If your only planting a narrow strip around the edge (20 ft?) I'd skip corn, for MANY reasons. Corn grows best when planted in blocks so it can cross fertilize, long narrow strips of corn may not ear out very well - even with proper soil. Also, edge plantings of corn are very hard hit by deer, other animals, and insects. Assuming you have a good population of deer, I would doubt many would ever ear out as the corn will be thouroughly eaten by mid August. Also, corn requires a 6.5 ph to do well, it takes at least 3 months for lime to have much effect on the soil. If the hay has been removed off the feild - and is not a legume (clover/alfalfa) over a period of years, you can bet the Nitrogen (N) level is very low, unless the farmer has been fertilizing every year. Corn requires at least 100-200 lb of N/acre to ear out, plus P&K, all this fertilizer makes the ground even more acidic. Lastly, as a result, corn can be an expensive endeavor to get a good crop compared to other food sources.

If the farmer's fields are alfalfa hay, or horse type hay - I'd go with clover (ladino/red/or white) There's nothing wrong with the packaged deals either. If the farmer already has clover - concentrate on a different food source like alfalfa or even wait till fall and plant winter oats, rye, or winter wheat. Its good to offer something a bit different than the farmers in the area if you can.

Of course you should soil sample, but don't get too hung up on it. Most clover will grow OK with ph of 6.0 and oats/rye will grow as low as 5.0ph. Alfalfa and soybeans are another story and need near 7.0 ph to well. In any case, if the ground is rocky, and the feilds haven't been worked in a while, you can bet it will need lime and probably at least some Phosphorous, K levels are usually decent enough to plant in most areas. My point is, an acre is like 45,000 square feet. In a 20 ft strip, an acre is like over 2000 ft long!! So... plan on putting down a couple ton of lime/acre and 200-300 lb of P&K. (no, or little N if planting clover) it will not cost much.

In my area, the soil is very acidic by nature - the soil test only told me what I already knew - LOTS of lime was needed - like 8000 lb/acre to get near 7.0 (mine was 5.0ph). Also, I was told by my local extension agent, that the soil can only absorb 3000 lb/acre of lime per year,at best. You may be able to tell if the soil is acidic by observing what types of plants currently do well on the land. For instance, daisys and wild carrot thrive on acidic land - milkweed and lambsquarters like a more neutral Ph.

That being said, the $10.00 for the soil test is a good investment anyway - if you plan to work the land over several seasons - at least you'll know where you started at.

Good luck - its kind of fun planting - but know what you could be in for before you choose a crop.