Tips for spring forage seeding
With the wet spring weather the past couple of years, many farmers have had problems getting spring-seeded forages established. Some of the resulting stands of alfalfa, for example, aren’t very good.
Ground was worked wet, creating a cloddy seedbed resulting in poor seed-to-soil contact. In some cases, seedling diseases took a toll due to cool, wet weather. It was so wet in some areas that planting of forages, whether alfalfa or grass, or a legume-grass mix, was so late that stands were disappointing for that reason, too.
• Forage seedings can be made in spring as soon as suitable seedbed is prepared.
• Seedings made after mid-May may not be as successful, due to rapid drying of soil.
• On sloping sites consider the need for a cover crop for soil erosion protection.
“Forage seedings can be made in the spring as soon as a suitable seedbed can be prepared,” says Steve Barnhart, Iowa State University Extension forage agronomist. “Spring seedings made after mid-May may not be as successful, due to rapid drying of surface soils.” As much as you have to pay for seed and the cost of getting it into the ground, you should try to do the job the right way. Barnhart offers the following recommendations:
• Site preparation. If you are seeding a pasture, clear the brush, fill in gullies and take soil samples. Lime and fertilize according to needs shown by soil testing. For most efficient lime use, it’s best to have needed lime applied and incorporated six months to a year before planting.
• Seedbed preparation. Destroy sod by shallow plowing or disking, followed by necessary secondary seedbed preparation. Seedbed firmness is very important. Using a cultipacker or roller on tilled seedbeds before planting is recommended. An alternative is to use a nonselective herbicide to kill the old sod. Incorporate fertilizer before seedbed preparation, or surface top-dress it on killed sod.
• Species and variety selection. Select species based on the desired use, persistence and tolerance to site conditions. ISU Extension publication “Selecting Forage Species,” PM 1792, covers characteristics of many forage legumes and grasses in Iowa, and offers suggested seeding mixtures and seeding rates for various situations.
• Seeding. Seed in one of the following ways on a well-prepared seedbed:
Use a grassland drill with depth-control and press wheels, or a cultipacker-roller type seeder for small-seeded forage legumes and grasses. Plant ¼ to ¾ inch deep.
Use a grain drill with small-seeded forage boxes as a broadcast seeder for small-seeded legumes and grasses to prevent small forage seed from being planted too deeply. Cultipack or roll after seeding.
Broadcast seed onto a firm, tilled seedbed and cultipack or roll for shallow seed coverage and seed-to-soil contact.
If planting into a killed sod or untilled crop residue field, use a no-till drill, control seeding depth within a ½ inch, and adjust press wheels for good seed-to-soil contact.
Be careful on slopes
On sloping sites consider erosion protection. Where there is a risk for erosion on tilled seedbeds, 1 to 2 bushels of oats per acre or a reduced seeding rate of another spring cereal grain may be seeded with forage mixtures as a companion crop or cover crop. The cereal grain will serve first as soil erosion protection, but will increasingly become competition for the newly planted forages. The sooner the cereal competition can be removed, the quicker the new forage seeding will establish.
Cereal companion crops may be grazed, cut for silage or hay, or harvested later as grain and straw with associated longer completion. Particularly in dry springs, removing companion crops as early as possible can save moisture for the new forage.
For weed control and for companion crop competition control, graze new seedings rotationally or mow (clip) sequentially, during the first few months of the establishment to limit unneeded competition for light, moisture and plant nutrients. The developing seedlings will establish more quickly. Also, avoid any cutting or grazing of new seedings after early September to improve winter hardening.
For some mixtures or pure stands, selective preplant or postemergence herbicides may be used in place of a companion crop. This option may only be appropriate on sites where erosion is not a risk. Seek help from your ag professionals when selecting and using herbicide for weed management in new forage seedings. Be sure to read and follow labels when using any ag chemical. Also, take into account any harvest or grazing withdrawal periods needed. You can apply fertilizer in later years according to soil test recommendations.
Graze rotationally and avoid overgrazing to maintain ground cover and animal gains. Remove grazing livestock and limit grazing for the last four to six weeks of the growing season to allow plants to adequately harden for winter. Use management practices that retain adequate plant cover if cutting or grazing after fall dormancy.
Source: ISU Extension
This article published in the April, 2011 edition of WALLACES FARMER.