Japanese Honeysuckle Reminder
This is the ideal time of year to combat invasive Japanese Honeysuckle, an aggressive shrub that takes over and smothers everything in its path. Woods and stream banks in southern Ohio are being taken over, the bright red berries spread everywhere by birds. After first frost it’s easy to spot huge, spreading “mother plants” covered with berries, a carpet of seedlings under them where their berries have fallen.
If you own wooded acreage, this invasion is likely well advanced on your property. You need to take action before your entire landscape turns into a jungle. In doing so you’ll contribute to one of the most important environmental battles of our time. Any urban forester, forest ranger, park manager or conservationist is probably losing sleep over this problem right now. We have 180 acres, much of it being invaded by Japanese Honeysuckle. Over the past few years we’ve tried many different methods of beating back this scourge.
The key to success is timing. Japanese honeysuckle is one of the last woody plants to go dormant and drop its leaves in fall. Amur honeysuckle bushes plants really stand out right now, with glowing neon green foliage and shiny red berries. Because most other woodland plants have lost their leaves, we have a two-week window in early November when we can spray glyphosate on the invaders with little or no damage to other plants.
Small infestations can be treated with an inexpensive pump sprayer. For larger properties, a backyard fogger is much more efficient. We have many acres to deal with, so our weapon of mass destruction is our Stihl backpack fogger. Similar to a backpack leaf blower, this dandy machine has a 2-1/2 gallon tank and an injector nozzle that mixes glyphosate with a powerful blast of air, creating a fog that can reach plants 15 feet tall and over 30 feet away. The air blast ruffles the leaves, thoroughly coating both the top and underside of the leaf with a fine mist.
We can unleash a glyphosate fog into dense honeysuckle thickets, the wind at our back, hitting the tops of the tallest plants while dousing the carpet of seedlings underneath, as fast as we can walk, covering many acres along hedgerows and hillsides in a single afternoon. Hiking with the backpack sprayer is a workout, but so much faster and easier than any other method we’ve tried by far.
Starting with easily available 41% glyphosate (Roundup) concentrate, we simply measure two cups (16 ounces) into the sprayer tank and top it off with water. Setting the injector nozzle on 2 seems to give just the right amount of coverage. It takes about fifteen minutes per tankful to empty the tank, at a brisk walk.
A key strategy is to focus on the big, established “mother plants” first, because Japanese honeysuckle can’t reproduce until the plants mature and start to have berries. Birds, attracted by the shiny red berries, spread the invader far and wide. Berries drop under the mature plants and create a carpet of seedlings. An online search turned up no evidence that eating glyphosate-treated berries is harmful to birds.
Armed with our newfound “weapon of mass destruction”, we’ll take up the battle again in the coming weeks. I urge you to join it, in your own yard. Timing is everything. Seize this opportunity to turn the tide of the honeysuckle invasion.
Steve Boehme is a landscape designer/installer specializing in landscape “makeovers”. “Let’s Grow” is published weekly; column archives are on the “Garden Advice” page atwww.goodseedfarm.com. For more information is available atwww.goodseedfarm.comor call GoodSeed Farm Landscapes at (937) 587-7021.