Alternative mowing strategies such as “No Mow May” have become increasingly popular lawn care idea in recent years. We thought we would take a few minutes to write about what we know based on research about some of these alternative strategies. Who doesn’t love a little current science to consider?!
What is “No Mow May”?
A “No Mow May” lawn
In essence, No Mow May is pollinator-focused, with advocates emphasizing there are very few flowers blooming in early spring on trees or in landscaping - especially in the northern states - and therefore homeowners should pause mowing in May to allow weeds, like dandelions, to remain in bloom longer. Increasing weed diversity in a lawn, and even allowing the lawn to go to seed, would potentially have a positive impact on pollinator populations. Detailed information about the movement can be found here.
This is a very interesting idea. And frankly, we suspect parts of the approach would indeed be beneficial to early spring pollinators. It is also important to mention both Mike and Sarah from Blue Grass have served on several research committees for the turf industry over the years. And variations of research like this study from Wisconsin have become increasingly popular in the last decade.
As you can see in these studies, there are some promising results. Specifically, the Wisconsin study mentions lawns who participated in “No Mow May” saw three times more native bee species present, along with a more diverse set of lawn plants through May.
One thing we do know is that raising your mower helps to avoid pressure from certain weeds. This image is courtesy of Dr. Quincy Law from Iowa State’s Turf Department. These plots were fed identically. Note the significant increases in crabgrass pressure in the plots that were mowed at the shortest heights.
It is very, very exciting that people are increasingly aware of our impact on pollinators. It is great that urban and rural people are asking what we can do better to care for the critters around us. This is a huge reason why we moved our 4 Step Program to a pollinator-friendly product line-up years ago. Because ultimately, our choices of products and cultural behaviors do matter.
That said, I can honestly say the research on No Mow May is still not conclusive on what the impacts, positive or negative, really are. For example, in the Wisconsin study, is the increase in pollinators specifically because of No Mow May? Or is it because the people participating in the program are less likely to use weed controls at all, and therefore have more flowering plants in their lawn to begin with?
Additionally, for people who would want their lawn to recover after No Mow May, would the increased grooming necessary to help the lawn recover back down to normal heights release more fossil fuels than would have been originally used? The good news is researchers are looking into questions like this, and we will do our best to relay the information as quality research is completed. It’s an ever-evolving world out there!
Remember to never remove more than 1/3 of the green material from grass plants in a single mowing. Large piles of clippings will smother plants beneath.
Dr. Adam Thoms from Iowa State did a great job last week on Talk of Iowa’s Horticulture Day detailing a method called “Less Mow May”. In short, he indicates research is still inconclusive on how beneficial the practice No Mow practice really is, and if homeowners do not manage recovery correctly in June, they can ultimately do more harm than good (like the photo on the right).
As you can hear in the Talk of Iowa link above, Dr. Thoms suggests some better approaches than “No Mow”. To translate Dr. Thoms’ ideas into an internet catchphrase, his philosophy would probably fit into the “Slow the Mow” movement.
What the heck is the “Slow the Mow” Movement?!
In essence, this movement suggests raising mower heights increases green plant mass (thereby increasing surface area for O2 production and CO2 sequestration) and moisture holding capacity, and reduces fossil fuel burning in mower engines.
More notably, there is a lot more data to pull from to feel more confident about the answer to this philosophy. The answer is “most likely yes”, raising your mower and mowing less frequently has a positive impact on the environment.
To illustrate in greater detail, I will turn to this article written by Joseph Fearn from Kansas University, a regular contributor to TurfNet, an industry research digital magazine. I hope you find the reading interesting and informative!
But before I forget, another easy way to impact the environment with your mower is to service the engine regularly and sharpen your blades. An efficient machine consumes less fuel and does less physical damage to the plants in your lawn. Get that mower serviced pronto!
