Rent Shop Volunteer Join

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
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

Thorny plant for fenceline security
December 23, 2009 - What kind of thorny plant or vine would you suggest to place along a fence for security purposes
view the full question and answer

Spacing for Dogwoods and Cotoneasters
February 21, 2016 - How close should Dogwoods and Cotoneasters be to bricks?
view the full question and answer

Need for sunlight for Sophora secundiflora to bloom
June 22, 2007 - My mountain laurel doesn't bloom. We live in Oak Hill and planted it about seven years ago. It bloomed one year at about age three or four. Since then nothing. What can I do? It only gets indire...
view the full question and answer

Problem with Prosopis glandulosa (Honey mesquite)
February 27, 2014 - One of our mature Honey Mesquite trees is losing thumb sized branches high up in the canopy because something is stripping the bark. The branches are completely white for 8-12 inches. Of course the ...
view the full question and answer

Changing colors on Mexican Plum trees from Bellaire TX
June 20, 2013 - The leaves on my Mexican Plum tree have recently started turning yellow/brown and the veins in leaves are red. Is this a watering issue or disease issue? Mites are on the leaves. This has been a ra...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.