Allbirds Tree Flyer review: sustainably made, but a little slack for long distances

Allbirds Tree Flyer: first impressions

The Allbirds Tree Flyer is the latest and lightest road running shoe from the sustainable shoe brand, and although the look and feel are familiar, it's a noticeable upgrade that's more refined than the Tree Dasher released in April 2020.

In terms of materials, Allbirds has done its bit to limit carbon and use of crude oil products. The shoe's midsole is made from Allbirds' SwiftFoam, which is manufactured using 48% castor bean oil to reduce use of virgin plastics. The material is foamed using minimal heat, reducing carbon emissions, and the external heel counter is made using leftover scraps from the process.

The upper is made from eucalyptus tree fibers, the insole is sugarcane-derived SweetFoam, and the heel lining is merino wool. Even the laces are made from recycled bottles.

The Tree Flyer's tongue is fully incorporated into the soft upper, which means no worries about grit and stones. However, this is definitely a shoe to keep for fair-weather road runs. Although there's a reinforced area on the heel, there's nothing to protect the soft toe of the shoe from damage. This definitely isn't a shoe built to handle trail action.

There are no flashy neon highlights or big logos here; the upper is available in a range of solid colors with matching laces, and all shades come with an angular gray-toned sole. Like all Allbirds shoes, it's available in both men's and women's sizes, but there's no difference in style or colors.

Allbirds Tree Flyer: on the road

Although supremely comfortable, the Allbirds Tree Flyer doesn't provide the snug fit you might expect from a more traditional running shoe. The upper is stretchy, which accommodates larger feet well, but means there's a fair amount of movement, particularly when you pick up the pace. You can't compensate for this with lacing, either; the laces have a fair amount of stretch, don't come very high up the foot, and have no additional eyelet for creating a heel lock.

The choice of mainly natural materials means it's also not the lightest shoe around (no nitrogen-filled foam or gossamer-thin nylon here), so you might prefer to opt for something different for race day. However, the Tree Flyer is a little lighter than the Tree Dasher, down from 298g to 287g for a UK men's size 8.5.

It's important to note, however, that Allbirds is a premium brand, and the Tree Flyer comes with a premium list price of $160 / £150. If you're looking for a 'greener' road running shoe with a more snug fit and smaller price tag, take a look at the Reebok Floatride Energy Grow.

Comfort

The Allbirds Tree Flyers are incredibly comfortable, and slipping them on feels like sliding into your favorite pair of slippers

If the Tree Flyer doesn't sound quite right for your preferred running style, I can see it making an excellent recovery shoe. There's plenty of arch support, and the footbed is super soft. It would also be good for everyday city walking , and doesn't look dissimilar to the classic Allbirds Tree Runner (which, despite its name, is actually a casual shoe for strolling about town).

Construction

Allbirds has made clever use of plant-based and recycled materials, and incorporated some smart design tweaks. For example, the sole has a new heel counter to provide motion control for heel strikers, though it's far more understated than the SwallowTail design of shoes like the Hoka K-ST 21, and won't draw attention if you choose to wear the Tree Flyer casually between training sessions.

The Tree Flyer's midsole has a new angular look, and is slightly flared for stability. The SwiftFoam material within isn't at bouncy as a more typical foam midsole, which on one hand means that it doesn't feel unstable at slower paces, but also means it's less responsive when you speed things up, with less energy return.

There are some small, but thoughtful tweaks too. For example, the eyelets are reflective for nocturnal visibility, and there's a small reflective logo on the back of the heel.

Durability

Allbirds has made some smart tweaks that make the Tree Flyer a more durable shoe than the Tree Dasher, including the aforementioned panel on the back of the heel, which protects the one-piece upper from scuffs. We'd like to see a similar patch on the toe in a future iteration, as the Lyocell material is particularly soft.

On that note, if your big toes curve upwards, they will make 'poke' marks in the upper over time as the material stretches, but that's just a fact of life, and the upper doesn't seem to wear through quickly in that area.

The FSC-certified rubber outsole provides a good amount of grip in wet or dry weather, even on slick surface, and thus for in my testing shows no sign of premature erosion.

If you're concerned about smell (a problem some wearers report with Allbirds' casual shoes), don't be; you'll be wearing the Tree Dashers with socks, which minimizes mustiness, and they can be tossed in the washing machine on a cool gentle cycle to freshen them up.

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