Euonymus alata, also known as burning bush, is at least a clear-cut villain, unlike some of the other invasives. I recall spending a long June day collecting vegetation data in an an immense Euonymus thicket, a former estate in Wilton. I did not even observe a catbird, the most common thicket songbird in Connecticut! And beneath the dense bushes, the ONLY plants growing were Euonymus seedlings.
This species must have high-powered chemical defenses. The glossy leaves look almost artificial (and might as well be), no holes where caterpillars or leaf beetles have nibbled. Pickings are slim for foliage-gleaning parent songbirds.
Euonymus everywhere, east slope of Peck Mountain. (Sorry I have no shots of the sea of red in fall)
Euonymus alata, from Asia, is an effective invader of forests, because it grows well in shade, unlike bittersweet, multiflora rose, everlasting pea, and Phragmites. It spreads well by runners as well as seed. Unfortunately, it thrives especially in the mineral-rich, sub-acidic soil of traprock ridges. Because suburban yards on the flanks of the ridge provide abundant seed sources, Euonymus has overrun much of Peck Mountain, in north Cheshire. Formerly diverse and special traprock vegetation communities have become burning bush monocultures. Euonymus is even able to thrive in specialized traprock habitats like ledges and talus. Some rare Staphylea trifolia (bladdernut) and marginal wood fern remains on the west slope of Peck Mountain, but not very much. Connecticut nurseries are still battling the environmental regulators, to prevent an outright ban of Euonymus alata, because this is such a popular, lucrative species for the landscaping business.
Even grows well on traprock ledges
After that Wilton experience and an eye-opening hike on Peck Mountain, I knew we had to get rid of the burning bushes in our own yard. Emotionally, it was not so easy. This is a beautiful shrub, especially when crimson in the fall, and it makes a dense, tidy hedge. The wings or flanges on the stems also look interesting in winter. Our bushes had special meaning because they been given to us by relatives who were dear to us.
Control was very quick and simple, from a practical standpoint. We snipped them with a lopper, and painted the freshly cut stems with Brush-B-Gon (8% triclopyr). For those who simply cannot kill their prize burning bush, thoroughly shearing off the seeds each September, with hedge clippers, will at least prevent further spread by birds.
For illustrations and discussion of other invasive plants, see the accompanying facebook album “Invasives????” (Sigrun Gadwa)