Nutrients are taken up by the trees or tied up by root-zone microbes, reducing runoff into groundwater.
Analyses show the trees do the job for about half what other secondary treatment processes cost.
Nutrient dumping is reduced and the sprayed trees grow twice as fast as normal. Some trees have grown 60 feet in eight years and now can be cut for timber. And since many trees regrow from stumps, Frederick says they can pay dividends for cities and industries, as well as the environment, for generations to come. When carbonated bottled drinks lose their fizz, they lose their appeal. But now, NC State chemical engineers are developing plastics to keep the fizz from fizzling out.