A post application of a fungicide and an insecticide on soybeans can be worthwhile. The application needs to be made at the R3 growth stage for the soybeans. Our data, Table 1, for the two years, 2009 and 2011, demonstrate an approximate $10.00 per acre net increase for the management decision to spray.
Table 1 Fungicide and Insecticide on 2009 and 2011 Soybeans___________
Post Treatment*_____________ Yield (Bu/A)________
Fungicide__ Insecticide__ 2009 2011
Quadris @ 8 oz/A Warrior II @ 1.6 oz/A 54.9 76.0
None None 53.0 70.1_______
*At R3 Growth Stage Source: Twin State, Inc.
Agronology 10 Research Center
Walcott, IA
The R3 growth stage for soybeans is when the pod is 3/16 inch long at one of the four uppermost nodes on the main stem with a fully developed trifoliolate leaf node.
