Virginia Regulatory Town Hall View Comments

Department of Conservation and Recreation

Department of Conservation and Recreation

Nutrient Management Training and Certification Regulations [4 VAC 5 ‑ 15]

Action	Amend regulations to address application rates for nitrogen in lawn fertilizer
Stage	Fast-Track
Comment Period	Ended on 2/26/2014

2 comments

All comments for this forum

Back to List of Comments

2/24/14 5:11 pm

Commenter: Eric Miltner, AGrium Advanced Technologies

Nitrogen rate limitations may discourage use of slow and controlled release fertilizers

As described in the “Agency Background” document, page 3, one of the purposes of the VDACS report was to “(i) conduct an assessment of the most effective means to encourage the use of slowly available nitrogen in lawn fertilizer and lawn maintenance fertilizer”. However, the annual nitrogen rate limits in the 2014 draft “Standards and Criteria” may actually have the opposite effect, discouraging the use of slow release fertilizers.

Both the 2005 and 2014 versions of the Standards and Criteria have recommended annual N rates of 3.5 or 4.0 lbs N per 1000 ft² for cool or warm season turf, respectively. The 2005 version had an additional sliding scale that allowed N rates up to 5.0 lbs (cool-season) or 5.5 lbs (warm season) when using slow release fertilizers (pg. 98). This increased allowance recognized the fact that these products pose limited risk to water quality impairment. The sliding scale has been removed from the 2014 version, and the new 80% limitation for slow and controlled release/enhanced efficiency fertilizers (pg. 98) would reduce slow release N rates further, to 2.8 and 3.2 lbs, respectively (rate reductions of 44% and 42% from the 2005 version). Higher annual N rates of 3.5 and 4.0 lbs (cool and warm season turf) would be allowed for readily available N than for slow release N. This seems counter-intuitive from a water quality perspective.

Research has repeatedly shown that slow release/enhanced efficiency fertilizers reduce the risk for water quality impairment, and this fact is recognized by all parties involved in this process. Limiting the rates of slow release N to levels that may not be agronomically sufficient, depending on specific product technology, could actually discourage the use of these products, and encourage exclusive use of readily available N sources instead. This unintended result would be in complete opposition to one of the primary goals of the entire process.

Two potential resolutions exist: remove the 80% limitation in the 2014 version, allowing all products to be applied at the same annual N rates; or keep the 80% limitation, but base it on the higher 2005 rates, resulting in annual N rates of 4.0 (cool season) or 4.4 (warm season) lbs N per 1000 ft² when using slow or controlled release/enhanced efficiency N sources. The latter approach would provide a true incentive to the use of these more environmentally responsible products.

CommentID: 31072

2/26/14 9:47 pm

Commenter: Richard Martinez, RISE

Lower Annual Nitrogen Rates for Slow Release Products will Discourage their Use

It is generally recognized that lawn fertilizers containing slowly available forms of nitrogen provide increased protection against nutrient loss than water soluble/readily available nitrogen products, particularly when used at equivalent nitrogen application rates. It is therefore desirable to encourage the use of products containing slowly available nitrogen. We believe this was the objective of the Virginia Department of Ag and Consumer Services study and report of December 2011, and the subsequent Virginia Nutrient Management Standards and Criteria draft regulation.

Upon review of the documents however, the current draft rule can be interpreted as limiting slowly available nitrogen products to lower annual application rates (80%) than their water soluble counterparts. If this limitation is correct and enacted, we believe that it would discourage manufacturers and users from using slowly available nitrogen. The rule under this interpretation would limit flexibility in use and overall turf quality (also negatively impacting nutrient loss via thinner turf).

The draft rule also recognizes that products containing slowly available nitrogen can be used in a single application at rates up to 2.5 lbs N per 1000 sq ft providing the water soluble portion of the product is limited to 0.7 lbs N per 1000 sq ft, due to their increased nutrient loss protection properties. However, it continues to repeat the 80% annual application rate limit, which would in effect limit a product of this design to one application annually. We do not believe that this was the intention of the rule.

Our suggestion is that either the 80% limitation be removed, or a limit more in line with previous regulations allowing higher application rates for products containing slowly available nitrogen be incorporated. We feel these changes are necessary to achieve the overall goal of increased use of lawn fertilizers with slowly available nitrogen that protect against nutrient loss.

Thank you for your consideration.

CommentID: 31106