wes - I'll copy and put below Kelly Duffie's discussion about the herbicide called Habitat so you and others do not have to search for it. It reads:

Information posted By K Duffie and questions by others...

There is (we have) a 1-gal. aquatic & turf labeled glyphosate product called GLYPHOMATE 41 (as in 41% a.i.) in 1-gal containers, and it already contains a surfactant (mfgr is PBI Gordon).
However, I have become a quick convert to BASF's newly registered HABITAT Herbicide (imazapyr) for treating rooted emergent species; especially lilies (if irrigation and potable uses are not an issue; otherwise glphosate is your only option).
HABITAT has demonstrated exceptional root-control on species that are rooted in the hydrosoil. Glyphosate frequently has difficulty providing "great" root control on rooted-emersed plants that grow in water-depths that exceed a few inches. KD

Questions -
1. DO YOU JUST SRAY THIS ON THE LEAVES THAT FLOAT ON THE WATER? THANKS FOR THE INFO?.

2. can this new product "habitat" be effectively used on cattails before the catkin forms?? If so, when?

3. I'm also assuming that this product can "smoke" American lotus. I'm sure the answers are out there, but I haven't been able to visit the site for quite some time.

Kelly Duffie's Reply -
Basically, Yes, Yes & Yes.
HABITAT is an AHAS inhibiting herbicide (for the technically-interested); somewhat similar in mode of action to ROUNDUP (glyphosate), though active on an different enzyme production-site.
Its primary entry-point is through the leaf-surface, although it is also soil-active if applied to terrestrial sites (avoid doing this anywhere near desirable trees). But, when applied directly into aquatic sites, it photo-degrades fairly rapidly.
Although I compared it to glyphosate, it appears to be much more capable at controlling emergent rooted plants - particularly cattails, even prior to catkin formation - and lotus.
As with all herbicides, obtain and read the label instructions (and water-use restrictions) before making any purchases.
Lastly, HABITAT will soon be available in quarts; which are well suited to small pond environments. I expect the quarts (a new container-size) to hit the dock around mid-May 2005.


aka Pond Doctor & Dr. Perca Read Pond Boss Magazine -
America's Journal of Pond Management