass to use as well as to improve the protein and forage digestibility of the pasture.  For grazing, most people prefer a ladino-type of white clover.  Although slobbers (the animal produces excessive amounts of saliva) is a potential concern with all clovers, it seems to be mostly associated with red clover.  Often included in commercially sold horse pasture mixtures, alsike clover is known to cause photosensitivity (sunburn) and sometimes liver injury especially in horses and should not be included in your pasture mix.

One of the new grazing-types of alfalfa should be considered especially by beef producers.  These varieties tolerate rotational grazing systems and produce well during the summer period in most years.  Alfalfa is very deep rooted and can be a great addition to pastures and provide more and higher quality forage in the summer grazing period.

You will find it useful to talk to your seed dealer about the various varieties of each species that are available.  Once you decide on the varieties to use and you purchase seed, you can mix your own pasture mix by either purchasing or renting a cement mixer and combining the seed in the proportions you decide are best for your purpose and field.  Since many legumes now come pre-inoculated with the N-fixing bacteria and often are coated with a fine limestone, do not over mix the seed and when you re-bag it store it where it is protected from high temperatures and humidity.  Stored properly, the seed can be held over the winter if something prevents you from seeding this fall but you should plan to plant as soon as possible after purchasing seed.  Not only are the N-fixing bacteria alive; but, if you use a novel endophyte tall fescue variety, the endophyte has a limited storage time (around a year under good conditions) before it needs to be planted.  Although tall fescue seed will germinate after longer storage times, the endophyte fungus may no longer be alive.  The fungus only lives in the plant and is not soil-borne.

In future articles later this summer, I will cover topics such as planting date.

This article was submitted by Dr. Richard Taylor, Extension Agronomist, University of Delaware.  Dr. Taylor can be reached at rtaylor@udel.edu