Economic

The prevention and treatment of invasive plants is not cheap, and the costs increase as an infestation grows.

Sugarmakers, foresters, conservation groups and landowners are increasingly concerned about the toll managing invasives takes on their budgets. In Vermont, a landowner could spend $200 to $800 per acre - or more - to manage invasives. The cost depends on the degree of the infestation, topography, control methods and contractor fees.

In addition to management costs, lost revenues also cause a problem. For example, a forest that has a high-quality stand of salable timber but a barberry or buckthorn understory will not be as valuable 50 years from now if the invasives reduce native forest regeneration.