En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
Not Yet Rated

Sunday - August 23, 2009

From: Savage, MN
Region: Midwest
Topic: Diseases and Disorders
Title: Failure to thrive of trees in Savage MN
Answered by: Barbara Medford

QUESTION:

I have a 20+ year old weeping willow. The last few years it is the last tree to get its leaves and the first to lose them. The few leaves that are still on the tree are covered with brown/black spots. I also have a 20+ year old Marshall's Seedless Ash in a different area. It's lost most of the leaves from the center of the tree. Many of the leaves that remain have some yellow to brown spots in the center and/or are brown at the edges. Any suggestions? Thank you.

ANSWER:

Thank you for your question. While we would like to answer all questions we receive, Mr. Smarty Plants' expertise is limited to plant species native to North America, their habitats and cultivation. Limited resources require us to decline answering questions that delve into other areas. We hope you understand.

Non-native to the United States, Salix x sepulcralis is a hybrid of a Chinese species (Peking willow) and a European species (white willow), and is said to grow in Zones 5 to 8 in the United States. We are astounded that it has lived as long as it has, since you are in Zone 4a, with average annual minimum temperatures of -30 to -25 deg. F. It is weak-wooded, fast-growing and, therefore, short-lived. It has aggressive roots, can lift sidewalks and interfere with sewer lines, often growing on soil surface, making a problem with mowing. It is susceptible to a number of pests and diseases, and notorious for littering the ground beneath it. You might check out this University of Florida Extension website on Weeping Willows for more information as well as this Q&A from North Dakota State University Extension on weeping willows.The UBC Botanical Garden Forum is also a good source of information on non-native plants. 

Fraxinus pennsylvanica (green ash) has been given the trade name which is discussed in this USDA Forest Service 'Marshall's Seedless' Green Ash.  It is hardy in Zones 3 to 8a, and native in and around Scott County in Minnesota, so it belongs there. However, like the weeping willow, it is fast growing, has roots which can disrupt foundations and sidewalks, and is short-lived. In fact, the USDA article mentioned above "no longer recommends this tree due to weak branch crotches, insect problems and fruit set." Since we are not plant pathologists and couldn't hope to diagnose or recommend treatment at this distance, we suggest you contact the University of Minnesota Extension Office for Scott County. They may recommend you have it looked at by a trained and licensed arborist, if you feel the tree is worth saving. 

From the Native Plant Image Gallery:


Fraxinus pennsylvanica

Fraxinus pennsylvanica

Fraxinus pennsylvanica

Fraxinus pennsylvanica

 

 

More Diseases and Disorders Questions

Growth on top of Echinacea purpurea (Eastern purple coneflower)
July 03, 2012 - I grow purple coneflowers in my garden. ONE plant has something growing on the top of each cone. I would like to know what it is but I don't see how I can add a photo to this post.
view the full question and answer

Brown patches on St. Augustine grass
April 24, 2009 - I have brown patches on my st. augustine grass, it looks like the grass has rotted from standing water, but the drainage is not a problem, What could it be?
view the full question and answer

Freeze-damaged Texas Mountain Laurel in Austin, TX.
May 05, 2011 - I have a Texas Mountain Laurel (Sophora secundiflora) that is several years old. During this past winter, one of the freezes we had split one of the largest trunk right below the soil line. T...
view the full question and answer

Leaves dropping on evergreen sumac in San Antonio
January 11, 2012 - I have a large evergreen sumac in my back yard that started off as a small shrub 10 years ago. This summer the leaves turned red and now have dropped off. Is the plant dead? It sent out two smaller pl...
view the full question and answer

Non-native Chamaecyparis pisiflora turning brown in Fuqua-Varina NC
December 10, 2012 - I have a "Soft Serve False Cypress" Chamaecyparis pisifera'Dow Whiting PPAF, that has only been in the ground for 6-7 months. I just noticed that the branches and leaves are starting to die, turni...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center