Interactions with Other Organisms

Like many other trees, the English yew can be used by several animals for protection from the elements. For example, a deer species could bed down by the base to escape rain. Because almost every part of the tree is toxic, it is very limited as a food source. See the toxicity page for information on mammals ingesting yew material. The only part that is actually edible are bright red modified cones (see reproduction for image.) This would be an example of a mutualitstic relationship between the bird and the yew. The bird acquires nutrients and the tree benefits by having its seeds dispersed by the bird.

Taxus baccata has long been known as an extremely toxic plant, but it has been found that the producer of this toxin is not the plant itself, but it is a mutualistic fungus! This fungus that produces the toxin is an endophyte, meaning it lives within the tree's tissue. This is a mutualistic relationship because the fungus gets nutrients from the tree, while the tree benefits by containing a toxin that can be fatal to herbivorous mammals. This toxin, called taxol, is described in further detail on the toxicity page.