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
1 rating

Friday - June 11, 2010

From: Huntsville, TX
Region: Southwest
Topic: Trees
Title: Pecan with brown spots on the leaves
Answered by: Nan Hampton

QUESTION:

Southern pecan, I am a 8 foot tall and 3 year old (young)tree. My leafs have brown spots on top and hard shell mound on the bottom, this is on about 3/4 of the of the leafs, could you tell me what this is and how to fix it? Thank You.

ANSWER:

Mr. Smarty Plants is very sorry you are ailing.  I would like to compliment you on your communication skills, however!

I consulted several sites that had information on diseases and pests of pecans.  University of Missouri Extension's Pecan Pest Management: Insects and Diseases, University of Arkansas Cooperative Extension's Home Pecan Diseases and Control, Louisiana State University's Agricultural Center's Pecan Disease Synopsis, Clemson University Cooperative Extension's Pecan Diseases, and Texas A&M University Cooperative Extension's Pecan Kernel Diseases.

Your symptoms didn't sound exactly like any of the ones listed, but here are the diseases or pests with  symptoms that most closely resembled yours: 

1) Downy spot fungus caused by Mycosphaerella caryigena

2) Pecan Phylloxera caused by the insect, Phylloxera devastratrix

3) Zonate leaf spot caused by the fungus, Cristulariella moricola

4) Brown leaf spot caused by the fungus, Cercospora fusca

Most of the descriptions of the above conditions offer recommended control measures.

You can also read a rundown of pests and diseases affecting Carya illinoinensis (pecan) from the U. S. Forest Service.

Since pecans are considered agricultural crops you might like to visit Texas AgriLife Extension "Ask an Expert" to ask them the same question.  They are likely to have a plant disease expert on hand who knows pecan tree diseases better than we do.

 

More Trees Questions

Problems with mature cottonwood in Justin TX
September 17, 2012 - I have a very large, 90" circumference, approx 60' tall, cottonwood tree in my front yard that appears to be sick. The trunk splits at about the 4' level into 2 parts. at that split is a 10" wide...
view the full question and answer

Privacy Screening Plant for New York Narrow Site
April 20, 2013 - I need privacy screening on the side of my house in Mount Kisco, New York located 40 miles north of New York City. The area gets plenty of sun but is somewhat narrow. What evergreen bushes or trees ...
view the full question and answer

Mixed native plantings for steep slope in Austin
April 18, 2007 - Dear Mr. Smarty Plants: We wrote to you recently about plantings for a fairly steep slope in a park in Austin. We had asked about grasses and perennials. An article about planting on slopes in this mo...
view the full question and answer

Rhododendrons for afternoon sun
September 10, 2008 - Thanks for your suggestion that I plant rhodedenrons in my Brooklyn garden. In fact, the only bushes I've planted in the past that have survived are rhodedenrons so your definitely right! Here's my...
view the full question and answer

Surface tree roots hurting grass in Houston
March 21, 2013 - We have 2 mature Arizona Ash trees in our yard (30-40'). One of them is in a sunnier location and has developed an extensive network of surface roots (up to 1 to 1 1/2" Dia.) between the tree and th...
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