Treat bur-ragweed immediately after harvest with a tankmix of .5-pint Tordon 22K or Outpost 22K and one #2,4-D per acre with surfactant and do not disturb the site by burning or tilling until the bur-ragweed is brown. Give yourself at least 60 days after treatment before planting wheat.
Surfactant use at high rates improve control substantially.
Tordon 22K and Outpost 22K are restricted use herbicides. Read all labels before application.