En Español

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

Sunday - September 25, 2011

From: Washington, PA
Region: Mid-Atlantic
Topic: Non-Natives, Diseases and Disorders, Pests, Trees
Title: Swarming insects on non-native willow in Washington PA
Answered by: Barbara Medford


I have had a very large, beautiful pillow willow bush/tree growing next to our garage for about 8 years. Last year at the end of August, it began to attract white-faced hornets and yellow jackets by the hundreds, which I wrote off as a passing swarm once the weather cooled. However, the same thing happened again this year and I feel, with small children and dogs, we have a problem that needs addressed for safety reasons. Right now, there are thousands of both white and yellow "stingers" focused on the base of the tree. I cannot get very close to the tree, but have noticed a layer of small, black, rice-sized bugs covering sections of the far reaching branches. The trunk of the tree also looks like it has been splashed with black stain. Is the tree too far gone? Should I rip it out and start again by rooting some clippings or will the problem transfer? It hangs out over a grape trellis so I have hesitated to use poison.


Okay, we give up. Our research did not turn up any plant called a "pillow willow." We can pass on to you, if you wish, the websites where you can order a pillow with a picture of a willow on it. So, with your permission, we will address the problem of the generic willow tree.

The thing is, we're not crazy about willows, regardless of their name. There are members of the Salix (willow) family native to North America. They are not, generally speaking, considered landscape plants, but mostly occupy wetlands in their native areas. From the webpage on Salix bebbiana (Bebb willow), which is native to North American, here are the Conditions Comments:

"Short-lived and fast-growing. Susceptible to insect, disease, and wind damage."

This basically sums it up for willows, wherever they come from. Here are links to some previous answers on this subject, so we don't repeat ourselves:

From Cumbola, PA

Disease in non-native willow

We searched the Internet on "hornets and yellow jackets in willows" and found this article A Yellow Jacket Infestation in Willow Trees. Then, we looked at "Pests and Diseases of Willow Trees." From one of our favorite sources for horticulture information, North Dakota State University, we found Questions on Willows.

Now to cut to the chase. We think the tree needs to go. Obviously, you need to wait until the stingers have gone away for the winter, and even then, it would probably be better to have a professional arborist remove it and as much of the roots as possible. Then, during the winter, go to our Native Plant Database, click on Pennsylvania, and search on "tree" under General Appearance. You can also, in the same Combination Search, specify the amount of light the growing space has, how moist the soil, even desired height of the tree. We don't recommend taking cuttings to replace it, but to find a better-adapted healthy tree, native to your area-one that has a long lifespan ahead of it, and is less likely to develop diseases that will cause the sort of problem you are having now. Be happy with a willow pillow and forget the pillow willow-you'll be better off in the long run.


More Non-Natives Questions

Fertilizer burns on non-native St. Augustine grass
September 07, 2009 - We put summer guard fertilizer on our lush St. Augustine grass and it didn't get watered in after application. As a result we have burned the yard badly in patches. What can we do to correct proble...
view the full question and answer

Freeze damage to non-native Sago Palms in Austin
May 03, 2010 - Due to the unusually cold winter in Austin my sago palms fronds froze. I have not removed the dead fronds should I? If only the fronds froze when will new fronds start to grow?
view the full question and answer

Bugs on non-native Pachystachys lutea in Hawaii
August 20, 2009 - My golden shrimp/lollipop plant has aphid like bugs. They are darker and firmer than aphids but clump like them. They are consuming it. What are they and how do I get rid of them?
view the full question and answer

Can Allamanda cathartica be used as an insecticide
October 31, 2008 - is allamanda cathartica can be used as an insecticides?
view the full question and answer

Native plants for southwest exposure in Tulsa OK
April 24, 2008 - I want to plant something in a bed on the South side of my house with some Western exposure. The space is in a bed that would share space with a Red Tip Photinia (next to the house)& liriope( on the ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2016 Lady Bird Johnson Wildflower Center