Is yarn bombing trees ok for environment?

Here’s a rather extreme example of “yarn bombing” (which apparently is due to people who knit suddenly going crazy and making “cozies” for things other than teapots and scarves for things other than necks). Assuming the yarn isn’t taken down for some time (months?), is this bad for the tree or other eco factors? It looks cool and harmless (not sure what it looks like after a hail storm or weeks of rain).


If it retains moisture it could promote the growth of disease and/or insect infestation and thus weakening or even killing the tree.

I think it might depend on what type of yarn is used. If it’s a natural plant or animal fiber (e.g. cotton, linen, sheep’s wool) versus a synthetic yarn (e.g. acrylic).

I am a knitter, but I’ve never done yarnbombing. I would assume that people who make those kind of displays would usually take it down after a while or when it starts to look shitty from exposure to the elements. Most of the appeal of yarnbombing is that it looks neat - scraggly bits of torn and felted yarn hanging from a tree is not so attractive.

If they’re left in place for a long time, I think the effect on the environment could be both directly on the tree (in the example in the OP), and the effect of the environment in general (e.g. scraps of non-biodegradable yarn falling off and getting blown all over the place). If the yarn is a natural plant or animal fiber, I wouldn’t be too worried about harmful effects from the scraps/litter.

With regards to Duckster’s point about tree cozies and its effect on the tree, I would think that most wool/animal fibers wouldn’t retain that much moisture. There’s a reason fishermen traditionally wore wool sweaters. Fibers like cotton are far more likely to get waterlogged and take a long time to dry out.

Whenever I have seen this, it has never been a natural fiber. My guess is cost. A skein of synthetic is typically far cheaper than a natural fiber. I can’t see someone spending a fortune to do this.

Even if the yarn itself isn’t very absorbent, it could trap moisture against the bark just because of the small porous structure.

Thing is, if it’s a tree in your own garden, the eco-impact of killing it isn’t especially severe - in fact, it could be an eco-positive, if for example you sequester the carbon in the tree by using the timber to make durable items, then plant another tree to replace one you killed (it will sequester more carbon as it grows).

Obviously, giving a whole forest this treatment would probably be bad.

Actually, the biggest environmental impact is probably the waste of non-recyclable synthetic yarn - there was an energy cost to producing this, and once it’s been ruined, it will most likely just end up in a landfill. In the context of everything else humans do though, probably not a big deal.

My girlfriend took part in this project on the UT Austin campus, it was left up for several weeks with the OK of the university’s head arborist.