Colorful knitted stripes on yarn bombed trees
(Image credit: Bilanol)

Trends come and trends go, and some of them involve “outdoor art” using trees and plants. One new trend is called yarn bombing. This involves using knitted or crocheted yarn to “decorate” outdoor structures, like lamp posts, benches and… trees. Are you wondering whether yarn bombing trees is detrimental? Read on for more information.

What Is Yarn Bombing?

You can think of yarn bombing as tactile graffiti. That’s why it is sometimes called guerrilla knitting or crocheting. It involves decorating trees and other everyday objects on the street with brightly colored yarn using knitted or crocheted pieces. When you see knitting on trees, it is likely the result of someone yarn bombing trees.

Why Do People Yarn Bomb Trees?

Those involved in yarn bombing are thrilled with crocheting or knitting for trees and using this with a way of bringing street art and craft together. They say it is a form of activism that combines an authentic desire to relate to humanity with tactile beauty. The use of yarn has elements of familiarity, intimacy, immediacy, or closeness.

Some say that yarn bombing is about reclaiming cold urban places and making them personal. It involves creating art in a fun and unusual way, causing people to stop in the pursuit of their habitual activities and look at something unexpected, friendly, and beautiful.

Is It Illegal to Yarn Bomb Trees?

In many places, there are no laws against yarn bombing trees and other objects on public property. However, in other jurisdictions yarn bombing is illegal when done in public places, just like graffiti.

For example, a yarn bomber wrapped pieces in Cancun’s Underwater Museum, saying that it was part of a campaign to save the seas. But both the authorities in Mexico and the Underwater Museum discussed pressing charges since the artist had tampered with the museum’s art without permission and damaged sea life growing on the statues in a protected wildlife area.

Is Yarn Bombing Harmful to Trees?

Whether yarn bombing is harmful to trees seemed to be a matter of opinion. Fans of yarn bombing say that their own experiences with knitting for trees suggest that the practice doesn’t injure the trees. They report that their yarn- bombed trees are alive and happy after years of “wearing” the yarn.

But there are those who suggest that covering trees in yarn can hurt the trees. Trees need to breathe, which they do through their leaves. In order to do this, they need roots to absorb water and minerals. If yarn bombing results in yarn that covers a tree down to the soil, it could kill it. If the tree’s root system and the root collar is covered by knitted yarn, the tree could die from lack of oxygen. And some experts suggest that yarn bombing can harm the growth of a tree or attract insects.

Is Yarn Bombing Bad for the Environment?

Yarn bombing by its very nature involves adding an unnatural element to a natural environment. If the yarn bombing covers electrical poles or park benches, the impact is not as problematic as when the knitted artwork is applied to living beings like trees. The potential for damage increases when the yarn bombing remains up over time. There is a real possibility this type of art can injure or pollute a natural environment.

How to Yarn Bomb a Tree

If you feel moved to yarn bomb a tree, do so in a way that does the minimum impact to a tree to reduce any chance of yarn bombing tree damage. Rather than knitting yarn “hugs,” knitted pieces that cover the entire trunk of a tree, make and hang yarn pom-poms like Christmas ornaments. Another good rule is to leave up a yarn bombing for a relatively short period of time. A two-week yarn bombing of a tree is not likely to do harm, while a multiple-year yarn bombing display runs more risks.

Teo Spengler

Teo Spengler has been gardening for 30 years. She is a docent at the San Francisco Botanical Garden. Her passion is trees, 250 of which she has planted on her land in France.