PROBLEM:
Many leaders in our communities have been uneducated on the important benefits of grass in our environment, and have inadvertently believed that grass uses too much water. As a result, legislation is being brought up and in some areas passed and funds are being spent to remove grass and lawns and replace them with xeriscaping.
However to do so causes something called the Environmental Warming Effect. Scientists have found, by analyzing satellite data, that surface temperatures in cities can get up to 20-30°F higher than in their rural surroundings, and areas of extreme heat have risen on average by 2°F in the last 20 years (global warming). The belief is that this is caused by the removal of green grass and plants in suburban environments.
SOLUTION:
Grasses are invaluable assets to our planet and its inhabitants. With a better understanding and appreciation for grasses, we may find a real solution to GLOBAL WARMING and most likely will never look at our lawn the same way again.
To make a significant impact on water conservation and optimization, it would be better to increase funding of conservation and optimization practices aimed at lining or piping agricultural and residential water delivery systems (i.e. reservoirs, rivers, canals and ditches) than to waste money trying to RIP THE STRIP or remove grasses or plants from our suburban environments. Most of the unimproved delivery systems in agriculture have evaporation or seepage losses of 30% to 50%. Water applied only in the proper places will save water and increase consumable suburbian use.
Grasses have a natural ability to go dormant, a kind of plant hibernation, and still provide many of its natural benefits. Lawns that are watered deeply once every 4 to 6 weeks will be maintained in a dormant state until drought or lack of water can be improved and the green lawns additional benefits restored. Money would be better spent on educating the public on the benefits of watering less during dry periods. “Grass does not waste water, people do”.
GRASS FACTS: [1]
Properly maintained turfgrass does more for the environment than most other plants including oxygen production, air and water filtration, carbon sequestration, ambient temperature insulation, and erosion prevention.
Grass absorbs ozone and carbon dioxide and, through photosynthesis, converts them to oxygen.
A 2,500 square foot lawn produces enough oxygen for a family of four.
1 acre of grass produces up to 9 times more oxygen than other plants.
Grass lawns improve air quality by trapping airborne dust particles and other contaminants.
Grass lawns filter contaminants from irrigation and rainfall, improving water quality.
Contaminants and dust particles trapped by grasses are neutralized and decomposed into a type of mulch/compost which returns organic matter to the soil, making it more fertile.
Grasses are a natural noise pollution reducer, providing sound insulation and reduction in rural environments.
Between 81% and 90% of the carbon captured in the average suburban landscape is captured by the lawn.
Recent studies at Ohio State University have shown that lawns can remove and store twice the amount of carbon from the air in a year then a tree can in 10.[8]
Grasses provide for a healthy environment in the soils. As carbon is deposited into the soil, it contributes to recharge of soil organic carbon and can have a profound influence on ecosystem sustainability, soil fertility, and soil structure.
Home landscapes that include grass lawns, trees and shrubs can reduce the air temperature outside, and inside the home by up to 15°F.
Turfgrasses, shrubs and trees cool the air by absorbing solar radiation through a process called evapotranspiration. As much as 50% of the heat of the sun falling on the turf will be absorbed and eliminated through transpiration.[8]
A study by the University of Manchester has found that a 10% increase in green space in urban areas would reduce urban surface temperatures by up to 4 degrees. This would have a major impact on countering the "heat island" effect so common in large urban areas.[8]
The cooling effect of grass can lower air conditioner usage, thus reducing pollution and energy costs caused by power generation.
Turfgrass reduces energy usage by up to 25% on a national level due to its cooling effect during the summer and insulating effect in the winter.
Grasses make up about 26% of the plant life on earth.
Turfgrasses protect and allow for recharge of the underground aquifers, while asphalt, concrete, and various forms of xeriscaping cause water runoff.
In general, grass can go up to six weeks without water, depending on the condition of the lawn, soil and other environmental factors. This is its dormant state, a kind of plant hibernation. It takes about two weeks of adequate moisture to revive dormant lawns.[8]
More and more studies are suggesting that by growing more vegetation, we get more rain.[6] Rain follows vegetation.
Grass transpires water into the air, increases humidity, which leads to rain, and decreases pollutants.
Grass-covered surfaces help prevent erosion by keeping soil in place with their root systems. Grass is more effective at binding soil than any other plant.
A healthy lawn can increase a home's value by up to 20%.
