Pond Boss Forums INTRO Questions & Observations Water hyacinth woes: Dredging?

I know that water hyacinths are particularly tough to deal with because they put down seeds that last for years. Get rid of every one, and next year here they come up again. So two questions for PB:

Question one: How deep in the pond will they place seed? Five foot depths? Ten? Twenty?

Question two: How deep in the bottom would dredging have to go in order to take out the seeds? Three inches? Six? Twelve? Or would dredging just spread the problem?

Thanks for your input. I know that water hyacinths, though pretty, don't belong in ponds! And maybe manatees would eat them, but even grass carp aren't enthused.

The seeds go ALL OVER the pond.

But depending on the size and depth of the pond, they will only germinate if they can get enough sunlight. Determine what depth the sunlight will penetrate (Secchi disk), add 3 more or 4 more feet to that measurement and forget about anything deeper.

We get a few every year, but they are easily controlled with spray. Alligator grass on the other hand is near impossible to eradicate.