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

Salvia, geum transplant shock symptoms
July 21, 2006 - I need some help. I transplanted 2 xeriscape plants and they are not doing well. 1 is Pitcher Sage-sorry I don't know botanical name; the other is White Avens. The've grown a lot but all the leave...
view the full question and answer

Is December a good time to prune oaks in Central Texas?
December 29, 2010 - Given that we haven't had much cold weather here in central Texas (Wimberley) this season, is it a good time to trim live and Spanish oak trees (damaged limbs and low hanging branches and suckers)? ...
view the full question and answer

Rust problems on Jack in the Pulpit in IL
June 12, 2011 - The last 2 years I have noticed that some of my jack in the pulpit plants have something that makes me think of a copper color rust.It seems to start on the underside of the leaves. What can I do to g...
view the full question and answer

Sap oozing from non-native Chinese pistache in San Antonio
September 07, 2011 - I live in San Antonio, and my chinese pistache is exuding copious amounts of a sticky sap from old trim sites and from the trunk itself. The tree is about 12 years old and has been healthy up until no...
view the full question and answer

Problems with Eves necklacepods (Styphnolobium affine)
March 25, 2008 - Mr. S-P, I urgently need your advice regarding two Eve's necklacepods that appear to be dying. They are in two completely different areas of my yard. One began leafing out and then the leaves sh...
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