they can be simply stopped growing
From wikipedia:
Kudzu is an invasive plant in the United States. It has been spreading in the southern U.S. at the rate of 150,000 acres (610 km2) annually, "easily outpacing the use of herbicide spraying and mowing, as well increasing the costs of these controls by $6 million annually".[1] This claim, however, has recently been disputed, the United States Forest Service estimating an increase of only 2,500 acres per year.[2] Its introduction has produced devastating environmental consequences.[3] This has earned it the nickname, "The vine that ate the South".
Note they dispute the rate of expansion, not the cost. How many stories of GMO plants pollinating non-GMO plants? When it comes to fixing things, I think scientist have a very limited view of what could go wrong. They may say the roots can not eat Plastic Pipes, that the Sap will have no effect on anything. But the truth of the matter is that until they introduce something, they do not know the consequences of their actions.
Scientist want to help, that is their job, to come up with solutions. It is the job of the people to understand, and to ensure the scientist understand, what could go wrong. Then for all to sit down and re-think the solution, or to run with it, like the atomic bomb. There was actually quite a lot of talk, and fear, about what would happen if they built it and used it. A lot of the fear fortunately did not come to pass, (the blowing the atmosphere into space).
If the plant worked as designed, then absolutely no problem. But what, what if id did not work as planned? Kudzu whether 150,000 acre a year spread or 2,500 acre a year spread, it is still spreading despite all the money being spent to stop it.