What is lyocell in outdoor gear – and is it as sustainable as we think?

Those of us who love the outdoors by default need to also love the planet and one of the ways you can do that is by ensuring that your gear is made as sustainably as possible. If you’re one of the many trail users seeking to lighten your tread by switching towards in your and , one material that you might frequently see on your clothing labels is lyocell. Lyocell has shown up in a whole host of gear we’ve tried and tested, from the to running shoes, but what is lyocell anyway, and is it as sustainable as we think? Lyocell is the generic name for a plant-based fiber used to make textiles for clothing and household items.

You’ll also see it called by brand names such as Tencel, Newcell and even Excel. According to , lyocell was originally developed by American Enka in 1972, while the 2014 book says it was first developed and manufactured as Tencel fiber by Courtaulds Fibers in the UK in the 1980s. Whoever came up with the idea, lyocell is everywhere these days, from outdoor gear like the to fashion clothes and bed linens.

Lyocell is made from wood – usually eucalyptus but sometimes oak, birch and even bamboo – that is cut down into small pieces and then pulped before being dissolved by the non-toxic chemical amine oxide. The raw cellulose is then spun into fibers which are used to produce yarn. Though different garments made from lyocell will feel different depending on how they’re made and what other fabrics it's mixed with, lyocell on its own is extremely soft to .