Explore Plants

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
    
 

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

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

Smarty Plants on Ebenopsis
July 01, 2005 - Why is the Texas Ebony, genus Pithecolobium, not in your database? Is it not a native? Thanks.
view the full question and answer

Seed germination for sugar maple (Acer saccharum)
December 15, 2007 - How can I germinate sugar maple?(step by step, please) I have some seeds but can't make them grow directly outside, so could you recommend a method which takes place inside?! I've heard something ab...
view the full question and answer

Possible wilt disease in mountain laurels
August 31, 2006 - Three of about 24 of my mature mountain laurels died suddenly, the leaves turned brown almost overnight, scratching the bark revealed no green tissue, the small branches practically cracked when bent,...
view the full question and answer

Distinguishing elm species from volunteers in yard
April 10, 2008 - What's the best way to distinguish young elm tree species apart from one another? We have a bunch coming up in our yard and we're trying to figure out if they are Winged, Cedar or American. Some of ...
view the full question and answer

Bark flaking off oaks in New Braunfels, TX
April 12, 2010 - We have several large clusters of oak trees. Some of the trees are losing their bark. The bark is flaking off in fairly large pieces; even on some of the trees that are leafing out. Is this a result o...
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.