By Mark Sulc, Jason Hartschuh, CCA, Ohio State University Extension
Early spring provides one of the two preferred times to seed perennial cool-season forages, the other being late summer. Given our current weather patterns, planting opportunities will likely be few and short again this spring, continuing the pattern of the past several years. So we need to be ready to roll when the weather gives us a planting window. The following 10 steps will improve your chances for successful perennial forage establishment.
- Check now to make sure soil pH and fertility are in the recommended ranges. Follow the Tri-state Soil Fertility Recommendations (https://forages.osu.edu/forage-management/soil-fertility-forages). Forages are more productive where soil pH is above 6.0, but for alfalfa it should be 6.5 to 6.8. Soil phosphorus should be at least 20 ppm for grasses and 30 ppm for legumes, while minimum soil potassium should be 100 ppm for sandy soils less than 5 CEC or 120 ppm on all other soils. If these soil test levels are not present, or you don’t even have a recent soil test, we recommend making corrective lime and fertilizer applications this spring and seeding an short season forage for the summer and delay establishing the perennial forage stand until late summer.
- Plant high quality seed of known varietal source adapted to our region. Planting “common” seed (variety not stated) usually proves to be a very poor investment over the life of the stand. Forage yields from “common” seed are often less even in the first or second year and have shorter stand life.
- Calibrate forage seeders ahead of time. Seed flow can vary greatly for different varieties and depending on the seed treatment and coatings applied. For example, many new alfalfa varieties are sold with a 34% clay coating by weight, so your actual pure live seed rate would be dramatically reduced if you don’t adjust for the seed coating. We recommend watching the video entitled “Drill Calibration” available at https://forages.osu.edu/video/.
- Prepare a good seedbed as soon as soils are fit. The ideal seedbed for conventional seedings is smooth, firm, and weed-free. Don’t overwork the soil. Too much tillage increases the risk of surface crusting. Firm the seedbed before seeding to ensure good seed-soil contact and reduce the rate of drying in the seed zone. Cultipackers and cultimulchers are excellent implements for firming the soil. If residue cover is more than 35% use a no-till drill. No-till seeding is an excellent choice where soil erosion is a hazard. No-till forage seedings are most successful on silt loam soils with good drainage and are more difficult on clay soils or poorly drained soils. You will want no-till fields to be smooth because you do not want to bounce over them for all the years of this stand.
- Look for opportunities to seed as soon as possible now. Earlier planting helps forage seedlings get the jump on weeds and the forages establish before summer stress sets in. Weed pressure increases as planting is delayed, and forages will not have as strong a root system developed by early summer when conditions can turn dry and hot. Later plantings also yield less. Given the current conditions, we expect planting won’t be possible until sometime in May in many parts of the state. If planting gets delayed past mid-May, it might be better to plant a summer annual and establish the perennial forages in August.
- Plant seed shallow (.25- to .5-inch deep) in good contact with the soil. Stop and check the actual depth of the seed in the field when you first start planting. This is especially important with no-till drills. In our experience, finding some seed on the surface indicates most of the seed is at the right depth.
- When seeding into a tilled seedbed, drills with press wheels are the best choice. When seeding without press wheels or if broadcasting seed, use a cultipacker before and after broadcasting the seed, preferably in the same direction that the seeder was driven.
- In fields with little erosion hazard, direct seedings without a companion crop in the spring allows harvesting two or three crops of high-quality forage in the seeding year, particularly when seeding alfalfa and red clover. For conventional seedings on erosion prone fields, a small grain companion crop can reduce the erosion hazard and will also help compete with weeds. Companion crops like oat can also help on soils prone to surface crusting. Companion crops usually increase total forage tonnage in the seeding year, but forage quality will be lower than direct seeded legumes. Take the following precautions to avoid excessive competition of the companion crop with forage seedlings: (i) use early-maturing, short, and stiff-strawed small grain varieties, (ii) plant small grains at 1.5 to 2.0 bushels per acre, (iii) remove companion crop as haylage or early pasture (only if soils are firm), and (iv) do not apply additional nitrogen to the companion crop.
- During the first 6 to 8 weeks after seeding, scout new seedings weekly for any developing weed or insect problems. Weed competition during the first six weeks is most damaging to stand establishment. Potato leafhopper damage on legumes is especially of concern beginning in late May and continuing most of the summer.
- The first harvest of the new seeding should generally be delayed until early flower stage of legumes (approximately 60 days after emergence) unless weeds were not controlled adequately and are threatening to smother the stand. For pure grass seedings, generally harvest after 70 days from planting, unless weeds are encroaching in which case the stand should be clipped earlier to avoid weed seed production.