Maybe a scheme such as is used to clear land for soybeans, of get rid of mesquite in Texas. A big thing like a huge tractor drawn flatiron cuts all bushes at goung level.
Of course, the mesquite is turned to charcoal, and peddled as barbecue fuel. Maybe some ingenious entrepreneur will find a way to get make use of ailanthus.
I still get a chuckle out of a bigshot in Georgia braggin about virtues of kudzu when I was stationed there in WWII. Here in S. California, there are Hispanics with herds of goats that eat bushes to keep them from becoming fire hazard. They would do a good job on kudzu, and maybe on ailanthus also.