Spending time on a well manicured landscape increases mental health and personal well being.
Lawns encourage recreational activities that contribute to good physical health.
Owning a lawn provides a person with a safe place to play, socialize, relax, and spend time with family.
EXPANDED EXPLANATIONS AND DETAILS
The Air We Breathe [2]
Healthy lawns absorb carbon dioxide and ozone from the air and replace it with oxygen.
One 50-foot-by-50-foot (2500 SQ FT) patch of turfgrass produces enough oxygen for a family of four.
Grass transpires water into the air, increasing humidity and decreasing pollutants.
One acre of grass produces up to 9 times the oxygen of an acre of other suburban plants.
Grass sequesters on average 1000 lbs of carbon per acre per year.
Erosion Control
Grass is more effective at binding soil than any other plant.
Grass controls runoff by slowing water velocity, allowing it to soak into the soil.
Roots increase water storage capability by creating pathways through soil and adding organic matter.
Root systems also penetrate and hold on to soil, trapping essential nutrients.
Energy Conservation
Turfgrasses, shrubs and trees cool the air by absorbing solar radiation through a process called evapotranspiration.
The cooling effect of grass can lower air conditioner usage, thus reducing pollution and energy costs.
Turfgrass reduces energy usage on a national level due to its cooling effect on the environment.
Temperature Modification
The average city temperature is hotter because buildings and streets hold heat overnight (the urban heating effect or environmental warming effect).
On a summer day, a sidewalk temperature might reach well above 100°F, this heat is stored, whereas a lawn surface will likely remain around 75°F.
Turfgrass is an evaporative cooler, which is why grass temperatures are cooler than asphalt and concrete.
Water Purification and Conservation
The biology of turfgrass turns lawns into a perfect natural water purifier.
Water travels into underground aquifers via the grass’s root zones.
Soil microbes break chemicals down into harmless materials—including pesticides.
The root zones of thick, healthy lawns help clean passing waters and reduce runoff to nearly zero.
Asphalt and cement surfaces transfer rain, snow and water away from the underground soil profile by runoff and reduce or eliminate the underground ecosystem, filtration system and aquifers.
Allergy Control
Mowed turfgrass helps control seeds and spores, dust pollen from weeds and populations of stinging and biting insects.
A well-maintained lawn will catch pollen and other allergens sequestering them into the soil.
Grasses prevent weeds from sprouting, and causing allergic reactions.
Some weeds, like clovers, attract bees, whose sting can produce allergic reactions.
Beauty and Curb Appeal
Lawns serve as the perfect canvas for landscaping creativity and excellence.
Healthy turfgrass makes and completes an inviting setting for the whole family.
Turfgrass organizes and pulls together all of your landscaping components, providing visual coherence.
Yards are the first thing people see when walking up to a property, giving a first impression that conveys hospitality, beauty, and warmth.
Home Value
Lawns are typically a major component of any highly valued home landscape.
Landscaping a property properly can increase the value of a home by 10 to 20%.
Turfgrass also gives potential buyers the perception of a place where they can not only enjoy the home but also live life outdoors.
Noise and Glare Reduction
Noise and glare are both reduced by the surface characteristics of turfgrasses.
The surface of turfgrass is far superior at absorbing sounds than bare ground, gravel, pavement and other hard surfaces.
It’s possible to maximize noise and glare reduction benefits by integrating a landscape with turfgrasses, shrubs and trees.
Recreation
Turfgrass offers a low-cost way to provide safe recreational surfaces for kids and adults.
Family picnics, adult gatherings and backyard sports are all bonding experiences.
Quality parks and sports fields can build community pride and provide endless interest and entertainment.
Recreational activities and leisure time spent on turfgrass can improve mental and physical health, something that’s vital to modern society—especially in densely packed urban centers.
ARTIFICIAL TURF [3]
While it is hailed for its water-saving benefits, artificial turf has its own environmental drawbacks. It is a petroleum-based product that creates pollution and waste in the manufacturing process. And, while it is often made partially with recycled materials, it is not biodegradable.
Environmental Concerns
There are several environmental concerns associated with artificial turf including loss of wildlife habitat, contaminated runoff and migration of synthetic materials. Contaminants that are harmful to aquatic life, such as zinc, have been found in stormwater runoff from artificial turf. Both infill particles and broken synthetic grass fibers can migrate away from yards or playing fields, contributing significantly to microplastic pollution in surrounding soils and waterways.
