Webworms (...and bagworms)

Webworms or bagworms...which do you really have?  Many people have been asking me about "bagworms" as of late, but after asking a few questions I discover that they have webworms.  So, what's the difference?

Bagworms:

· Form small cases that hold larvae, pupae, or female adults and eggs

· Cases are often found on evergreen trees & shrubs such as cedar, juniper, cypress, or pine

· Cases are made from silk and plant material laid down similar to shingles on a house, overlapping in layers

· Newly hatched larvae spin a silken thread & either are carried to a new plant by wind or attach themselves to the plant they are on and begin to build their own silken bag

· Bags remain on plants even if bagworms are dead

· Bags are transportable; larvae carry them along as they move about the plant

 · To manage bagworms, handpick bags off the plant and dispose of them

Webworms:

· Spin webbing over branches of host tree to enclose foliage they feed upon

· Attack over 88 species of plants, including fruit, nut, and ornamental trees and shrubs

· Use web as a protective covering; spin webbing immediately after hatching out of egg

· Webbing remains on tree even if caterpillars are dead/ no longer there

· Webs can be pruned out of the tree or opened with a stick/ spray of water to allow predators to eat caterpillars

· When using a pesticide, webbing still needs to be opened

Webworms invading Austin

I've been receiving calls on webworms that are in trees surrounding Ladybird Lake.  we also have webworms in a tree at the Demonstration Garden.  Since it's a demonstration garden, I'm using the webworms as a....you guessed it!....demonstration.

I'm sure that you have been told (even possibly by me) that you can manage webworms by removing webs and knocking them out the tree with a stick.  I decided to see how well it actually works.  So far, it's going pretty well.  I started two weeks ago when we had a pretty good covering of webs on the tree.  I took a metal pole (actually the handle of an insect net which I had in my office) and removed as much of the webbing as I could from the branches.  I made a pile of webbing and caterpillars on the ground while removing the webs and that got taken to the garbage when I was finished.  I also whacked on the tree branches a few times after removing as much of the webbing as I could to dislodge any caterpillars.  I repeated the process every Monday and Friday.  Today when I checked on the webworms, there was only one small new web spun very close to a small branch.  The rest of the area has dead leaves and some loose webbing clinging to the branches, but the webworms aren't actively there anymore.  I removed the small section of webbing I found today and whacked the branch.  I'll check the situation again on Monday.  While I'm not completely done with the demonstration, so far it is looking pretty good.
 

Webworms on 6/13/14

Webworms on 6/20/14

Webworms on 6/27/14