WESTMINSTER WEST — Due to an editing error, there is now a mistake in the letter I wrote about the “wild” parsnip. I had written, “In the Midwest, where the wild parsnip is abundant, land managers say that it is unlikely to 'invade' well established prairie - i.e. it is land disturbed by humans where the plant may become abundant.”
By taking out the words “it is,” and putting the rest of the phrase inside parentheses, the letter now implies that well established prairie is land disturbed by humans; the opposite is what I meant.
That is, parsnip is unlikely to invade well-established prairie; rather, it is land, such as former prairie land, that has been disturbed by humans that invites a plant like the parsnip to become dominant.
In well-established prairie, the diverse vegetation already present makes the parsnip less likely to become a dominant plant.
My point is that when we think of invasive species, we need to consider why a particular plant becomes dominant - it is often human action, such as disturbance of established diverse ecosystems, that is at the root of the problem.