The Mercer Island Reporter has this article about a recent study of the island's invasive plants. The survey of the island found that it is home to 12 of the 91 noxious weed species listed by King County. Invasives now cover over 200 acres, with English ivy (Hedera helix) and Himalayan blackberry (Rubus discolor) having the biggest impact. Parks and Recreation staff on Mercer Island, which is part of Washington state, also noted other species, such as English holly (Ilex aquifolium) and cherry laurel (Prunus laurocerasus), that are not as common and would likely be easier to eradicate. Complete removal of all of the listed invasives would cost an estimated $50 million; this likely includes some restoration.