Non-Venomous Snakes, Convict Caterpillars, Laurel Wilt & Tomato Aphids

a non venomous king snake killing a copperhead, a venomous snake
Non-venomous king snake killing a copperhead, a venomous snake.

Lisa shared this image of two snakes and wanted gardeners to be aware of an important difference in snakes.

Even though many people are taught to automatically to kill all snakes, keep in mind that non-venomous snakes control venomous snakes and also rodents. Try to exercise self-control and determine if a snake is venomous or not.

convict caterpillar

Convict caterpillar before it becomes a spanish moth.

Linda sent a picture of a caterpillar on Louisiana irises and wanted to know the name of this caterpillar.

If you guessed a name pertaining to criminal justice, then you would be very close. This pest is called a “convict” caterpillar, and it grows up to be a Spanish moth. The Spanish moth is native to both North and South America and it prefers to feed on plants in the amaryllis, iris and lily families. Products like Dipel® or Thuricide® are labeled to treat “worms” with a pathogen that will only infect caterpillars.

ambrosia beetle infested tree

Ambrosia beetles.
Photo: Alabama Forestry Commission.

Gary came by the AgCenter to share an observation; the sassafras tree in his yard is turning brown and leaves are falling off. He is also noticing this [pattern] happening around Merryville.

Ambrosia beetles push out frass and sawdust in infested trees. The "toothpicks" sticking out from the tree truck is very diagnostic of infestation.

Gary is complaining about “laurel wilt”, a fungal disease, infecting sassafras and bay trees. This disease will also kill avocado trees. The red bay ambrosia beetle is responsible for spreading this disease. The ambrosia beetle will leave “toothpicks” poking out from the tree trunk as shown in the image above. Anyone seeing anything resembling the disease on sassafras trees or firewood should report it to their nearest AgCenter office or Louisiana Office of Forestry.

tomato aphids

Tomato aphids.
Photo: University of Kentucky

Anne complained about a clump of “spiders” on her tomato plants and wanted to know how to treat them.

AHA suspected that Anne saw aphids on her tomatoes. Aphids are soft-bodied insect, and they feed on the sap of plants causing damage and weakness in the infested plant. Treatments include Malathion®, Bifenthrin or Safer Insecticidal Soap ®. As always, read the label for safe and effective application.

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 Also, you can be on the “green thumbs” email list by submitting your request to the email 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.”

7/1/2019 6:38:17 PM
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