By Dawn Pettinelli – Extension Instructor Plant Science & Landscape Architecture

Phosphorus is an essential element for plant growth and as such is a component of many fertilizers. Many may not be aware that phosphorus pollution is the number one cause of declining water quality in fresh water lakes and ponds in Connecticut and other states. Phosphorus gets into the water from several different sources including failing septic systems, fertilizer applications, erosion of phosphorus-containing soil particles, and dissolved phosphorus from plant residues.

Phosphorus…Too Much Of A Good Thing

High levels of phosphorus in soil will not harm plants in your yard but it can adversely affect aquatic systems. Phosphorus stimulates the growth of algae and other aquatic plants leading to eutrophication, or lack of oxygen, in the water. Eutrophication occurs as the algae naturally die and decompose, lowering the oxygen level in the water causing fish and shellfish to die. As a result, water quality is diminished and the use of fresh waters is often restricted for drinking, recreation, fishing and other aquatic industries. In some states, 80 percent of water bodies are so affected that they are unfit for human recreation.

Eutrophication may cause serious health risks to both humans and livestock. Algal blooms of cyanobacteria can produce cyanotoxins which are poisonous and sometimes fatal to both man and animals if shellfish contaminated with the cyanotoxin are consumed.

A soil test before you go shopping can save you money; you may not even need phosphorus, or another of other commercial soil ammendments available.