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Extended Review: Allbirds Tree Flyer Running Shoes

We take a close look at the super “green” (and super springy) new Tree Flyer lightweight earth-friendly trainers from Allbirds.

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Before merino, those seeking the warmth of wool sweaters and socks had to deal with itchiness and shrinkage. Before “nut milks” and other non-dairy alternatives, lactose intolerant consumers had to stomach goopy soy milk or gray water called rice milk. Similarly, before the Allbirds Tree Flyer ($160), those who wanted planet-friendly running shoes had to tolerate heavy, non-responsive footwear that lacked the performance of non-bio-based competitors. 

RELATED: The Best Lightweight Trainers This Fall

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Allbirds Tree Flyer Review: The Basics

With Allbirds’ “SwiftFoam,” the Tree Flyer brings performance to the eco-friendly trainer space and becomes the brand’s first solid foray into performance running. Carved into a geometric, edgy, flared heel design for added stability, the bio-based material brings springiness to the New Zealand/U.S. brand’s always fashionable footwear. Add a eucalyptus fiber woven, stretchy, sock-like upper with a recycled plastic hard heel counter, and certified natural rubber tread for a full sustainable package.

(Photo: Adam Chase)

RELATED: Can Running Shoes Become Sustainable?

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Allbirds Tree Flyer Review: What Works

SwiftFoam is far superior to other environmentally-oriented midsole materials—it is also better than the material used in Allbirds’ Tree Dasher. SwiftFoam, made with castor bean, is 48% bio-based and uses a low-heat foaming process and, better yet, feels lively, with energy return upon impact. Compared to the Tree Flyer’s resilience, other bio-based running shoes are energy sucks that merely absorb shock, returning none of the downward foot force back into one’s running gait.

Tree Dasher on Left, Tree Flyer on Right (Photo: Adam Chase)

Allbirds doesn’t compromise the Tree Flyer’s performance to meet its exacting environmental standards. And, unlike some competitors’ “Earth friendly” version shoes from major shoe brands, nor does Allbirds greenwash or assert their shoes are “recyclable” when the recycling requires purchasers to first dismantle the shoe to keep the upper or midsole from the landfill. Would consumers really go to such great lengths?

While many brands have fortunately stepped it up and revamped their manufacturing processes and/or incorporated Earth-friendly materials to reduce their impact on the planet, using ingredients that sound like they’d be a better fit for a cookbook than a shoe recipe—such as banana oil, sugar cane, and rice husks—the performance of the resulting footwear is often half baked and they often run more like flourless torts than sponge cakes. Not so on the Tree Flyer.

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Allbirds Tree Flyer Review: What’s Just Fine

While the Tree Flyer is a marked improvement over other eco-oriented attempts at performance running shoes, at 9.5oz for a men’s size 9, they are heavy enough and lack the pop of a rockered super shoe made of petrochemicals and carbon fiber that the Allbirds are best relegated to training days.

The woven upper fit, while comfortable, runs big in the front of the shoe, and the foot hold is loose enough for a somewhat high stack height and oversized heel geometry that the Tree Flyer didn’t corner with agility.

At $160, the Tree Flyer, what with its carbon neutral, low-impact construction and Allbirds’ sustainable practices of using natural materials and funding carbon projects to balance out its emissions, seems like a fair price, especially when you factor in the consideration that it looks good with jeans and is stylish enough that it can double as a dress shoe in some circumstances.

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A dozen years ago Brooks’ Green Silence were way ahead of their time. They weighed less than 7oz and boasted more than 75% recycled material with biodegradable foam, a burrito tongue and ran like a true racing flat. Allbirds Tree Flyer is the first decent shoe to come along since the Green Silence that nails both the environmental and performance qualities at the same time. Sadly, it is normally one or the other but, thanks to Allbirds’ efforts, the Tree Flyer isn’t an either/or predicament. You can, once again, have both.

Let’s hope the company has set the pace that others will soon achieve so we, as conscientious consumers who don’t want to compromise performance to feel better about our purchase’s impact on the planet can have a win-win. Just as we feel when we pull on a pair of merino wool socks or order a cappuccino with oat milk.

RELATED: Green Triathlete: 23 Ways to Help the Planet