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Friday - November 08, 2013

From: Austin, TX
Region: Southwest
Topic: Pests, Shrubs
Title: Something damages leaves on Tecoma stans from Austin
Answered by: Barbara Medford


Help! Something is chomping my Esperanzas. I thought it was deer but they don't seem to be eating other yellow bells in my neighborhood. I think it's an insect. Something is completely stripping the branches, leaves and blooms. Some of the branches seem to be turning black on the tips. I just sprayed with some mild soapy water hoping that would help. Thanks!


According to this article from Butterflies and Moths of North America, Tecoma stans (Yellow bells) is a larval host for Paratreae plebeja, Plebeian Sphinx Moth. From that article:

"Life History: Caterpillars hide on the underside of stems during the day, and emerge to feed at night. Fully-grown caterpillars pupate in chambers in soft soil. Caterpillars of the second brood pupate and overwinter in their chambers.
Flight: One brood in the north from May-July, at least two broods in the south from March-November."

It would appear that if you have them this year, you will have them next year, so if it proves to be the case that caterpillars are causing the damage, please see this article from Home Guides on How to Get Rid of Caterpillars without Pesticides on Plants.
In an article from Arizona State University,we found this information about pests on Yellow Bells:

"Disease and pests: In the Phoenix area, Texas and phytophthora root rot fungi occasionally cause sudden plant death, usually only in heavy soils with a former agricultural use history. During late summer of good monsoon years, a leaf skeletonizer catepillar will ravage foliage on upper stems primarily. The damage to foliage is short lived and cosmetic, not lethal. Several chemical control strategies are available including a biological spray Bacillus thurengensis; however, given the growth habit of Tecoma and its rapid recovery after pruning, I recommend that one strongly head back (prune) infested plants and dispose of the damaged material.."
Since this plant is deciduous, we tend to agree that knocking down the caterpillars and trimming back damaged foliage will be sufficient, but you should carefully clean up and dispose of the cuttings and be aware you may be subject to a second attack next Spring.

From the Image Gallery

Yellow bells
Tecoma stans

Yellow bells
Tecoma stans

Yellow bells
Tecoma stans

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