Viburnum leaf beetle could be the next nuisance insect in the same vain as Japanese beetles. One of the most popular and easiest to grown shrubs is the Arrowwood Viburnum (Viburnum dentatum), which means it’s fairly easy to find one in almost every landscape. The Viburnum leaf beetle larvae and adults will feast on the foliage of Viburnums; quickly defoliating it. After several years of defoliation your viburnum can die. The adult beetle will then lay it’s eggs on the stems to make it an easy perennial pest, year after year!
What to look for and how to get rid of this pesky pest!
Once viburnums have dropped their leaves in fall, look for egg masses along the undersides of the twigs. Prune out and discard any damaged branches or twigs. Do not compost this debris for mulch.
In late spring and early summer, look for small holes that skeletonize the leaves between the veins. On the underside of the leaves, you might see tiny, yellow-brown caterpillars, some with spots. Destroy any damaged leaves that drop.
A few weeks after hatching, the larvae drop to the ground and burrow into the soil to pupate. In about six weeks, the adult beetles emerge, feed on the leaves and lay eggs to start the cycle all over again. The 1/4- to 3/8-inch long, golden-brown beetles look shiny in the sun.
Highly susceptible:
V. dentatum: Arrowwood viburnums
V. nudum: Possum-haw, smooth witherod viburnum
V. opulus: European cranberrybush viburnum
V. opulus var. americana (syn. V. trilobum): American cranberrybush viburnum
Susceptible:
V. acerifolium: Mapleleaf viburnum
V. lantana: Wayfaring tree, Mohican viburnum
V. sargentii: Sargent viburnum
Moderately susceptible:
V. burkwoodii: Burkwood viburnum
V. carlcephalum: Carlcephalum viburnum
V. cassinoides: Witherod viburnum
V. lentago: Nannyberry viburnum
V. prunifolium: Black-haw viburnum
V. rhytidophylloides: Lantanaphyllum viburnum
Most resistant:
V. carlesii: Koreanspice viburnum
V. juddii: Judd viburnum
V. plicatum and V. plicatum var. tomentosu: Doublefile viburnum
V. rhytidophyllum: Leatherleaf viburnum
V. sieboldii: Siebold viburnum
Not sure what to do, then contact one of our professional horticulturists to help assess the problem.