Brooke here. A tree fell the other day, so I’m about to go off on ivy. Again.
A few months ago, a piece on the impending insectpocalypse was going around. One response was to plant English ivy as a habitat. No. Never do this, at least in a garden or a wild area. There’s research which shows that ivy planted against buildings is not only a habitat for bugs and birds, but also serves as insulation. Its ability to chew threw mortar and bring down stone walls is overblown. So yeah, plant this shit against a building and reap the benefits. But never plant this anywhere else, and keep an eye out for spreading or bird-pooped berry volunteers which you should murder with all due prejudice.
Ivy is a thug. It eats and climbs and kills. It denudes the soil and strips it of nutrients that other plants need to survive. In its life cycle, it spreads, then stretches, then establishes itself as a mature bushy plant which envelops whatever it can. The tree that fell was an evergreen that was host to mature ivy, which had almost, but not quite, managed to kill it. Instead, it was a struggling weakened tree that fell over during a storm and crushed our fence. Again.
At the time of writing, I’ve applied my tiny chainsaw and broken down the top third of the tree. Here’s the tree’s own biomass, with shoe to scale:
Here’s the ivy’s biomass, with the same shoe:
This is just the top of the tree. The larger parts of the tree are also swallowed by ivy. There’s nothing left of the tree’s own branches on the lower two-thirds of the trunk. It’s just ivy.
This tree was dying. Ivy can serve as a support structure and hold up a tree for a time, but it’s not a substitute for a tree’s own roots. The tree toppled at ground level, most likely because those roots were dead, dying, or being devoured as plant food for the ivy.
We’ve been cutting back ivy from trees to help them survive, girdling the ivy by chopping out several feet of growth around the bottom of the tree trunks. Unfortunately, there’s so much of it, and it’s got a fifty-year head start, and so many of these trees were already dying when we bought this property. This tree was one of them.
If you absolutely must plant English ivy, do it against the side of a brick or stone building, as it’ll tear right through siding. If you still want to plant ivy and you don’t have a hard-surface building handy… Well, we’ve only got about ten good years left and I guess it makes a decent carbon sink, but so are those trees that it’s murdering. The only other time I’d ever consider planting ivy is if the alternative is to plant kudzu: ivy and wisteria are nearly manageable, but if kudzu ever appears on our property, I’m simply going to save time and burn this place down.
Flying by night 
Porcelain Berry vines are wreaking havoc in my neck of the woods (Northern VA). At first I thought they were grape vines… then something related. They have bunches of fruit that resemble grape bunches about the way wild strawberries resemble the stuff you see in stores. Birds love to eat them although they’re flavorless and spread the seeds everywhere. The insidious part is that they have almost zero nutritional value so the birds eat more and more and more trying to get the nutrients they need.
There was a house in my neighborhood that had lovely beech trees with ivy ground cover that they somehow managed to keep from growing up the trees. Never was sure what blood rites they committed to do that… The other bad thing about ivy is that mosquitoes LOVE LOVE LOVE them – they are perfect hiding spots from the sun during the height of the day and provide just enough moisture for breeding (mosquito larvae need a minuscule amount of water to survive).