Hi Tyan. If you are using Aquapro (and i believe this also applies to other aquatic glyphosates) the label recommends waiting until the plants have matured and most of the plants are flowering before treatment. Here in IL that seems to occur in July/Aug from what I've seen. I have had great success using Aquapro and Cidekick in treating American Lotus plants late in the summer. To reduce the risk of a fish kill, if a pond is heavily covered, I usually treat 25%-33% of the pond every 2 weeks. When using Aquapro and waiting until the plants are flowering I see very few plants return the following year. Also make sure your sprayer doesnt have so much pressure that the droplets are pushed off of the surface of the leaves.
If you wanted a cheaper than flurodine early season chemical I saw that Navigate lists spatterdock on the label BUT it does say it is "slighly to moderately resistant" to the chemical. I haven't personally tried it but it may be an option. I would contact the company to see what they mean by "slightly to moderately resistant" first though. Hopefully Kelly will be able to give some input on this.
