Issue 10, August 30, 2019

Phosphorus Law Reminder for Illinois Turf Managers

Who P’d There?:  Phosphorus Law Reminder for Illinois Turf Managers

Are you an applicator for hire who applies fertilizer to lawns?  Does the fertilizer you use contain phosphorus?  What is the big deal about phosphorous?  Phosphorous (P) is a critical macro nutrient required for plant growth. It aids in processes like photosynthesis, it plays a role with diseases incidences, and it is also involved in the reproduction process.  With adequate phosphorous spring green up is better.  Without P turf grass plants are spindly and dwarfed, and often they will have a purple discoloration along the leaf blade as the deficiency progresses.  It is second to nitrogen as an essential plant nutrient that ensures plant function and health.   These functions enable the lawn/turf to be healthy and dense. Knowing that P is important, we must also be aware of legislation that can affect your ability to apply P to lawns. In 2010, Illinois Legislature passed a bill that restricts any applicator for hire from applying phosphorus-containing fertilizers to a lawn unless a recently conducted soil test indicates a phosphorus deficiency. Notably, homeowners are exempt from this requirement.  Areas that are exempt include commercial farms, lands classified as agricultural lands, and golf courses. Product exemptions are discussed below. An Illinois Department of Agriculture Inspector noted that they have found applicators that were in violation of applying phosphorous. Violators can find themselves charged with a penalty of $250 for the first violation. Penalties increase to $500 and $1,000 for second and subsequent violations, respectively.

It is not uncommon to fertilize our lawns throughout the growing season. It is encouraged as it promotes growth resulting in a healthy vigorous lawn. In general, bagged fertilizer for lawns commonly contains phosphorus so it’s important to be mindful of this law. Look on the bag to see what the N-P-K ratio is. The “P” stands for phosphorus. It should be 0 if the product is to be applied to established turf. As mentioned, there are exemptions. According to the act, lawn repair products are exempt. Manure naturally contains a small amount of phosphorus but is exempt as long as phosphorus has not been added to it. Additionally, the product label (provided there is one) must say it is “manure”. The terms “natural” and “organic” are not enough to allow the application. Manure is mentioned specifically in the act.

What’s the big deal? When phosphorus is applied in excess, run-off can occur. High levels of phosphorus in lakes and streams can lead to toxic-algae blooms. A dozen or so states have similar laws.

In cities and suburbs, the incremental runoff of phosphorus from sources like lawn fertilizer—whether organic or conventional—is a serious concern because it feeds algae and weeds in waterways. When it rains, paved roads, sidewalks and roofs rush pollutants into storm drains that lead to waterways. Research suggests that just one pound of phosphorus can feed 300‐500 pounds of algae in a water body. While most algae blooms are generally harmless to humans, decomposing algae and weeds take up oxygen in the water that is vital to fish and other animals. Furthermore, algae and weeds discourage swimmers, anglers, and boaters—and even lower property values. Phosphorus also feeds toxic blooms of blue‐green algae (cyanobacteria) that are occasionally found in lakes and rivers in Illinois. As recently as June of this year, algae blooms have caused beach closings and health alerts in central Illinois. As stated before, applications of any phosphorus containing fertilizer may be made commercially if soil test results justify the need. For more information on the standards for P fertilization for lawn turfs in Illinois, consult this article by Dr. Bruce Branham:

According to the rule, the required soil test shall be conducted no more than 36 months before the intended application. The Lawn Care Products Application and Notice Act (commonly referred to as the Lawn Care Act) can be found here:

Section 5a discusses fertilizer application restrictions.

Certainly, P may be applied at the time of establishment without a required soil test. Perhaps any large stocks can be utilized in this manner. Please keep in mind that in accordance with the Lawn Care Act, phosphorus can be used on newly established lawns for a maximum of 2 growing cycles. Then a soil test would be necessary.

Maria Turner
Michelle Wiesbrook

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