Driving out the invaders
The enemy goes by deceptively pleasing names: Tree of heaven, autumn olive, mile-aminute, multiflora rose, wineberry and Japanese stiltgrass.
But in the war on invasive species, harsher terms describe what it takes to keep these invaders at bay: Hack and squirt. Kill it first. Go after the females. Manage the big thugs. Burn the field. The key to victory? “Have patience,” said Amissville’s Bryan Lilly, a habitat management specialist and a presenter at a workshop Saturday staged by the Rappahannock League for Environmental Protection. “Any time you’re dealing with invasives, you’ve got to have patience.”
Some 50 participants showed up at the Theatre in Washington for presentations by a pair of front-line habitat experts. The workshop included a muddy-boots tour of the town’s demonstration butterfly trail led by master naturalists Jack Price and Jenny Fitzhugh.
While the Piedmont is home to diverse native plant life, unwelcome invasive species are the bullies on the block, pushing out natives and compromising local fields, forests and gardens. Removal is costly, time-consuming and frustrating, even for backyard gardeners.
But both presenters said control is both possible and practical.
Lilly, a certified arborist and owner of Natural Elements, drew on his plant management experience at the National Zoo to describe the worst of the invaders.
Invasive species come in all shapes and sizes, he said. There are annuals like mile-a-minute and Japanese stiltgrass, biannuals like garlic mustard, herbaceous perennials and woodier foes like ailanthis (also called tree of heaven) and autumn olive. Each requires different techniques and seasons for removal. It’s not as simple as getting out the chain saw.
“You can cut ailanthis, cut it down, and it comes back 10 times worse,” said Lilly. “You’ve gotta kill it first.”
Brian Morse, a wildlife biologist working with the Virginia Forestry & Wildlife Group, agreed, calling ailanthis “the worst invasive tree species in Virginia.” In Rappahannock, Morse also sees autumn olive, multiflora rose, bittersweet and Japanese barberry “on every property.”
Morse described selected case studies of efforts to remove such invasives as fescue and Johnson grass and replace them with native plants and grasses. He advises clients to decide what their land-use goals are first and take a phased approach.
Effective removal often comes down to patient, hands-on work, careful spraying with herbicides like glyphosate or Garlon, and knowing what sprays work when.
Morse offers these tips for clients: • Scout for problems. • Manage expectations. • Be patient and persistent. • Decide what really bothers you.
• Use adaptive management and long-term thinking.
The newest secret weapon in the war, according to Morse?
“Goats!” said Morse, showing a slide and drawing a laugh. In fact, he’s experimenting with using goats in prescribed grazing to help control non-native invasives.
Morse recommends www.invasive.org as a resource for information on invasive plants and insects.
The tour of the butterfly trail project on the cool, drippy morning gave attendees an up-close look at the newly planted host and nectar plants used to draw butterflies in the gardens near Avon Hall. The master naturalists guides described plans for careful removal of invasives to make way for natives.
Price, a certified Virginia master naturalist and president of the Shenandoah National Park Association, said many invasives have names starting with “Japanese” or “Chinese” because they come from the same latitudes as our region. “These conditions are just what they’re used to.”
His answer? “You can do a lot of hand work, you can use Roundup to spray. But you’re not gonna eliminate invasives. The best you can hope for is control.”
The workshop was the third in RLEP’s education series this year. Previous workshops featured naturalist Bruce Jones and a presentation on ticks and Lyme disease. This fall, RLEP plans a program on bears.
Larry “Bud” Meyer is an RLEP board member.
From left: Jack Price, Brian Morse, Jenny Fitzhugh and Bryan Lilly presented most of the information at the RLEP invasive plants workshop. Sam Quinn, right, is the biologist at the Farm at Sunnyside and the RLEP board member who helped organize the...