Why are you pulling all the ivy (Periwinkle, acacia, etc.) out of the Creek-side natural areas?

Unfortunately, many of the plants brought to North America from other parts of the world for what ever reason- as food, as fodder, for aesthetics, for shade, erosion control, etc.- have turned into real pests once released into the wild. These species find their new home even better than their original one either due to warmer or wetter conditions or free from natural controls like grazing animals or insects, and they begin to dominate the ecosystems where they grow. Ivy, both Algerian and English, are one of the worst of these exotic plant species.

As green and lush and pleasant as ivy may appear it is unfortunately one of the most noxious plant species ever brought to North America (it’s originally from Central Asia and came here with European settlers in the late 1700’s).

What happens with ivy in California (and the rest of the Pacific Northwest too) is that it becomes “invasive” if just a little bit of it gets out into our wildlands and public open spaces- it so completely out-competes native plants in creek habitats and forests that it suppresses the diversity and ecosystem health that used to exist in those places. Because ivy can form a dense mat of stems and leaves along the ground, it can block other plants from growing AND the seeds from other plants can’t germinate due to the lack of sunlight, warmth, competition for moisture, and nutrients. Ivy can establish what is known as a “monoculture” where it becomes virtually the only plant growing in an area because it prevents other plants from growing along side of it.

Ivy can also grow up the trunks of trees and into the tree canopy in its search for sunlight. When enough ivy gets up high in the trees, it can cause the trees to become susceptible to broken branches and toppling due to the weight and density of all that tangled ivy mass. There are large areas of formerly diverse forests and riparian habitats in California, Oregon, and Washington that have been completely overwhelmed by “escaped” ivy and are now virtual ivy deserts. And ivy is very difficult to remove once it becomes established because fragments of ivy stems left in the ground can re-sprout to become new plants.