Biohazards
Unlike real grass, artificial grass will not organically breakdown pet urine, blood, or other biohazards. Owners will have to regularly hose down the area with water to keep away any lingering odor and to prevent growth of bacteria and germs. To get urine smells out of artificial turf, you'll need a cleaning product with enzymes and live bacteria that break down the source of those tough ammonia odors.
Safety Issues
Artificial turf is less forgiving than natural turf, there is an increased risk for injuries due to falling, twisting, and burns.
Heat Issues
Artificial turf can become much hotter than natural grass on a warm day. Experts note that high temperatures may lead to potentially life-threatening heat-related illnesses for users, especially athletes. A number of studies have measured high temperatures on artificial turf, some as high as 160ºF.
Water Issues
Though artificial turf does not need water to survive, many have found that it will need up to the same amount of water as grass due to needing to be washed and cooled regularly during warmer months. If not washed and cooled regularly, artificial turf can rot and melt, reducing its functional life.
SCIENTIFIC RESEARCH AND EXPLANATIONS
URBANIZATION [4]
Urbanization, or the growth of population in and size of urban areas, has been increasing substantially in recent years. There are now more people living in urban areas than in rural, world wide, and is over 80% in the United States. With urbanization comes an increase in the amount of buildings, concrete and asphalt, and a decrease of plants and grasses.
The many scientifically proven benefits of turf grasses in urban centers include producing fresh oxygen, capturing rainfall, reducing stormflow and erosion, protecting watersheds, filtering pollutants, and more. All of this while they also provide families and pets an outdoor space to enjoy. As urban and suburban areas continue to grow, city planners and inhabitants should seek, and find, even more value in maintaining urban green spaces, including lawns. This is particularly necessary as the bigger the urban areas get, the more plants and green spaces will be needed to counter carbon emissions, temperature rises, and noise pollution, etc.
OXYGEN PRODUCTION
Home and building construction practices often remove, destroy, or significantly impact the health of native soil systems in urban and suburban areas, and the high carbon sequestration rates and fibrous root systems of turfgrasses are one of the most effective ways of returning soil structure to a more natural state. Plants, including grasses, do this by capturing atmospheric carbon dioxide and using solar energy to convert it into complex carbon compounds, primarily sugars. This carbon can be deposited into stems, leaves, and roots where it is used for growth and development, but it can also be captured in the soil as aging plant roots die off and new ones are produced, thereby removing carbon from the atmosphere.
There are an estimated 40 – 50 million acres of urban grasslands in the United States alone, and recent research indicates that grasses managed in urban settings are a net carbon sink for atmospheric carbon dioxide even after accounting for maintenance emissions. Furthermore, carbon sequestration has been proposed to slow atmospheric carbon dioxide enrichment, and soil is the second largest global pool of carbon.
Carbon modeling research of a typical suburban home on a half-acre lot, landscape beds, shrubs, trees, and a grass lawn indicate that between 81% and 90% of the carbon captured in the landscape is captured by the lawn.
In a recent research study of a typical metropolitan area, low and medium-density residential lots account for over 50% of carbon captured in urban green spaces.
In the same study as above, residential lots and open spaces such as golf courses, parks, and cemeteries had the highest carbon density per unit area when compared to other land-cover classes such as meadows and deciduous forests.
Research suggests that grasses can accumulate and deposit carbon into the soil by approximately one-half ton of carbon per acre per year for 30 to 40 years.
Net carbon sequestration rates in urban lawns have been estimated at between 200 and 1,800 lbs of carbon per acre per year.
Research modeling of carbon sequestration by lawns indicates that lawns in the United States alone can sequester between 12.5 million and 95 million tons of atmospheric carbon dioxide per year. That’s equivalent to the annual emissions of between 2.4 million and 18 million typical passenger vehicles.
The leaf density of grass ranges from 3.5 million to over 900 million shoots in a typical 5,000 sq. ft. lawn.
The total root length in a typical lawn has been shown to range from 66 to over 3000 meters of root length per liter of soil. That’s equivalent to 0.2 to 1.8 miles of root length per liter of soil.
ECOSYSTEM [10]
There is another lawn “life” that exists right beneath your feet. This life just happens to be going on quietly underground while families and kids enjoy all that grass lawns have to offer on the surface.
