Frank said: "I can spray one gallon of herbicide in about one hour. For me, that's a days work:)"

Tiffany said "There's a limit to how much one person can maintain."

Whew - I can definitely relate to both of these statements - WHY do I always think I can do about 5 times as much as I actually can???

Frank, who administers the CRP program - FSA? Have they given you any guidelines as to controlling the growth of trees?

Yes the FSA is in charge of the program. They did come out a couple of years ago and told me I should kill the saplings by pulling them up. I was sure that they had no clue (probably an interns first day on the job). This year I called them for help and they never answered my phone call back requests. I believe they are under staffed and the intern found a better job. Local farm suppliers were no help, this is not a farm problem. I would love to "hire" this service out, but no one is in this business. From what I can tell, the Forest Management people (whoever they are) are in the know. However, I think they may be in a different federal department:)

That would be quite frustrating, it seems that they should be assisting you in some way! I wonder if the local Extension Service, or maybe the Conservation District (formerly the Soil Conservation District) people could be of any help.

You need a bigger spray rig with a pump. At work we modified a Gator with a 25 gallon tank and 50' hose with a trigger sprayer. It takes about 8 hours to fill, spray and refill 3 times.
If you can get out there in the Spring when the seedlings are just getting started you can use diquat (Reward) or gluphosinate (Lifeline). They're great for fast top-kill and the gluphosinate has a weak systemic action as well.