Tree Stewards, trainees and other environmentalists headed out along Holmes Run in Alexandria Sunday to find native and invasive vines after learning how to distinguish them from a slide lecture by noted naturalist Rod Simmons.
First stop outside Beatley Library was an American elm (Ulmus americana) bursting with light-green ripening fruits on the bank of the old Holmes Run channel.
Tree Stewards and others admire an American elm laden with light-green seeds. Photo by R.H. SimmonsDetail of American elm fruit, above, pointed out by Rod Simmons, hand raised, below. Photos by Jo AllenInvasive porcelainberry’s wiry tendrils coil around branches, digging into tree bark as the vine climbs. Nearby, an Eastern rat snake, sunning itself near the sidewalk, found the group disturbing and slithered off.Several wild grape vines (Vitis spp.) have co-evolved with native trees and grow up with the trees, draping themselves over limbs as they reach for sunlight. Unlike invasive English ivy (Hedera helix), with green leaves on the same tree, grapes and other native vines do not harm tree bark.A native grape vine loops over a tree branch on the north bank of Holmes Run.On the north bank of Holmes Run, a beaver felled a tree and gnawed off the lower bark.
