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?

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
Not Yet Rated

Saturday - June 12, 2010

From: North Liberty, IA
Region: Midwest
Topic: Diseases and Disorders, Trees
Title: Leaf problems on oaks in North Liberty IA
Answered by: Barbara Medford

QUESTION:

My oak trees (young and old) are showing leaf problems. Is there a disease or insect causing oak tree disease?

ANSWER:

There are whole books written on pests and diseases of oak trees. In our Native Plant Database there are 78 species of the genus Quercus (oak) native to North America, 14 native to Iowa. In Johnson Co., Iowa you are in USDA Hardiness Zone 4b to 5a. Some of the oaks that are native to Iowa would burn up in Texas, and the Texas oaks would likely have freeze damage in Iowa. Without information on what oak, how old it is, what the leaf symptoms are and how long it has been going on, we couldn't even begin to guess. When we googled "pests and diseases of oak trees," we got a lot of results. We are going to send you links to a few of them so you can look at pictures and read descriptions, which might at least give you a start on identifying problems and treatments, if any. The best and most accurate help can come from the Iowa State University Extension Office for Johnson County. Whatever the problem is, it probably won't be the first time they have heard of it, and they may even have printed materials on what to do.

treehelp.com Oak Trees

USDA Forest Service Sudden Oak Death

gardenguides.com Pests and Diseases of Oak Trees

We are going to give you a list of members of the Quercus  genus native to Iowa, and pictures of some of them.  This doesn't necessarily include the trees you have; there are hybrids, the trees sometimes do their own cross-breeding, and you may have trees from another area. 

Members of Quercus Genus Native to Iowa:

Quercus alba (white oak)

Quercus bicolor (swamp white oak) - pictures

Quercus ellipsoidalis (northern pin oak) - pictures

Quercus imbricaria (shingle oak) - photos and more information

Quercus macrocarpa (bur oak)

Quercus marilandica (blackjack oak)

Quercus muehlenbergii (chinkapin oak)

Quercus palustris (pin oak) - photos and more information

Quercus prinoides (dwarf chinkapin oak) - photos and more information

Quercus rubra (northern red oak)

Quercus rubra var. ambigua (northern red oak)

Quercus rubra var. rubra (northern red oak) - photos

Quercus stellata (post oak)

Quercus velutina (black oak)

From our Native Plant Database:


Quercus alba

Quercus macrocarpa

Quercus marilandica

Quercus muehlenbergii

Quercus rubra

Quercus rubra var. ambigua

Quercus stellata

Quercus velutina

 

 

 

More Diseases and Disorders Questions

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

Tulip trees losing bark in OH
July 11, 2011 - We have two tulip trees in our yard that are losing their bark at the base of the trunk. I am careful with the mower keeping away from the tree when I mow. What could the problem be and what can I d...
view the full question and answer

Grey Goo Coming from red Oak in Manchaca TX
May 13, 2013 - I have a large Red Oak in my yard that appears to be weeping some sort of grey goo from parts of the trunk. What is this goo and do I need to treat it and if so how? I'm happy to come by the Wildflow...
view the full question and answer

Prickly pear doing poorly on Long Island NY
December 27, 2012 - First, thanks for your reply on 11-3-12, re.Can a prickly pear cutting from Harker Heights, TX find happiness in Long Island, NY. The plants were set before a southern window in the attic, temp. ra...
view the full question and answer

Hibiscus wilt in Texas Star hibiscus
November 10, 2005 - I have a Texas star hibiscus on my deck. It flourished all summer, but not quite a month ago, the leaves turned yellow and fell off. Will it come back? What happened???
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center