February 14, 2013

Pros + Cons: Artificial Turf and Live Grass Fields

I've designed, planted, and installed playing fields in public art and playground projects for over 30 years in NYC, Newark, and Boston. Outside the US I've helped with grass fields, gardens, and playground projects in Cuba, Mexico, and Toronto. All public, high traffic projects with active play. I've monitored and studied the fields I've designed, installed, or helped with, some now over 20 years old. Based on this experience I would say almost any product (except a toxic one) has its uses DEPENDING on the conditions you will use it in. Therefore there is no general recommendation here on brands, or types of fields. Live grass, breathable artificial turf, and Astro-Turf all have their place in the world.

Artificial Turf
There are now many brands of artificial turf besides the famous "astro-turf". I've used a lot of "breathable" brands that allow air and water to go through the turf into the soil below. Some we installed with infill (little rubber bits made of recycled tires) and some without. You can find brands that are "cooler". There are many cons to artificial turf but I still install it, because it makes a soft play area in previously unusable spots. You can look for a brand with high recycled content, softer blades of grass, breathable material, and non-toxic infill. Look at the MSDS (material safety data sheet) and look up the brand with CPSC (Consumer Product Safety Commission).

You don't need to water artificial turf and it doesn't need re-seeding or rest, like live grass. Breathable artificial turf can protect and improve the soil below when installed with a green, living systems approach. Topsoil can be conserved, moisture levels can stay stable, worms and soil microorganisms can be protected and improve the health of the soil below over time. This all depends on how the turf is installed, how it's maintained, and how the soil is treated once the turf is eventually removed. Cooler brands are more comfortable. You can buy artificial turf with a high percentage of recycled content and you can also shop around for a softer "blade" of grass. You can ask companies to send you samples so you can feel them.

There is no such thing as "no maintenance". An artificial turf field is just as hard to maintain as live grass. Any object in a public place with moving parts (like blades of real or fake grass, infill) will be high maintenance. Artificial turf needs to be combed and fluffed up and you need to have skilled people do this by hand or by truck. Turf with infill gets messy. Turf without infill gets hard. Infill is the little rubber bits that keep the blades of grass up, and make the turf feel spongy. The little rubber bits accumulate along the lowest points of the field. Piles of infill start to form. The infill gets in hair in clothes. The infill degrades and becomes dust. This dust is made of petroleum and rubber products and isn't healthy to breathe. Even "cooler" brands get much hotter than live grass on a hot day. A "heat island" effect gets set up, where the heat from the sun and surrounding air bounces back up onto you from the field and it is intolerable. Companies know this and are working on it but it's still hot. The infill dust is toxic if it's made of petroleum products. Look it up on the MSDS. You can buy vacuums and brusher-trucks to keep the infill loose and vaccuum up the extra bits, but then you lose a lot of infill over time.  You can't just put it back in, since it needs to be mixed with the turf a certain way in the factory.

Turf without infill gets compacted (packed down) and hard. With maintenance the turf can stay fluffier, but it will be much harder than turf with infill. These infill/turf systems are really designed to be used with the infill. If you buy repurposed turf you can buy it without infill for about $1/square foot. It also weighs less without the infill. With infill it weighs several pounds per square foot, without about a pound per square foot.

Live Grass
In high traffic locations (10+ kids a day) fields need periods of rest. During the resting time, they need to be reseeded, aerated (a fork or a pencil inserted down into the grass loosens roots and compacted soil), and carefully watered.

Live grass fields are beautiful, smell great, attract a wide variety of organisms, and can host multiple species of grasses and small flowers (clover, dandelion) within a living system. When you fall on a live grass field it "gives" to some degree. You don't get a rug burn like you can on artificial grass. It is much much cooler than artificial grass. It provides oxygen and a cooling effect on the air around it.

Even with very good care a live grass field is very difficult to maintain. When people see your field in a resting period they hop the fence and play on it anyway, and allow their dogs onto it, and the rest time is over. It becomes a muddy pit that changes into a dusty hard central circle of dirt surrounded by a little live grass. Any successful public live grass field gets a lot of rest, irrigation (by hand or underground pipes), and frequent re-seeding. Education can help to improve the relationship between your community and your field.

Writing & Photographs by Paula Hewitt Amram. For more info: openroadpark@gmail.com