Friday, November 12, 2010

Typha - Cattails, Stormwater Ponds, Roundup, Nutrients In-Nutrients Out

Killing cattails, Typha latifolia with roundup in a sormwater pond and leaving the plants int he pond to decompose is a sure-fire way of being obvious about not understanding nutrient removal (Nitrogen and Phosphorous) and other pollutants from a stormwater facility.

How often have you seen vast stretches of cattails killed by the action of Roundup's active ingredient - Glyphosate - "GLY-PHO-SATE".

Monsanto has often spoke of the safety of Roundup and I've even seen Roundup representatives drinking the diluted mixture.

Does a wicked job on plants though.

Cattails are a pioneer species and quite persistent in their growth patterns being classified as noxious by many agencies though they are a native species here in Florida.

Cattails are one of the most efficient species at uptaking pollutant nutrients such as nitrogen and phosphorous. Typha is also an excellent mechanism for removal of heavy metals and other contaminants from stormwater.

So here in Florida -and elsewhere - by the time Typha is killed back by the frost, Roundup or reaches maturity as a plant, large quantities of pollutants have been removed from stormwater and sequestered in the plants biomass.

It is in this part of the equation where we need to break the cycle of Nutrients In Nutrients Out.

Take roundup, kill the cattails - let them fall back into the pond and all the heavy metals, nitrogen, phosphorous, oils and greases and other contaminants are soon released right back into the water.

Roundup use concentrates nutrient and pollutant concentrations in stormwater ponds.

Typha and Algae blooms react the same way to the Nutrients In Nutrients Out equation.

Plants are efficient at removing pollutants and cleaning water.

Yet if the plants are killed and allowed to decay in the pond, then all the pollutants and nutrients are re-released right back into the waterbody.

The Nutrients In Nutrients Out cycle must be broken to finally clean stormwater.

Harvesting Typha and removing the species from stormwater ponds is the best long term answer to nutrient removal.

The cattails can then be composted and, after Toxicity characteristic leaching procedure tests (TCLP) the composted biomass can be used as mulch or nutrient rich fertilizer.

Understanding the Nutrients In Nutrients Out cycle is critical to effective and sustainable control of stormwater pollution.

Copper Sulfate and Glyphosate have their rightful place.

To keep ponds sustainable clean - their must also include a Nutrients Out component.

Your thoughts and comments are always appreciated!



  1. Why does it seem that cattails flourish in stormwater BMPs better than they do in natural wetlands?

  2. This is fabulous.Great post!Thank you for sharing.Keep it up!!!

    - nutrient removal