Fallow ground in WI

I have 13 acres that did not get plowed and planted to a cash crop this year due to wet field conditions and a new job. My first thought was to try fall seeding alfalfa, but now I'm thinking a cover crop may be a better option. It's been nice to have place to spread manure but would rather see something growing in there. The field was corn last season (2016) and likely go back to corn again next season (2018). What cover crop/crop mix would you guys recommend?

Alfalfa only if you plan on making hay for a few years. As far as a tempory cover crop I have no idea.

Some grow field radish, and Buckwheat will cover the ground , and prevent weed growth.

Most seed companies offer a plow down alfalfa. It is the objective of the landowner in the end. There are cheaper options but remember that alfalfa is a legume that can build nitrogen into the soil. I would seed as soon as the field was prepared and rain was in the forecast.

Alfalfa will not do well in wet ground.

I would plant a cover crop.

Alfalfa seed is darned expensive. Rye grows up quick. Radishes and tillage turnips will help loosen the soil and fix a small amount of nitrogen.

Rye is cheap and a fast grower. You need to get it cut quick in the spring or it can get away from you. Also are your going to plow it down or spray it/plant? It all makes a difference. Alfalfa is a expensive crop to seed down. So it would more for year of hay in the future.

Some thing I have done that works well is to seed spring Oats and clover now. The oats will grow pretty fast but will winter kill. The clover will fix nitrogen and hold it for the next crop. I just used clean feed oats not seed oats for cover crop. You would not need certified oats for a cover crop.

Whatever you seed make sure it is clean from weed seeds. Guys around here got grass seed out of the Texas and Oklahoma last year for CRP an the majority of it had weed seeds in it. The worst being Palmer amaranth. In tested seed samples it was found in just about all of them even thought they were labeled weed free. So much of the CRP seeded down last year has had to be sprayed repeatedly this year to try and control Palmer amaranth. The CRP ground that has not been sprayed is looking bad and that will make a seed bank to spread all over.

Granted that there are cheaper alternatives for a cover crop but alfalfa for plow down should not be prohibitively expensive. Around here there are off the combine alternatives for legume and grass seed as long as you are not looking for patented features. The OP did say that the ground was going into corn for 2018 so alfalfa only needs to last until winter and if the winter is not too harsh and wet then the alfalfa most likely will be there for a spring plow down if the OP so chooses. Clover is a decent alternative but it seems like alfalfa has the edge in getting a start in terms of a new seeding this time of year. If the OP was looking for a long term stand on alfalfa then he would need to address drainage, PH, and fertility.

Been years since I was making hay. At that time there was no plow down alfalfa. The cheapest twas considered a 2 hay year crop and last I heard it was more expencive to put in a crop of alfalfa than a crop of corn.

Yes, alfalfa will be expensive IF you are gearing up for a multi-year stand for hay production. If you are going to turn it under during the fall or the next spring then you have the cost of seeding, tillage if not no-till, and a small amount of fertilizer. Companies have what they call plow down alfalfa which lacks traits for combating insects and so forth. Good enough just to take up space until fall and produce some nitrogen. I don't do much with hay unfortunately but it has been a long time since I needed to buy big brand alfalfa, red clover, or timothy seed because many guys will combine some acreage for seed. I have never had a problem with germination or foreign material in the seed. The one time I bought some iffy timothy seed the producer let me know he tested the germ at around 85 percent and that is what I observed. With clover the old timers used to say seed before May 15 or after August 15. They claimed the seedling lacked vigor if it got hot after it broke the soil crust. Some soils here are heavy to the point where they are the best legume for a long term stand. Back when a lot of wheat was raised it was normal to get clover as a volunteer crop as the wheat was getting ready for harvest. I kind of miss raising wheat for that reason.

I'd plant the cheapest medium red clover you can find, and do it immediately, if the field is close to dry enough. Clover will be cheaper than alfalfa, and if you get good growth this fall ( i've seen it get waist high in WI) you can credit 50 to 80 lb of N for next years corn crop. 50 lb would be a safe number if the stuff is knee high by freeze time. That will more than cover your seed cost, and I think you will see a yield bump in the corn as well.

If the stuff gets up and growing well, you may be able to do some LIGHT manure application out there, too.

Clover and alfalfa both have root systems that were compaction breakers long before today's "tillage radish".