Pond Aeration System for Controlling Pond Weeds
The Perpetual Pond Weed Problem:
Fertilizers
- The cause of excessive aquatic macrophytes (plant) growth and algae in ponds and lakes is an abundance of plant nutrients (fertilizers).
- Fertilizers include phosphorus and nitrogen, carbon dioxide, minor nutrients such as sulfur, and various micronutrients such as iron, manganese, magnesium, zinc, molybdenum, cobalt, etc.
Pond Weeds versus Algae
- Nutrients cause the growth of either pond weeds or pond algae
- Pond algae shade the water therefore pond weeds cannot grow.
- If the problem is excessive pond weeds growth, the weeds take up the plant nutrients in the water therefore the algae cannot grow.
- Some pond weeds such as water milfoil and hydrilla, get up to ninety percent or more of their nutrients directly out of the water instead of the sediment.
- Ponds and lakes naturally shift every few years from weeds to algae or from algae to weeds. It all depends on what becomes established first in each season.
The Problem with Herbicides
- Herbicides kill pond weeds
- Killing pond weeds increases nutrient stockpiles and often results in algal blooms. It’s a dilemma that all pond owners face!
- Herbicides ruin water quality as the dead weeds rot and release the plant nutrients they have taken up. As they rot, they also consume oxygen, causing a massive release of phosphorus and nitrogen from the bottom organic sediment (muck)
- Fish kills often occur as a result of the associated oxygen depletion
- Herbicides do nothing to remove muck (nutrients), nothing to improve water quality, reduce odors, or improve fish growth or health
- The USGS cites pesticides as a “potential concern for human health if they affect a drinking water source or occur where there is recreational use”
- Herbicides are also a potential concern for aquatic life. (Robert Gilliam et al, 1999) There are hundreds of publications on the dangers of herbicides
If you kill all the weeds without eliminating their cause, the plant’s nutrients will still be left in the water. The pond weeds will quickly return, unless algae can shade the water before the weeds are established. Then you have a pond or lake full of algae. If it happens to be blue-green algae, it can extract nitrogen and carbon dioxide directly into the atmosphere. Blue-green algae can increase nitrogen coming into a lake up to eighty pounds per acre each year!
How can I control Pond Weeds?
Reduce Nutrients! Limit Pond Weed Growth!Pond weeds and algae decline as a result of nutrient reductions. All submerged aquatic plants and pond weeds must absorb their major food and carbon dioxide from the water column not through the roots.
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