Go to almost any park in Seattle and you will find a bright green plant with unpleasantly spiny leaves. Unfortunately, in most situations, the large shrubs are neither of our native spine bearers, devil’s club or Oregon grape. Instead, those-who-you-should-avoid will be the fourth most common, non-native plant by acreage in Seattle, the English holly, Ilex aquifolium. Long known for their wintertime beauty, particularly when sporting their red berries, they didn’t reach their invasive reign of floral terror by themselves; they benefited from Seattle school kids and Lillian McEwan, an early 20th century avid gardener and socialite.
Native to Europe, northern Africa, and southwest Asia, holly trees have long been a popular ornamental, both alive and in boughs, the latter celebrated in song as hall decoration. (There are 574 species in the genus Ilex found from Albania to Zimbabwe.) They made their first appearance in Washington in 1858 (or maybe 1891) in Sehome, when John Barrett planted them. (He was called the Burbank of Puget Sound, a reference to Luther Burbank the horticulturalist who first planted Himalayan blackberries, which seems fitting considering both plants are now problematic.) But it wasn’t until 1927 when Lillian launched the Washington State Society for the Conservation of Wild Flowers and Tree Planting that planting hollies became popular; for Seattle’s children it also became almost a rite of passage.
Although the Society’s focus ostensibly was to “love, conserve, protect and rescue the native plants,” McEwan’s passion was “to encourage the planting of holly trees” with the hope of making Washington known as the Holly State. By providing hollies, the state could slow down the overharvesting (primarily for those hall-decking boughs) of the east coast’s native hollies. Planting hollies might also reduce the effects of the “shiftless ne’er-do-wells who make a living by going into the woods and taking other peoples’ property,” she wrote. [Quotes and details from Al Smith’s “How Washington Nearly Became the Holly State,” Douglasia, Winter 2013.]
In early December 1927, Lillian began a campaign urging Seattle children to collect their family’s Christmas holly berries, as well as those used in street decorations or sold at florists and groceries. The seeds could then be planted in shallow boxes and, six months later, the Society would appeal again to the green-thumbed youth to take their seedlings and plant them by the thousands. (I have a vision of a determined army of holly-smitten Seattle youth scouring the street for every unclaimed berry. Woe be to any adult who prevented these Johnny Hollyseeds from saving the sacred Christmas plant.)
If all went well, and the seed soldiers from the Boy Scouts, Girl Scouts, Camp Fire Girls, the Mountaineers, and the other organizations would spread their progeny. “It will be but a short time before Washington holly takes its national place with Seattle’s babies and the Douglas fir," said Lillian, whatever the heck that means. Or at least hollies would grace Seattle parks, a plan endorsed by the U.S. Forest Service, the Seattle Park Board (head gardener Jacob Umlauf called hollies a “bird’s best friend,” in part because “no cat can climb a holly tree”), and the dean of the UW College of Forestry. Al Smith notes that an estimated 30,000 children planted hollies in city parks—primarily at Lincoln and Seward—in the seven years Seattle kids did their civic and horticultural duty.
Clearly Lillian and her army of planters got what they wanted. A 2005 report listed hollies as the third most common tree in Seward Park, after the native Douglas fir and big-leaf maple. The spiny plants are found in every county west of the Cascades and 93% of Seattle parks. Nor was Lillian’s success limited to spreading hollies in Seattle parks. Ninety percent of English hollies sold in the U.S. are grown in the Pacific Northwest, generating at least $5 million annually in Washington.
Unfortunately, hollies have achieved another level of notoriety. They are listed as a noxious weed by King and Whatcom counties and have made it onto Alaska’s list of top-ten worst invasives. Their dense thickets suppress germination and growth of native trees and shrubs and create habitat unfriendly to many native animals. The plants also spread easily (birds have replaced Seattle children in this task), are hard to eradicate, increase fire risk, and have berries toxic to children.
Basically, hollies are a prickly, unpleasant pain in the ecosystem that contribute little to the overall good of the community. Various groups, including EarthCorps and Seattle Public Utilities, have been attempting to control and eradicate holly in green spaces around the city but as often happens with invasives, the plants continue to thrive. We have no one to blame but ourselves and one overenthusiastic socialite.
A followup: I first read about the hollies in a forthcoming book about trees by Taha Ebrahimi, Street Trees of Seattle, which come out in 2024. I should have mentioned this when this newsletter was originally sent out.
In case you wondered, or were interested, many of my books are available to purchase through my website. Thanks.
Excellent article of local interest and w a nature angle. Well done.
We have two holly trees behind my brother's Seattle house which I've always loved for the winter beauty and the birds they attract - they have been kept in check by heavy harvesting in the winter holidays for gifts to neighbors. Interesting to know they are in the same class as blackberries, which I love for pies but admit are a constant menace.