***Sarah taps in Joseph Fearn from Kansas University like a WWE Wrestler Tap In***
Raising Mowing Height Makes Sustainability Sense - by Joseph Fearn (TurfNet Contributor from Kansas University)
Grounds management in any organization is a complex undertaking requiring the performance of myriad tasks necessary to fulfill the desired strategic objectives. For many, if not most of our grounds crews, sustainability is one of those strategic objectives. While sustainability is a moving target based on one’s definition, sustainability for me means decreasing resource consumption while increasing resource service. Too often pursuing sustainability is a complex undertaking resulting in difficult-to-implement operational changes, or misguided utilization of scarce resources, both resulting in poor return on investment. Fortunately, there are ways to manage sustainability that are easy to achieve and cost-effective. To me, sustainability means decreasing resource consumption while increasing resource service.
Simpler is Sustainable
I once participated in a project that most would consider a sustainability one. This project sought to improve the slow/spread/soak performance of a detention pond adjacent to a medium size (300-space) parking lot. The job reworked the rip-rap flow path through the pond, installed several concrete catch basins, and utilized outflow baffling to increase the holding time of run-off water. It was successful at mitigating run-off but was a pricey and complex job. I believe to make sustainability widespread; projects should be easy to conceive, adopt and implement. Sustainable efforts must also have clear objectives, low-price threshold, and readily understandable return on investment from both a financial and organizational standpoint. Devising efforts incorporating these factors will pay dividends and build further sustainability momentum.
Raising mowing height .5” in just this area added 24 cu. yds. foliage mass
Increase Mower Height
Adjusting mowing heights is a common occurrence in grounds/turf management. We alter turf heights to improve turf health, appearance, and playability. In my experience we have rarely raised turf height to expressly promote sustainability nor have we highlighted the sustainable benefits that come from increased mowing height. Here at KU we recently raised our decks from 3.5” to 4” for most of our campus (nearly all our turf is general utility turf). We did this to help us manage a droughty/hot period, but also for the increased cultural/environmental benefits. In one area (157K sq. ft.) adding .5” height results in approximately 24 cu. yds. of leaf mass. My calculations are as follows:
157,000 sq. ft. x .0416 (equivalent to .5” or 1/24 foot) = 6542 cu. ft. total potential volume
6542 cu. ft. x .1 (10% total density of grass blade tissue in a sq. ft.) = 654 cu. ft.
654 / 27 (cu. ft. per cu. yd.) = 24 cu. yds. real grass tissue
Of course, raising mowing height adds significant foliar mass to the turfgrass stand. The increased height adds the cultural benefits of increased photosynthesis, shading/cooling of the turf environment, potentially deeper root penetration, improved resiliency, and some decrease in mowing frequency. Increased mowing height also provides environmental benefits. Turfgrass inherently reduces water runoff, prevents erosion, replenishes air, cools the environment, supports bioremediation of pollutants, and sequesters carbon. By increasing height, we are achieving the increase in resource service half of the sustainability equation.
Decreased Resource Consumption
The other half of the sustainability equation is decreasing resource consumption. A grounds operation in a transition zone may average 36 mowings per year. This quantity of mowing will likely be a large consumer of the team’s resources, if not the largest. These resources include fuel, direct equipment expenses (purchase and upkeep), manpower, and alternative task opportunity cost. While we must consider the cultural benefits of mowing (turf health, appearance, playability, etc.) we must remember there are negative outputs (emissions, wear and tear on team/equipment, etc.). Raising the mowing height will eliminate several mowings annually. This occurs because the rule of thirds applies less frequently at taller heights and tolerance of taller grass as people adjust expectations. Even eliminating 1 or 2 mow circuits a year can decrease resource consumption thereby achieving the other half of the sustainability equation.
Many Small Steps Achieve Big Results
Sustainability continues to be a hot topic in our industry. Unfortunately, it seems it is sometimes viewed as a tool to be taken down from the shelf when needed, then hung up until the next time. Sustainability must be an imperative that pervades every component of our work. We must pursue it directly by increasing plant diversities and decreasing water consumption, but also by constantly evaluating all our work through a lens of sustainability and innovation. Looking for many smaller sustainability options is easier than looking for only big projects. Consider that U.S. households comprise millions of acres of turf and the total turf in the U.S. is even more. Imagine if all this turf was mowed even a bit taller (where possible… some turf must be mowed at prescribed heights for playability and safety)? The resulting leaf mass would be huge, and all the sustainability benefits resulting would be huge also. So as a small step with a big sustainability result, raise your decks and mow a little less often. #SlowTheMow