Warty Tomatoes, A Darkling Beetle & more Lichens

tomato plantjpg

A tomato, a Mountain Magic hybrid, with stem warts. Photo: Gretchell Rogers

Ms. Gretchell sent several pictures of a tomato plant, a Mountain Magic hybrid, with a warty stem. She also submitted a plant to the Plant Diagnostic Lab in Baton Rouge for a diagnosis.

These warts are the beginning of root hairs called “adventitious roots”. According to the Mississippi Extension, “Adventitious roots are almost always a sign of some type of stress including high humidity environments, over watering or poor drainage, root damage, herbicide damage, and disease problems.” A diagnosis from the Plant Diagnostic Lab may help identify the stress causing the warts on this stem.


A darkling beetle is a harmless insect. Photo: George Giltner

Ms. Loretha brought in an insect from her home and wanted to know if it is harmful.

A close-up image of this insect went to the Louisiana State Arthropod Museum for identification. A specialist identified this insect as a darkling beetle, and are not considered pests. It is harmless to humans.

fruticose lichensjpg

"Reindeer" or fruticose lichens.

Mr. Jeremy brought in some samples to an AgCenter office and wanted to know "what is killing his pecan and oak trees and how to stop it.”

foliose lichensjpg

Scaly or foliose lichens.

These are two types of lichens shown in the images. Dr. Raj Singh writes, “They are composed of two different organisms – a fungal partner and a photosynthetic partner living in a [beneficial] relationship. The photosynthetic partner is either a green alga or a blue-green bacterium. Lichens get their nutrients from the food prepared by the photosynthetic partner, and the fungal partner provides the body and shape.”

Lichens are more of a symptom than a cause with regards to Mr. Jeremy’s trees. Lichens are taking advantage of more light due to a thin canopy of leaves. Something else is stressing the oak and pecan trees.

If you want to contact Roots, Shoots, Fruits and Flowers, please send your questions and pictures to Keith Hawkins, Area Horticulture Agent (AHA), 337-463-7006 or khawkins@agcenter.lsu.edu. Also, you can be on the “green thumbs” email list by emailing your request to the address above.

“This work has been supported, in part, by the USDA National Institute of Food and Agriculture, Renewable Resources Extension Act Award, Accession Number 1011417.”

7/2/2019 6:16:07 PM
Rate This Article:

Have a question or comment about the information on this page?

Innovate . Educate . Improve Lives

The LSU AgCenter and the LSU College of Agriculture