Rent Shop Volunteer Join

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?

Share

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
1 rating

Friday - May 07, 2010

From: Austin, TX
Region: Southwest
Topic: Pests, Trees
Title: Problems with rusty blackhaw viburnum in Austin
Answered by: Barbara Medford

QUESTION:

I have a four foot rusty blackhaw viburnum. Last summer the leaves turned reddish and in the late summer most of them fell off. This February the plant started to leaf out and then bloomed. It has three trunks. One trunk had big blooms, the other two had small blooms. After the blooms died out, the trunk with the big blooms leafed out like it should with big leaves. The other trunks just have tiny leaves. What's happening?

ANSWER:

According to this USDA Plant Profile, Viburnum rufidulum (rusty blackhaw) grows natively in Travis County, so you have the right plant in the right place. An article from Floridata on Blackhaw Viburnum includes this information:

"Rusty black-haw is really a small tree rather than a shrub because it usually grows with a single trunk. It has a slender trunk, an open, irregular or rounded crown, and starts branching close to the ground."

This article goes on to say that sometimes it will put out suckers from roots and can even develop into a thicket. Perhaps the smaller stems are really suckers and that is why that area is not developing as well. You can choose to trim off those suckers and make your viburnum a single-leader tree, the way it is apparently meant to be, but we don't think there is any harm in them. 

Returning to the falling of the leaves last summer, we all remember what a very difficult summer last year's was, with extreme heat and drought and watering restrictions. The fact that the main leader of your plant has bloomed and put out leaves normally leads us to believe that it was just reacting to environmental stresses. Here are the Growing Conditions for this plant from our Native Plant Database:

"Water Use: Low
Light Requirement: Part Shade
Soil Moisture: Dry
Cold Tolerant: yes
Soil Description: Dry soils. Limestone-based, Sandy, Sandy Loam, Medium Loam, Clay Loam, Clay
Conditions Comments: Slow-growing. Hard to propagate. With its waxy leaves, rusty blackhaw presents excellent fall hues of red, lavender, pink, and orange. Tiny clusters of flowers bloom in spring. In Manual of the Vascular Plants of Texas, Correll and Johnston noted that the fruit tastes similar to raisins. Rusty blackhaw is good for understory plantings. Birds appreciate the fruit."

As well as we can determine, this is a native tree surviving in its own way, and doing okay at it.  You might also read this USDA Forest Service article Viburnum rufidulum. Toward the end of that article, it details some pests and diseases of this plant that you should look out for. 

From our Native Plant Image Gallery:


Viburnum rufidulum



Viburnum rufidulum

Viburnum rufidulum

 

 

More Pests Questions

Plants ants avoid from McAllen TX
May 22, 2010 - Which native plants do ANTS avoid (are there?)? We have a big ant problem here. Thanks!
view the full question and answer

Loss of leaves from globe willows in Utah
July 26, 2008 - I have four globe willows that have been in my back yard for the past 6 years. For the past month they have been losing their leaves from the bottom up. We had aphids in some of our other trees and ...
view the full question and answer

Varmints disturbing plants in NH
August 04, 2011 - I planted herbs and perennials, then put paper down and bark. At first an animal just disturbed the paper around the plants, exposing it. Today two plants are dug up and are completely gone. No sig...
view the full question and answer

Grasshopper invasion in Box Elder SD
August 22, 2011 - I just bought a new home and there is an infestation of grasshoppers throughout the neighborhood. What shrubs and/or flowers could I plant that they may not like to eat?
view the full question and answer

Possible maple scale on non-native mophead hydrangeas from Newport RI
August 07, 2013 - I have a mophead hydrangea that has small white cottony tufts under the leaves and on the stems. I believe this is maple scale. Is there a home remedy I can use to rid this disease?
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.