If you employ the basal bark method, you can effectively control Ailanthus altissima — tree of heaven — this month. See Blue Ridge PRISM Invasive Plant ID & Control App/Tree-of-heaven. Tree of Heaven (Ailanthus altissima) is a dreaded nonnative invasive that threatens natural areas, agricultural fields, disturbed areas, and back yards. To top it off, this invader attracts and provides a home for the nonnative insect pest, Spotted Lanternfly, which prefers, and may even require, Ailanthus altissima trees to complete its lifecycle. Be aware that tree-of-heaven — with its compound leaves — resembles some of our beloved native trees, including sumac, black walnut, and hickory. This video can help you with a positive identification: www.youtube.com/University of Maryland Extension Home and Garden Information Center.
For trees with trunks 4 to 6 inches in diameter, a basal bark treatment with an herbicide is effective from late winter until early spring. See the Blue Ridge PRISM (Partnership for Regional Invasive Species Management) Factsheet for information on how to identify and eradicate this invasive.
Here’s the basic how-to for basal bark treatment:
“For trees with trunks 4 to 6 inches in diameter, instead of a foliar spray, use a basal bark treatment from July to the onset of fall color in very late summer, when the tree is moving carbohydrates to the roots. Alternatively, you can apply it from late winter to early spring when there is less vegetation. Spray a complete circle of a concentrated, recommended herbicide diluted in an oil-based carrier on the lowest 12 inches of the trunk.”
– Blue Ridge PRISM/Fact Sheet/Tree-of-Heaven
For detailed videos to guide you in using the basal bark method — as well as other methods — check out the new videos put together by Dr. Stephen Enloe of the University of Florida at:
Winter control measures — cut-stump, basal bark, and hack-and-squirt — are also effective on shrub honeysuckles (Lonicera spp.), autumn olive (Elaeagnus umbellata), multiflora rose (Rosa multiflora), and Japanese barberry (Berberis thunbergii). See ‘Tis the Season — Winter Invasive Plant Control/ Penn.State.
Featured Photo: Ailanthus altissima by Richard Gardner, Bugwood.org