Start Date
2-23-1995 8:40 AM
Description
It has long been recommended that alfalfa fields be rotated to another crop such as com for at least one growing season before reestablishing alfalfa. One reason for doing this is that insect and disease levels build up in the old alfalfa and this time is needed to allow them to die out. Another reason is that alfalfa plants have been shown to produce compounds that inhibit the germination and growth of new alfalfa seedlings. This is called autotoxicity or allelopathy.
Recently researchers from other states have indicated that it may not be necessary to have a full growing season between alfalfa crops. In fact, many are of the opinion that as little as two weeks is long enough after plowing an old stand to reseed a new one, or three weeks for no-till seeding. The reasoning seems to be that the autotoxic compounds will break down in that time and perhaps we are doing a better job of controlling insects and diseases.
We decided to take a new look at how soon we can reestablish alfalfa following alfalfa at the Research Center in Princeton in 1992.
Included in
Establishing Alfalfa Following Alfalfa: How Long Do We Wait?
It has long been recommended that alfalfa fields be rotated to another crop such as com for at least one growing season before reestablishing alfalfa. One reason for doing this is that insect and disease levels build up in the old alfalfa and this time is needed to allow them to die out. Another reason is that alfalfa plants have been shown to produce compounds that inhibit the germination and growth of new alfalfa seedlings. This is called autotoxicity or allelopathy.
Recently researchers from other states have indicated that it may not be necessary to have a full growing season between alfalfa crops. In fact, many are of the opinion that as little as two weeks is long enough after plowing an old stand to reseed a new one, or three weeks for no-till seeding. The reasoning seems to be that the autotoxic compounds will break down in that time and perhaps we are doing a better job of controlling insects and diseases.
We decided to take a new look at how soon we can reestablish alfalfa following alfalfa at the Research Center in Princeton in 1992.