Your magazine still ranks as one of my favorites and I quote often from it, including excerpts in my newsletter.
However, there are several pieces of information that I take issue with in the article “Meet Your Next Tank Of Gas” in the September issue.
Specifically, in the section on miscanthus, the author states it needs little fertilizer. What is little? Are we talking N, P or K or all three? There is a misconception in the public's mind (even in the ag community) that ethanol from biomass somehow is cheaper and more environmentally sound than ethanol from corn.
First, switchgrass, miscanthus and corn are all grass plants. They are not legumes and do not make their own nitrogen. The amount of biomass that each produces is fairly linear in the amount of potassium that is removed from the soil. (Potassium is the more important nutrient in cell structure and growth.)
Simply, there is no free lunch,and we need to stop that misconception. Any biomass crop will fall under the same discipline as corn and soybeans.
Since land and many other factors are fixed costs, the most efficient production will be to get the most tonnage per acre, requiring nutrient management, just like corn and beans.
Paul Fixen, of the International Plant Nutrition Institute (formerly the Potash and Phosphate Institute) has some good information on low and high switchgrass production.
Higher yields remove higher amounts of nutrients. Pretty basic stuff. Miscanthus will be no different.
Tom McGraw, Owner
Midwest Independent Soil Samplers
Buffalo Lake, MN
Send your letters to csd@csdigest.com, or to The Editor, The Corn And Soybean Digest, 7900 International Drive, Suite 300, Minneapolis, MN 55425.