There is a living, thriving, and breathing abundance of life that lawns support just beneath the surface. From plant and soil processes to arthropods and microorganisms, grass lawns sustain a wide range of life in urban and suburban neighborhoods all over the world.
As carbon is deposited into the soil, it contributes to soil organic carbon and can have a profound influence on ecosystem sustainability, soil fertility, and soil structure. Urban and suburban cities in many areas of the world are often developed on former agricultural land. As neighborhoods and communities are developed, hundreds of years of organic carbon deposited by plants are stripped off during construction practices so that homes and roads can be built onto the underlying mineral subsoils. Planting grass lawns, trees, shrubs, and other plants is the most effective way to return these disturbed soils into a more native state. The carbon deposited by these plants improves soil structure and aggregation, creates pore space for water and oxygen, and improves runoff capture. It also helps to promote growth and development of essential arthropods and microorganisms in the soil.
Managed lawns can host as many as 52 different arthropod families, with over half of them representing beneficial insects such as predators and parasitoids.
Researchers in the United States found over 330,000 arthropods in 20 home lawns within just a 3-month sampling period.
Ants are important providers of ecosystem services and are abundant and diverse in managed lawns.
Up to 28 genera of nematodes can be found in home lawns including bacterivores, predators, omnivores, and plant parasites.
HYPOTHESIS WITH MERIT [5]
Many studies show that the humidity produced by plants attracts rain. If we continue to remove large areas of green plants and replace them with large paved areas — gravel included — we reduce the capacity of our entire urban area to produce the humidity required to attract rain.
This effect is easy to see, as the rain clouds daily build into promising forms and simply pass us by. If we are concerned about our water future, shouldn’t we be trying to entice rain?
Conclusion
Based on years of experience, research, and testing learned from agriculture and our business experience, associated with the turfgrass sod production industry, we have come to know that turfgrass and vegetation is essential to the growth, ecosystem, health, and well being of urban areas. Water levels in Utah have suffered through longer periods of drought, and agriculture (turfgrass in particular) has been considered the offender. Based on the above facts and research, the real cause is the removal of plant life from the environment for the purpose of building cities. In order to counter this, we need to, instead of removing grass lawns and replacing them with concrete, asphalt and xeriscaping, add more grass lawns, and plants in urban areas, and educate on better watering techniques, and schedules.
We are a turf producer but we also sell various landscape products including xeriscaping products and decorative rock products. We understand the financial impact that is caused by discouraging inhabitants of the state to install or keep grass lawns to our profits, however it is countered by our sales of xeriscaping products and therefore is not our concern. Our main concern is the environmental impact that is associated with removing grass and vegetation from the suburban and urban ecosystems and environments. Reduction of grass and vegetation is a large part of the true cause of “global warming.” Preserving and increasing grass and vegetation is the main way to overcome the effects of environmental warming and years of poor water conservation practices. Focusing our limited financial resources on improving agriculture and suburban water delivery systems will help conserve water resources better and use water in the right places.
Turf, Grass and Lawn Position Statement Prepared by: Easton Harris, and Kirk Harris of All American Sod, SuperSoil USA, and Ask The Lawn Doctor
Sources
[1] The Lawn Institute, “Lawn Care Basics” https://www.thelawninstitute.org/environmental-benefits/
[2] Pennington https://www.pennington.com/
[3] Sod Solutions, “Environmental Impacts of Artificial Turfgrass” https://sodsolutions.com/industry/artificial-vs-natural-turfgrass/
[4] The Lawn Institute, “Carbon Sequestration” https://www.thelawninstitute.org/environmental-benefits/carbon-sequestration/
[5] Rain Follows the Lawn Posted by jfleck, https://www.thenewhumanitarian.org/news/2013/02/08/will-more-trees-cause-more-rain# https://www.learningfromnature.com.au/drought-proof-increasing-rainfall/
[6] Science.org, “Influence of Land-Surface Evapotranspiration on the Earth's Climate“ https://www.science.org/doi/10.1126/science.215.4539.1498
[7] Greenview, “Watering the Lawn” https://www.google.com/search?q=how+long+can+grass+survive+with+no+water+in+a+dormant+state
[8] ScienTurfic https://www.scienturficsod.com/
[9] Our World in Data, “Urban and Rural Populations in the United States” https://ourworldindata.org/grapher/urban-and-rural-populations-in-the-united-states
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