Oats is often planted as a nurse crop or carrier with perennial crops such as clover or alfalfa. In that way a farmer will get a crop of oats the first year and the perennial will come in the following years.

They are just applying the technique here. Keep in mind that the oats is annual and the chicory or cloverare perennial.

Chicory, clover and alfalfa are best planted in the spring to take advantage of spring soil moistures. They can also be fall planted as a dormant or frost seeding.

Brassicas can also be planted in the spring but can be an issue as the plant may be to a flower stage prior to the first killing frost...which could result in a stemmy, unpalatable plant with low protein. Deer have been know to still go after Brassicas even at that stage however.

The technique to plant Brassicas later is to allow the first killing frost to stop the growth just at the right time...no mowing to cut it back would be needed and the plant doesn't get to stemmy.

I hope this helps clarify. This link will give you some additional information as well...

http://www.habitatnow.com/store/shop/shop.php?pn_selected_category=10

Good luck!

Land DR