Weeds are an artificial category. It is merely a matter of opinion whether or not a particular plant is considered a weed or a desirable native plant. Some weeds are alien species introduced into an environment without their usual predators. They can then grow unchecked and overrun other more balanced plants. Other plants are considered weeds because they just happen to grow faster than most of their neighbors. When one species starts to dominate, the resulting lack of diversity is the antithesis of a botanical garden. Another reason for weed designation is toxicity. This is a public garden, with volunteers that must get in amongst the plants to prune and thin them, so with both visitors and workers in mind, we strive to keep out plants that are known allergens, such as poison ivy and nettles.
