Holes

Holes

I was folding my lace tablecloth that I air-dried outside after washing out a stain as a result of coffee spilled during a weekend get together. And as I was bringing two ends of the fabric neatly together, the sun shone through my back patio doors and beamed through the holes in the lace.

If you've ever seen these neat pinpoints of light come through the intricate shaped holes in this delicate fabric, then you have an idea what viburnum leaf beetle damage looks like on the shrub's velvety emerald leaves. The reason it's on my mind lately is because the pest is particularly bad this year, according to Greg Mazur, one of our many arboricultural gurus (or officially, technical service advisors) at The Davey Institute.

The term used to describe this damage done by the beetle larvae in spring is skeletonized. Then irregular holes are chewed into the leaves by the beetle adults in summer. Unfortunately, branch dieback follows the rapid defoliation. In one to three years, viburnums are toast.

And Mazur now realizes he was being generous when he gave viburnums one to three years against this pest. For he knows all too well the swift damage they cause.

He knew the beetle was coming. It is an invasive species that came from Europe to North America in the 1940s and then into the U.S. in the mid-1990s. Mazur has native viburnum growing in the woods behind his home. In 2008, as he was mowing the lawn and spreading the grass clippings in the woods, he noticed the viburnums were being nibbled on. "But I didn't think too much of it," he says. "I thought I'd get around to spraying them later in the summer."

Then by the end of summer, every leaf on every viburnum was skeletonized. "The viburnum stuck out because they were all bare twigs," he says. "So I said, 'I blew my chance but I'll get them next year.'"

But in the spring of 2009, the viburnum didn't even leaf out. Mazur's only leftover option was to get out a pair of loppers and cut them down.

And our expert scientist isn't alone. He remembers a Davey client calling last year. "She said her viburnums looked OK on Monday," he says. "But by the Friday before Memorial Day - five days later - they were nearly dead."

VLB3

How can the beetle cause such swift destruction? "Because there are no natural predators, viruses or bacteria in U.S. to slow down this introduced species," Mazur explains.

The pest is moving throughout the U.S. rapidly. "It's like when you throw a stone in a pond and the ripples move outward from the point of impact," Mazur says. "The beetle will continue to spread as long as there are viburnums in its path."

Though scientists are still trying to understand the true extent of this species, they are getting good control of the pest in mid-May with an insecticide application. Then when the adults emerge, a follow-up application can prevent them from laying eggs on the branches. As always, strong cultural practices are important, and your professional arborist can take good care of your shrubs with proper irrigation, mulching and fertilization to keep them strong enough to resist the beetle.

Holes in your viburnums? Call your local arborist today to save your plants. There's no second chance with this pest. "If you do nothing this year, you might not have to worry about it," Mazur says, chuckling softly remembering his own backyard, "because you may not have any viburnums left."

"Think you're a big fan of trees? We'd love to hear about it. Send your thoughts to Dave or Daphne at blog@davey.com ."

Add a comment:
Featured or Related Blog Posts
  • Root in Moisture

    Planting trees is just half the battle.

    The diseases, pests and power equipment that emerge outdoors in spring, accompanying frequent sunlight, longer days and warmer temperatures, can wreak havoc on your trees if you don't put forth the effort to protect them.

    To keep your trees healthy throughout the growing season and beyond, you must practice routine maintenance and proper tree care. One way to help trees retain moisture, reduce weeds and keep power equipment at a safe distance is through mulch. In the coming weeks, you'll see piles of fresh mulch lined along neighborhood driveways. Soon, the coarse, fragrant matter will settle among flower and tree beds, enhancing the quality of landscapes' appearances.

    Read More
  • Just a Trim, Please

    Put a pair of scissors in your hands, and whether you're cutting coupons or bangs, there's always the potential to oversnip. It's almost too easy to make a mistake as you clip, clip, clip away - removing a little more on this side and a bit more on that side.

    Just like with a bad haircut, there is nothing more noticeable than a poorly pruned plant - pieces sticking out in all directions, a butchered shrub, a tree that looks like the top has been sliced off. The good news is that just as the perfect haircut can frame the face and improve a person's appearance, the same can be said for a professional tree pruning job.

    Pruning is not only a science, but an art form. The science aspect of pruning involves understanding tree biology, recognizing plant flaws and skillfully eliminating or minimizing defects. The artistic aspect of pruning consists of removing dead wood while aesthetically shaping the tree.

    Read More
  • Heat Wave

    Heat wave.

    The term usually makes many people think of the tropics or the desert.

    But extreme heat has hit many areas hard so far this summer. Record highs have been broken in some cities, while others have seen their hottest temperatures since the 1980s.

    Read More
  • Forecast: Hot & Humid

    The air-conditioning is set on high. The fan is blowing in my face. And it feels so good, particularly since my dog and I were just panting within seconds of stepping out to a heavy wall of heat and humidity. His face tilts up to mine, happy for the nice, cool breeze. We face the facts together as I sip from a tall, cool glass of water and he laps up the same out of his bowl: Despite our yearning to enjoy the outdoors, it's hot. And it's hot in nearly every region of the country.

    There's simply no denying it: This summer's a scorcher. While it's difficult to find the motivation to open the door to the heat lingering in the air outside - let alone step out onto a dry, parched lawn - I brave the elements because I notice my trees need some TLC, too.

    It's difficult to imagine another day of 90-plus degree temperatures. So I can hardly imagine how my trees must feel as their roots cling to nothing but the dry soil, day after day.

    Read More
  • Try a Little Tenderness

    When someone moves into a new home, they tend to have a smoother, more successful transition when they plan ahead and carefully move through each step. This includes thoughtfully packing boxes beforehand in an organized fashion, clearly labeling the boxes so movers put them in their proper rooms and then unpacking them so everything that is removed is unwrapped and put into its place to avoid rework.

    If this works for your most delicate China place settings and Lenox crystal, you can see why it would make all the difference when moving something as large, yet just as delicate, as a tree.

    When it's a big, valuable tree that provides numerous benefits to your landscape and your family, a "move" is much more than just picking it up and placing it in its new location. To preserve the numerous benefits trees provide to a community and its residents, which The National Tree Benefits Calculator can help determine, one must plan carefully - before, during and after the big move - to ensure survival.

    Read More

Request a consultation

What do you need services for?
Sorry, we can’t seem to find the zip code you specified. Our residential tree care offices may not service your area. If you believe this is an error, please try again. Need help? Email us at info@davey.com.
  • Email newsletter
  • Woodchips
*Please fill out all required fields.