Phosphorus (P) is a nutrient that stimulates plant growth. When it rains, storm water can carry phosphorus-containing soil into lakes and streams. This can result in excessive algae growth, decreased water quality, lower oxygen levels and fish kills.
Western Lake Erie is very shallow and has been subject to phosphorus loading from runoff entering the tributaries. Much of the phosphorus runoff has come from agriculture and other sources within the watersheds of some of tributaries of Ohio and Michigan.
What can farmers, homeowners and others do?
Don’t guess about soil fertility levels. Soil testing is an inexpensive and easy first step to monitoring soil phosphorus and other nutrient levels. Michigan State University has a Soil and Plant Nutrient Laboratory. The county Extension offices have forms and other information about how to take a sample and can process the initial paperwork. Gardeners can use the $20 publication Soil Test Kit Self-Mailer, available through the MSU Extension bookstore.
Fertilize smartly. Most lawns don’t require P fertilizer. Use zero P unless a soil test shows a need for this nutrient. Sweep fertilizer off sidewalks and driveways and onto lawns. Maintain a “no application” zone near the water’s edge.
Prevent soil erosion. Maintain a dense lawn or other vegetation to reduce soil and water runoff. Establish a native plant buffer along the shoreline.
Keep leaves away from the lake and other tributaries. Don’t burn or compost near the shoreline.
Pump out your septic tank (if you have one) every three to five years.
Use cover crops and filter strips in farm fields.
Source: Ned Birkey, Michigan State University Extension