English Ivy: An (Ob)noxious Weed

February, 2017

English ivy (Hedera helix), a non-native vining plant, is one of the most troublesome invasive species to California’s North Coast. Ivy was originally brought by European settlers as an ornamental garden plant, but it has since escaped and runs rampant on both private and public land. Although ivy spread rather slowly in the beginning, it is now spreading at an exponential rate and little is being done to control it.

Due to our favorable climate, English ivy is spreading into vast areas including forests all over Humboldt County and other coastal counties. Together with other well-known pests, like Scotch broom, pampas grass and Himalayan blackberry, ivy is displacing California’s native plant communities and wreaking havoc on local ecosystems.

Ivy can tolerate low-light forests, crawling along the understory until it comes in contact with a tree trunk, where it will climb high into the canopy looking for light. Here, ivy will flower and fruit. Hungry birds eating the ivy berries help spread ivy far and wide. This climbing, vining mass carries a lot of weight. Together with the added surface area which catches the wind, ivy-infested trees can topple over in a high wind. Ivy vines grow quickly, as much as 10 feet per year, and can continue growing many feet, year after year, from the same vine.

But help is on the way!

A small group of dedicated volunteers, the Humboldt No Ivy League, has been hard at work for the past eight years to remove invasive plant species, particularly English ivy, from Trinidad State Beach and Patrick’s Point State Park. The No Ivy League meets for several hours on Friday mornings in various work locations decided upon by its members.

Since 2013, the No Ivy League and North Coast Redwoods District of California State Parks have collaborated to treat and restore more acres of cherished parkland, expanding the volunteer invasive plant species removal effort from an annual Earth Day event to a monthly event that alternates between both parks. Last year, with help from the No Ivy League, California State Parks secured grant funding from the California State Parks Foundation that allowed us to hire the California Conservation Corps (CCC) for four days this past November to remove ivy from the trees and ground at Trinidad State Beach. In appreciation of our group’s volunteer efforts, the CCC also generously donated one day of work to our cause. (Thank you, CCC!)

The No Ivy League’s work has demonstrated that where solid patches of ivy have been removed, native plants seem to repopulate the area fairly quickly, typically within a few months. Indeed, native plants come back so fast, it is not necessary to plant native plants to effectively restore an area. The No Ivy League is also the genesis of a proposed regulatory change that would ban the sale of ivy in California. Because of their concern over ivy, the No Ivy League went on tour, bringing a presentation to local environmental organizations on ivy. Soon, a petition to the California Department of Food and Agriculture to prohibit the sale of ivy was drafted and organizations, including EPIC, the Northcoast Environmental Center, Humboldt Baykeeper, North Group of the Redwood Chapter of the Sierra Club, and the North Coast Chapter of the California Native Plant Society signed on. The momentum continued to build and other groups, including Humboldt Redwood Co., Green Diamond Resource Code, the BLM Arcata Field Office, Redwoods National and State Parks, and Save the Redwoods League, were also on board.

Here are a few ways public members can help stop the spread of English ivy and restore our native plant communities in Humboldt County:

1—Remove ivy on your own property and cut ivy stems around your trees to keep ivy plants from producing seeds that birds eat and disperse;

2—Join the Humboldt No Ivy League for our Friday morning ivy pulls. For more information, email Kim Tays at kimkat067@gmail.com;

3—Participate in the monthly ivy pulls held from 9 a.m. to noon on the second Saturday of each month at either Trinidad State Beach or Patrick’s Point State Park.For more information, contact Michelle Forys at Michelle.Forys@parks.ca.gov or by phone at 707- 677-3109. Michelle can provide you with the 2017 schedule of monthly ivy pulls or you can check the Times-Standard, Mad River Union and North Coast Journal for notices about upcoming monthly work days; and

4—Contact Senator Mike McGuire and tell him that our state leaders need to do more to protect our California State Parks and other wild lands from the spread of English ivy. His contact information is: 1036 5th St., Suite D, Eureka, CA 95501; Phone: 707-445-6508; Email: senator.mcguire@senate.ca.gov.