As for applying fluridone: spot-treatments for small ponds and most lakes are a futile endeavor. No different than attempting to dye only a small area of a pond and expecting the dye to remain isolated in that spot for 4 to 6+ weeks. It won't!
The main objective with fluridone treatments is to get the product sub-surface, even if you're targeting floating weeds. Fluridone degrades rapidly if exposed to direct sunlight. So, definitely DON'T apply it in a topical manner (a la Roundup) to floating weeds.
Also, if you go to the extreme effort that Todd reported above, be careful where you lay that paddle for next several weeks - and DON'T lay it directly on your lawn. Also, if you step on any fluridone that inadvertently drips in your boat, be sure to thoroughly clean your shoes before walking across a lawn. Oh, and definitely don't drain your trailered-boat in a driveway that borders your lawn. And, if your lab loves to swim in the treated pond, be sure to keep him/her out until the product has thoroughly dispersed; or otherwise make sure said lab doesn't shake, lay or roll on your lawn. Did I mention that my lawn frequently has white spots and dead grass in unusual patterns (some even resemble footprints)? My wife still thinks our lawn is simply disease-prone. Isn't practical experience wonderful!
