SUTHERLAND, Iowa — Proper drainage can increase yields by 5% to 30% by removing excess water during the growing season and providing roots with oxygen within the two-day time needed for corn and soybeans. A three-day Drainage School planned Aug. 25-27, at the Northwest Iowa Research farm, 6320 300th St., Sutherland, will teach attendees how to properly drain Iowa soils for maximum crop production with modern methods and equipment. In addition to…