Help Save Regional Forests

Hamilton Viewpoint: Duwamish Head Greenbelt, Seattle

Seventy percent of Seattle’s forests gone in twenty years? This was the do-nothing projection of forest ecologists. Now, active restoration efforts are battling invasive plants and replanting the native evergreens so critical to slowing stormwater – the number one polluter of Puget Sound.  Unfortunately, invasive “seed rain” keeps re-infesting the hard work of many. Birds eat the berries of English ivy/holly/laurel and European hawthorn, and spread them throughout our regional forests. Nothing stops ivy or holly, and holly is doubling every six years – an exponential spread (http://seedrain.org/). It’s a 100-year time bomb destroying bio-diversity, and these are only a few of the invasive plants threatening native ecosystems, including many nurseries are still selling.

It’s not a sensational forest fire or clearcut demanding media attention, but the neglect of invasives is far more threatening than any midnight chainsaw. If we want to maintain wildlife habitat, timber industries, recreational opportunities, slope stability, property values, and the natural sponge that filters our pollution, then we must enlist all private and public land managers to control invasive seed sources. 

Losing diverse habitat is a serious health concern. Ivy infestations plus a food source (blackberry, unpicked fruit, bird feeders) are prime rat habitat (food and shelter). Lack of high biological diversity is hypothesized to have an increased risk of human and wildlife diseases (http://www.fao.org/docrep/009/a0789e/a0789e03.htm).  Essentially, we’re losing our ecological checks and balances.

Birds spread ivy and other invasive "seed rain."

What can you do?  Don’t let landscapers infect your woods with yard waste.  Don’t cut trees (unless hazardous) or take out stumps. Safely remove invasive plants from your property at the rate native roots are establishing so removal doesn’t affect the stability of a slope. Call a certified geotechnical engineer for landslide concerns (www.seattlegeotech.org/firms.html). Consider “vegetative management” (slowly replacing invasives with native plants) as a proactive approach to stabilizing forested slopes. Washington State Dept. of Ecology offers information (http://www.ecy.wa.gov/programs/sea/pubs/93-31/chap1.html) on stabilizing Puget Sound bluffs. King County Noxious Weed and Washington Native Plant Society (http://www.kingcounty.gov/environment/animalsAndPlants/noxious-weeds.aspx) and (http://www.wnps.org/) have good invasive and native species information. 

There are a number of companies besides Garden Cycles that do native plant restoration in yards and forests, and I happily offer the names of my local competitors — EarthCorps, Applied Ecology, Mariposa Naturescapes, and Greenbelt Consulting. The stakes are too high to misinterpret these warnings as self-interest. 

Northern Flicker spreads beneficial seed rain from native Tall Oregon Grape (Mahonia aquifolium)