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Phosphorus Ordinance Pertaining to Lawn Fertilizers

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Phosphate Free Product Label ImageUsing phosphorus fertilizer, in most cases is not necessary and your lawn will not know the difference.

Phosphorus stimulates the growth of weeds and algae causing adverse water quality issues in Ford Lake and the Huron River.

Phosphorus free fertilizer is less expensive than fertilizer containing phosphorus.


Why did Ypsilanti Township & the State of Michigan ban phosphorus in lawn fertilizer?

The Township is under a federal mandate to reduce phosphorus levels in Ford Lake in order to meet water quality standards.

Runoff from residential lawn fertilization is the primary source of phosphorus entering Ford Lake. By limiting the unnecessary application of phosphorus to lawns, the Township can reduce the amount of phosphorus entering the lake.

To achieve that goal, Ypsilanti Township passed an ordinance to eliminate the use of phosphorus in manufactured lawn fertilizers, effective January 2010.


Why is phosphorus bad for the Huron River and Ford Lake?

During normal watering or rainstorms, unnecessary phosphorus applied to lawns is washed into street storm drains, which empty directly into local creeks, the Huron River and Ford Lake – no filters, no treatment process. Once in the water, the extra phosphorus promotes the rapid growth of algae, which in turn crowds out beneficial water plants. As the algae dies off, the decaying process depletes the water of oxygen, harming fish and insects. If the problem becomes severe enough, lakes become clogged with “pea soup” and scum, and fish kills can result.


What is phosphorus?

Phosphorus is a nutrient that stimulates root growth in plants. Phosphorus is naturally abundant in southeast Michigan soils.

The necessary level of phosphorus for healthy plant growth readily affixes to the soil. Plants are very efficient and effective at drawing phosphorus out of the soil.


If we don’t need to add phosphorus to our lawns, why is it in fertilizers?

It is one of the three macronutrients that plants need, along with potassium and nitrogen. Because most fertilizer is manufactured for national distribution, phosphorus is included in the product regardless of the phosphorus content of the soils in the location of use.


How do I know which fertilizer is okay to apply?

Fertilizer Label ImageCheck the label on the bag, where you will see a series of three numbers. The first number indicates nitrogen used to promote top growth, the middle number indicates phosphorus used for root growth and the last number indicates potassium, for strong stems and disease resistance.

To comply with the ordinance, the middle number must read “0” which means there is no phosphorus in the product. In general, check the turf grass fertilizers for zero phosphorus and avoid “lawn and garden” fertilizers, which are very high in phosphorus.


Penalty for applying phosphorus fertilizers

Each violation of the ordinance will be a municipal civil infraction, punishable by a fine not less than $250 per incident. The fine for each violation of the ordinance by a commercial applicator, property manager, independent contractor or agent for any of these entities shall be no less than $500 per incident.


Exception to phosphorus in lawn & garden fertilizer

The prohibition against the application of manufactured fertilizer containing any amount of phosphorus or a compound containing phosphorus shall not apply to general turf areas where a soil test completed within the last three years has indicated that the level of phosphorus in the soil is insufficient to support turf growth.

A level of phosphorus in a soil test that is less than or equal to ten parts per million indicates that the level of phosphorus in the soil is insufficient to support turf growth.

The application of manufactured fertilizer allowed under this section shall not exceed the amount or rate of application of phosphorus or a compound containing phosphorus recommended by the soil test.

Chapter 66, Article IV


Things to know about lawn fertilizer

Once you have selected a non-phosphorus fertilizer, remember:

Store fertilizer in its original container in a dry, cool place prior to application.


Fertilizer is an asset to your lawn, but you must be careful to keep it on your lawn and out of the storm drain system. Sweep up any spills immediately, including any granules on sidewalks and driveways. Never apply fertilizer right before a heavy rainstorm. Clean walks with a broom, not a hose. Remember, fertilizer that washes off your yard and into the street enters the storm drain system, which is a direct connection to local creeks, Ford Lake and the Huron River.


Apply less fertilizer, less often. If you fertilize just once each year, fall is the best time to apply it because it helps your lawn recover and prepare for optimal growth in the spring. If you have a lawn care provider, review your application schedule with them and ask about fewer applications.


Take proper care of your lawn and you can reduce or eliminate the need for fertilizer. Keep your lawn at least three inches tall, and never cut more than 1/3 of the blade each time you mow. Taller grass has deeper, healthier roots, is more drought tolerant, and prevents weed infestations. When you do cut the grass, mulch the clippings back into your lawn. Mulching adds nitrogen and organic matter, which is necessary to prevent soil compaction. Mulching does not cause thatch.

Read the full Phosphorus Ordinance Brochure

State of Michigan Legislature Act 451, Part 85


Charter Township of Ypsilanti  •  7200 S. Huron River Dr. Ypsilanti, Mi 48197  •  (734) 484 - 4700

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