Invasive Weeds

Rivers and creeks throughout Sacramento are being invaded. The invaders are non-native plants that have become major weeds. Some of the most familiar of these are yellow starthistle, pampas grass, himalayan blackberry, and Chinese tree of heaven. Others that are not so well known, such as red sesbania, giant reed or arundo, Chinese tallow, and Spanish broom, are also becoming significant invaders.

So what's wrong with having new plants brought to California and the United States? Indeed, not all non-native plants become invasive in wildland areas. But some plants do become invasive and can rapidly expand their territory. These plants threaten the natural biodiversity of our waterways and upland areas as well. They out-compete our native plants, grasses, and trees for water, food and sunlight. They can rob oaks of water because they form deeper tap roots. Yellow starthistle, because of the volume of its seeds and growth pattern, eliminates native grasses and makes trails impassible with its sharp spiney flowers, both for humans and wildlife. Red sesbania, a relatively new invader, is forming extensive monocultures along the edge of the American River and Dry Creek in north Sacramento, eliminating almost all sunlight for shorter native grasses, reeds, and rushes, plants that ordinarily thrive in these areas.

Our wildlife—birds, insects, rodents, amphibians, raccoons, opossum, and deer—depend on native plants to survive since they generally do not eat non-natives that have been imported from distant countries. Some even contain chemicals that are poisonous to wildlife and humans. If these invasive plants are allowed to dominate our natural areas, especially along sensitive riparian corridors (the moist areas next to waterways), the results are likely to be devastating. Native plants will be eliminated and the wildlife that depend on them will have to find new homes. If this occurs on a large scale, it will only be a matter of time until the health of our entire water system is severely threatened as well.

SWW welcomes community volunteers of all ages !

For more information, call Ken Myall, SWW Stewardship Program Manager, at 916-486-2773 or Frank Wallace, SWW Director, at 916-213-4682.

Please send or email volunteer forms to Ken at [Kmyatt@arpf.org]

 We are located at the American River Parkway Foundation Volunteer Center at 5700 Arden Way, Sacramento CA 95608.

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