Kelly,
Is APW easy to mechanically control? I really don't want to use chemicals if possible. If I do need to use chemicals, how long does Aquathol K remain?
"Easy" is a relative term, so I'm not quite sure how to answer your question. Sure, it can be mechanically "managed" (vs controlled), but doing so probably doesn't fall under my definition of "easy".
The half-life of Aquathol (endothall) varies with environmental conditions; namely
water-temperature and its influence on microbial activity, since microbial-decomposition is primarily responsible for endothall's environmental fate. In other words, endothall's half-life is extended in cooler water conditions, but water-temps must be warm enough for plant-uptake to occur; so optimum performance hinges on the Goldilocks clause (neither too hot nor too cold).
Bottom line; if you can't accept or tolerate some degree of collateral damage to adjacent susceptible plant species, it's probably best to stick with mechanical management methods.
