Dwarf Alberta Spruce - Bagworms
Many houses in the neighborhood have
Alberta Spruce trees/bushes as part of their landscaping. This afternoon
our across-the-street neighbor asked my husband and me to come take a look
at one of his four bushes.
It is in the middle of a row of four, and it looks dead from a distance.
When we got close, some of the brown branches moved! Yuck.
there's some sort of black grub-thing living inside a brown cocoon that
blends in with the dead-looking parts of the shrub. When the grub-thing
moves, it seems to take the cocoon with it.
I kid you not -- this bush was CRAWLING with the critters. Some were even
on the ground moving around, and attaching themselves to surrounding
Any advice you can give on what these things are, how to get rid of them
and whether we need to be concerned for our own Alberta Spruces would be
It sounds like you have bagworms.
Bagworms feed on junipers, pines, spruces
and even deciduous trees, and it sounds like they've found your Alberta
spruces. Deciduous trees can reproduce lost foliage easily, but evergreens
have a tougher time with a bagworm infestation, so this could be a problem
for your spruce.
Bagworms feed on the foliage and then attach bits and pieces to themselves
(as such, they may be the originators of the "mobile home").
protected within, so at this point hand-pick them and throw them away. The
eggs overwinter in the female's bag (she never leaves home), so removal of
the bags definitely helps control them.
Chemical controls should be applied earlier in the year, when they are just
starting. Mid to late June would be the approximate timing for this.
sure to check the label of the material you select to make sure it will work
on bagworms, and follow the label rates for application.
You may want to fertilize the plants this fall, too. Hopefully the
heavily-damaged plant has enough stored energy to resprout in the spring,
but only time will tell at this point.
Ask our Arborist a question. E-Mail us at:
Top of Page
Back to Alberta Spruce Trees