Gardening

There are several types of ivy. Boston ivy, Parthenocissus tricuspidata, can co-exist with masonry walls since it mainly stick to their surfaces. English ivy, Hedera helix, the most common type in California, is IMHO a noxious weed that given half a chance will take over large areas, provide tripping hazards for pedestrians, strangle slower-growing plants, attracts rodents and insinuate itself in cracks in structures. Once established, it's drought tolerant and low maintenance so it gets planted a lot. It laughs at Roundup. It took ten years of constant cutting along with new neighbors who also hated the stuff to get rid of it.

I've seen it trained as an attractive bonsai, though.