|Ohio Farm News
By Steve Bartels
Now that we are past March 15, we can seed forages just as soon as the soils will allow. The key to success for forage seeding is prior planning. A soil sample is required before you seed.
If the levels of phosphorus or lime are low and you are not tilling the soil, the needed fertilizer and lime should have been put on 12 months ago. If you are going to till the fertilizer and lime into the soil, putting the corrective amounts on six months in advance is adequate.
So what do I mean by corrective amounts of materials? If the soil test recommends any lime, that is corrective. If you need to apply phosphorus or potassium at replacement levels, that is not corrective. If levels in the soil are only going to be maintained, applying replacement fertilizer at the time of seeding should be adequate.
So if you need lime or corrective phosphorus or potassium, change your plans to seed. The investment is too big to get a forage stand established to have it fail because of lack of nutrients. Move your seeding date back six months to a year.
We never recommend seeding alfalfa into a field that has an old stand of alfalfa in it. Alfalfa releases a chemical that reduces the germination and growth of new alfalfa plants. This is called autotoxicity. This toxin leaches slowly from clay-based soil. There are also a number of disease pathogens in that old stand that are just waiting to jump on the new seedling. Use a field that has not had forage in it for at least one year. Make sure the herbicides used on last year’s crops will not interfere with stand establishment.
Use a high quality seed, free of weed seed and with a high germination rate. You can go online at http://forages.osu.edu to get information from the performance trials for Ohio and adjoining states.
Inoculate legume seed with the proper nitrogen-fixing bacteria to assure good nitrogen fixation. Make sure the inoculant was stored in a cool dry place before you use it.
The weather for the week prior to March 15 was pretty wet. As soon as the soil is dry enough to prepare a proper seedbed, seed! You should be done by late April. The forage needs time to “harden off” before we have hot, dry weather. It should germinate 60 days or more before July 1.
This farm news was published in the March 22, 2006 issue of Farm World.