Person: Mary Wiedenhoeft
fit into extended and diversified
crop rotations between the
small grain and corn phases of
the rotation. They can either be
underseeded with a small grain
crops in early spring or planted
in the summer following small
• Farmer-cooperators Doug
Alert & Margaret Smith and
Vic Madsen compared corn
following two green manure
strategies: red clover or alfalfa
underseeded with oats (US) vs. a
mix of sunn hemp, sweet clover,
red clover and radish planted in
mid-summer after oat harvest
• Weed biomass in oats in mid-July
was no different with or without
the underseeding at both farms.
• By mid-October 2016, the US
(red clover) produced more
aboverground biomass than
the MSS by almost 1,000 lb/ac
at Alert/Smith’s. The opposite
was true at Madsen’s: the MSS
produced more biomass than the
US (alfalfa) by approx. 800 lb/ac.
• Corn yields were no different
between the two green manure
treatments at both farms.
January 17, 2018
• Winter canola is a common oilseed crop grown in regions outside the Midwest. Due to its ability to overwinter, it may be a suitable candidate for use as a cover crop in Iowa crop production systems.
• Winter canola was seeded at three dates in the late summer and early fall to assess growth, ground cover and nitrogen accumulation by the above ground biomass in two fall–spring cycles: 2012–2013 and 2013–2014.
• Winter canola seeded in early September produced the most growth and ground cover and accumulated the most N in the aboveground biomass in the fall.
• Winter canola successfully overwintered when seeded in early September and mid-September in the 2012-2013 Cycle only.
• Winter canola performance as a cover crop tended to decrease as seeding
July 16, 2015
August 17, 2011
August 17, 2010