Erosion
[ ih-roh-zhuhn ]
noun
1 the act or state of eroding; state of being eroded.
the process by which the surface of the earth is worn away by the action of water, glaciers, winds, waves, etc.
2 the gradual decline or disintegration of something:
3 Each candidate is blaming the other’s party for the erosion of international trade.
Erosion occurs as natural or human-made forces act upon the Earth’s surface, bringing soil and rock at higher altitudes down to lower altitudes.
Going outdoors, can you find evidence of natural erosion at micro- and macro- levels (e.g. smooth rocks and valleys)? Can you find evidence of man-made erosion (e.g. landslides along carved roadways)?
Erosion, despite the placement of wattles, aside Highway 101 in Sonoma County, October, 2022.
Natural erosion around roots caused by a seasonal creek.
Outside School participants noted that some dirt slid from between dried plants on a hillside after a recent rain.
A student explores Wildcat Creek after it rained for the first time of the season. Note the soil mixed with the water in different places.
Small landslides mark a hillside just off a trail in Wildcat Canyon Regional Park.
After a recent rain, we noticed silt settled onto the tops of leaves at Outside School.
Erosion Control
For the 2022 school year, Outside School children have been involved in erosion control projects with East Bay Regional Parks rangers and Urban Tilth.
While we worked on removing English Ivy, Rangers and Urban Tilth worked to remove invasive Acacia trees from the hillside, allowing sunlight to better penetrate the forest, for the benefit of the newly planted native species.
We help create fascines by cutting off and then deleafing straight Willow stalks.
Outside School does volunteer work every Tuesday. Here's the pile of willow stalks we saved for the park rangers and other volunteers to use for creating fascines in October, 2022.
Stakes inserted into the fascines help hold them in place until they begin to take root. Scraping small bits of bark away from the surface of the Willows is supposed to help foster root development in this type of living erosion wattle.
We work on pulling out invasive species, such as English Ivy, Cape Ivy, and French Broom.
We put down erosion cloth (apparently this can be purchased at a store in Hayward, CA for $200 a roll), using ground staples to help hold them in place.
We cut holes into the cloth and plant native plants provided by the rangers, then use a watering backpack to water them if it hasn’t been raining.
Outside School is working to restore this hillside along Wildcat Creek in conjunction with the rangers, Urban Tilth, and other volunteers.
You are welcome to share all materials with credit to Heather Taylor.