Webworms in Oklahoma

Those webs, however, have nothing to do with spiders. Oklahoma is experiencing a wave of fall webworms, which have simply been more abundant than in years past.

“In some years we barely notice them at all,” said Eric Rebek, associate professor in Oklahoma State University’s Department of Entomology and Plant Pathology. “Some years are bigger than others, this year we just happen to have a bumper crop of these caterpillars.”

The webworms prefer pecan and persimmon trees, but can branch out and feed on other trees as needed. While the webs may be unsightly, there is not much to worry about concerning the health of the trees.

“The webworms will do no damage to the actual pecan, but it can defoliate the tree,” said Jackie Lee, OSU Cooperative Extension entomologist. ”The only reason you should be concerned is if you have a lot of webs in the tree, it could cause severe defoliation.”

Even then, the long-term impact on the tree will be minimal.

“By the time they start doing their damage, the trees have already produced enough sugars and starches through photosynthesis to make it through the winter,” Rebek said. “It’s not going to harm the tree at all, as the leaves are soon to fall off anyway.”

Younger trees are more susceptible. Lee suggests removing any webs and webworms from trees less than five years of age.

“It’s very simple,” she said. “Just take a branch and run your hand along the branch to remove the webworms, or prune out those branches, making sure to dispose of the worms.”

The webs themselves are created by a group of worms for protection as barriers from their own natural enemies, like arthropod predators, parasitoids and birds. Soon the worms will begin to fall from the webs and begin the next stage of their lives, pupating in the soil.

The webs will naturally degrade as natural elements, such as wind and rain, take hold.

A SUNUP video on webworms is available at http://sunup.okstate.edu/category/seg/2015-second-half/091915-webworms/.

###

Oklahoma State University, in compliance with Title VI and VII of the Civil Rights Act of 1964, Executive Order 11246 as amended, and Title IX of the Education Amendments of 1972 (Higher Education Act), the Americans with Disabilities Act of 1990, and other federal and state laws and regulations, does not discriminate on the basis of race, color, national origin, genetic information, sex, age, sexual orientation, gender identity, religion, disability, or status as a veteran, in any of its policies, practices or procedures.  This provision includes, but is not limited to admissions, employment, financial aid, and educational services. The Director of Equal Opportunity, 408 Whitehurst, OSU, Stillwater, OK 74078-1035; phone 405-744-5371; email: [email protected] has been designated to handle inquiries regarding non-discrimination policies: Director of Equal Opportunity. Any person (student, faculty, or staff) who believes that discriminatory practices have been engaged in based on gender may discuss his or her concerns and file informal or formal complaints of possible violations of Title IX with OSU’s Title IX Coordinator 405-744-9154.

REPORTER/MEDIA CONTACT:
Sean Hubbard
Communications Specialist
Agricultural Communications Services
145 Agriculture North
Oklahoma State University
Stillwater, OK 74078
Phone: 405-744-4490
Fax: 405-744-5739
Email: [email protected]