When determining your herbicide program for spring applications, the stage of the wheat crop should be considered. The majority of wheat herbicides labeled for application at certain wheat growth stages have very short windows in which they can be applied. The popular broadleaf weed herbicides 2,4-D and MCPA are efficient and economical, but can only be applied for a short period of time between tillering and prior to jointing in the early spring. Wheat growth stages and herbicide timing restriction are outlined in a in a post last week (Herbicide Applications on Winter Wheat).
Another consideration you should take into account when planning a spring herbicide application is the plant back (or recrop) restrictions to double crop soybeans. Many of the herbicides listed in Table 19, have soybean plant back restrictions greater than the typical three month time period between spring applications and double crop soybean planting. The soybean plant back restrictions greatly reduce the number of options available to wheat producers who double crop soybeans after wheat.