Somewhere I read that the Grazon P+D claims a 76-100% root kill with a foliar treatment...
I sure don't want to hire a dozer and root rake on this place.
To add to the above, This is a 100 acre "free lease" for cattle. I'd pay about a grand a year in this area to lease 100 acres, and I have been given 3 years. With that in mind, I don't want to exceed about $3,000.00 to deal with the tallows.
mow em down...run the cattle and spot treat when they sprout...this will ensure the minimum usage/expense on chemicals...and will be the easiest way to do it...the least expensive unless the mower breaks down...