Forage Focus: New Forage Seedings, The Window Of Opportunity Is Upon Us

By Stan Smith

With the weather allowing so few new forage seedings to be established in Ohio the past couple of springs it would appear this August might offer a window of opportunity. With adequate sub-soil moisture levels presently across much of the state, a couple of timely showers will insure emergence that will allow new seedings the 6 to 8 weeks of growth required before dormancy.

If it's not already been accomplished, soil samples should be pulled immediately in order that corrective lime and fertilizer applications may be made in a timely fashion. Now, before seeding, is also the time to eliminate any perennial weeds as well as the annuals that have emerged.

OSU Extension Forage Specialist Mark Sulc offers the following 10 highlights of key management steps toward successful establishment of forages in August.

1. Apply lime and fertilizer according to a soil test. Since the stand will be used for several years, ideally the soil test should have been taken within the past year.

2. Control problem perennial weeds ahead of seeding. Be careful with herbicide selection because some have residual soil activity and will harm new forage seedings if proper waiting periods are not observed. Be sure to read the labels of any herbicides being considered.

3. Plant new perennial forage stands as soon as possible in August. Seedlings require at least 6 to 8 weeks of growth after emergence to have adequate vigor for winter survival. In northern Ohio, plant during the first two weeks of August. In southern Ohio, plant by August 30. Later planting may work, but there is greater risk for failure and the stand may have lower yield potential next year. The new stand should have six to eight inches of growth before a killing frost. Slow establishing species should be planted as early as possible. Fast establishing species like red clover, alfalfa, and orchardgrass can be seeded up to the dates listed above if moisture is present. Kentucky bluegrass and timothy can actually be seeded 15 days later than the dates listed above.

4. It is risky to place seeds into dry soil - there may be just enough moisture to germinate the seed but not enough to get the seeding established. Either plant soon after a rain when soil moisture is adequate, or when a good rain system is in the forecast.

5a. No-till seedings conserve moisture and can be very successful provided weeds are controlled prior to seeding. Using no-till when herbicide-resistant weeds are present creates a very difficult situation with no effective control options, so tillage is probably a better choice in those situations. Where such weeds are not an issue, remove all straw from fields previously planted to small grains. Any remaining stubble should either be left standing, or clipped and removed. Do not leave clipped stubble in fields because it will form a dense mat that prevents good emergence.

5b. If you are going to use tillage, don't over-till and be sure to prepare a firm seedbed. Loose seedbeds dry out very quickly. Deep tillage is not ideal for late summer seedings. A cultipacker or cultimulcher is an excellent last-pass tillage tool. The soil should be firm enough that the your boot leaves a print no deeper than 3/8 inch (you can bounce a basketball on it).

6. Plant the seed shallow (1/4 to 1/2 inch deep) and in firm contact with the soil. Carefully check seeding depth, especially when using a no-till drill. A drill with press wheels provides the greatest success with summer seeding. Broadcasting seed on the surface without good soil coverage and without firm packing is usually a recipe for failure in the summer.

7. Use high quality seed of known forage-type varieties from reputable dealers. Cheap seed often results in lower yield and shorter stand life. Check out our variety performance trials and those of neighboring states.

8. Make sure legume seed has fresh inoculum of the proper rhizobium to ensure nitrogen fixation. If the seed is pre-inoculated, check with the seed supplier to ensure the seed was stored under conditions that guarantees viable inoculant.

9. If planting alfalfa, don't plant new alfalfa immediately after an older established alfalfa stand. Autotoxic compounds are released by old alfalfa plants, which inhibit growth and productivity of new alfalfa seedlings. You can seed in alfalfa in late summer to thicken up a new alfalfa seeding that was made this spring. The autotoxic compounds are not present in young alfalfa plants. They are released from older, established alfalfa plants.

10. As the stand develops this fall, do not be tempted to harvest it. No matter how much growth accumulates, it is usually best to let the cover protect the new crowns during the winter. The only exception to the no fall harvest rule for late summer seedings is perennial ryegrass. If perennial ryegrass has tillered and has more than six inches of growth in late fall, clip it back to 3 to 4 inches in November or early December. Finally, scout new seedings for winter annual weeds in October. Apply herbicides as needed. Winter annual weeds are much easier to control in late fall than they will be next spring.

Source:osu.edu