kitty-lover
Full Member
Posts: 27
Joined: Mon Jul 10, 2006 9:18 pm
Location: central illinois

Bag Worms

My large blue spruce is covered with bag worms on one side. It's also dead looking. Can anyone tell me how to control these and if the dead part of the tree will come back again?
Thanks!
Sue
Illinois

opabinia51
Super Green Thumb
Posts: 4659
Joined: Thu Oct 21, 2004 5:58 pm
Location: Victoria, BC

I doubt that the dead part of the tree will come back but, you never know.

I'm not familiar with bag worms, but with tent caterpillars we just burnt them. Also, it would help to research to see what the predators of bag worms are and plant plants that will attract the predators. Also, research to find if there are any plants or other means of repelling the bag worms.

Anyone have any information on these guys?

Guest

Waiting until the bags are permanently attached in August, means hand-picking is about the only effective treatment.

MaineDesigner
Green Thumb
Posts: 439
Joined: Thu Nov 09, 2006 11:17 am
Location: Midcoast Maine, Zone 5b

B.T. (Bacillus thuringiensis) is effective on bagworms if you treat them when the larvae are around 1/4" or smaller.

opabinia51
Super Green Thumb
Posts: 4659
Joined: Thu Oct 21, 2004 5:58 pm
Location: Victoria, BC

Thanks Maine yes, BT is a bacterium spray that is commonly used in industrial organic gardening.

However, I would say that more research as to the population densities and localities of Bacillus thuringiensis need to be done before everyone goes out and starts using this bacterium everywhere.

Nature has existed for a long time without the introduction of foreign organisms to the mix and an introduction of a new organism can wreak havoc on functioning ecosystems.

I currently do not have the time to review the peer reviewed literature on this topic but if someone else does.... please do!



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