How do I kill bagworms on my leylands?

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GLOBOTREE

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I am ashamed of it but my row of leyland cypress trees has become infested with bagworms. Four days ago I sprayed the trees liberally with liquid Sevin and fertilized the trees with 10-10-10.
Does the poison even penetrate the silky bag? I still find a lot of them are alive inside their bags.
Also you can see some of them crawling around, feeding I assume.
Thanks
 
I've used the systemic, Orthene, successfully. You can also use BT although it is more effective against young larvae, crawlers.
 
Might as well burn them down.

In my experience, once you can see the bags, you're toast unless you go off-label on the Dursban and nerve gas. They're pretty much immune to everything up to and including nuclear war by then.

What you need to do next year is spray in late May with Sevin and/or Malathion when the little buggers are maybe 1/8"-1/4" long. They look the same as they do now -- they're just tiny.

I nearly lost several Leylands a couple years ago, I was so overrun with bagworms. OTOH, the bagworms girdled branches that I couldn't reach to trim! :clap:

I'm still switching to Thuja x "Green Giant," though. YMMV. Bagworms are evil. :angry2:
 
Good luck with the Thuja's. I planted some about 5 years ago and they're like 2" taller than when I got them and I think they're starting to kick off now. Nothing like what I'd thought they'd be but must be the oaak trees or something that they don't like.
 
Bag Worms

I get bag worms on my four Arizona Cypress (Blue Ice), which I planted 3 years ago. I picked off about 300 two years ago, then about 150 last year. It takes me about 2 hours to do a thorough search.

I drop them in a 5-gallon metal pail, add a little diesel fuel, and burn them. I hope the number diminishes each year.
 
...i use the "bayer" brand. yeah, in the spring they're easy to kill.

...i mix light & spray often (couple times a week) but i start very early. end of march, early april.

...you get the little buggers in the spring, and keep 'em off, your conifers will look nearly as good as new the next season.

...trees are valuable, much more so than the cost of tools to treat them properly. if you've more than a couple of trees, get a real sprayer & drag it around in a garden tractor trailer. works for me.

...too late now to do much, they've already done their damage.
 

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