Yield data from a long term rotation experiment located at Arlington indicates that wheat grain yield was greatest when following soybean (see table below).  There have been a couple of questions this year regarding the prospect of planting wheat after wheat.  Yield of second year wheat (2003 column) was similar to wheat yields following corn for silage.  Third (2004), fourth (2005), and fifth (2006) year continuous wheat yields were dramatically lower than the other rotational systems.  The data suggests that growers should plant wheat after soybean first, then corn silage, and lastly wheat.  That is not to say wheat after wheat can't be done, but expect a yield reduction.  

        UW-Extension agronomists suggest that if growers choose to plant second year wheat several management factors should be considered to reduce risk.  First, plant a different wheat variety in that second year that
possesses a strong disease package.  Under no circumstances should growers consider planting bin-run seed in second year wheat.  By planting a different variety with strong disease resistance characteristics you can reduce the likelihood of early disease pressure and significant yield loss.  Also consider using a seed treatment in wheat following wheat.  Be aware that seed treatments are not a cure all for all common diseases in continuous wheat systems (e.g. take-all).  When growing wheat after wheat, increase seeding rates to 1.8 to 2.0 million seeds per acre.  This will aid in stand establishment and increase the likelihood of a uniform stand going into the winter.  Finally, if using a no-till system, planting into a seedbed that is free of living volunteer wheat is important in reducing the incidence of Barley Yellow Dwarf Virus.  Apply a herbicide to kill any living volunteer wheat prior to planting to prevent a “green bridge” for the aphids that vector this virus.