As you can see below, using USDA & extension averages along with current market data, alfalfa may be up to $100 more profitable per acre than corn and even more so when compared to soybeans.  Enter your own yield and related expenses to help determine your profitability.

Revenue per Acre Alfalfa Corn Soybean
Value of Crop (tons or bushels) $ $ $
Expected Yield
Value of Harvested Crop per Acre $ $ $
Expenses per Acre Alfalfa Corn Soybean
Crop Inputs (Fertilizer, Pesticides, Herbicides, etc) $ $ $
Seeding costs per Year per Acre $ $ $
Cost to Harvest $ $ $
Total Cost $ $ $
Net Profit per Acre $ $ $

Alfalfa Upper Midwest average price in 2012 per ton; USDA 2011 for Corn and Soybean; USDA NASS Quick Stats - 2012 US average Alfalfa Tons per acre; USDA 2012 harvest forecast in bushels per acre; US Midwest States Extension Services; Alfalfa seeding costs are averaged over 4 years, includes tech fee for Genuity® Roundup Ready® varieties.