Thank you again for the post, Alberta farmer.  I learned from every reply, so many things to think about with weeds.

I can't combine my double crop soybeans now because the stray volunteer foxtail I didn't kill won't let the combine cut it and thresh.

Every little thing we do impacts the way we farm!

I don't want 100% control but 90% is nice.  I might have 85% where the foxtail won't run but that farm was screwed from the planting date.  We chased the combine with the drill and the beans came up nicely but we could not get My AMS on degrade the wheat straw or my crucial burndown on.  What little I sprayed before a heavy rain is worse than where I didn't spray.

There are some great comments above and I would encourage everyone to read them.

Now how do I reduce the Marestail, Giant Ragweed and Poison Hemlock population on that farm...

I am thinking, I am thinking...

Ed Winkle