Combating the "Ivy Desert" - Paper about the invasion of Hedera helix (English Ivy) in the Pacific Northwest, United States. www.hort.agri.umn.edu/h5015/00papers/okerman.htm
English Ivy (Hedera helix) - Description, images, invasiveness in the USA, and control. www.nps.gov/plants/alien/fact/hehe1.htm
Hedera helix Fact Sheet - Description and images. www.cnr.vt.edu/dendro/dendrology/syllabus/hhelix.htm
Ivy Removal Project (No Ivy League) - Project to eradicate the invasive exotic Hedera helix from Forest Park, Portland, Oregon. Information on English Ivy and how to eradicate it. www.noivyleague.com
Poisonous Plants: Hedera helix - Description and images from Poisonous Plants of North Carolina. www.ces.ncsu.edu/depts/hort/consumer/poison/Hederhe.htm
