Azalea bark scale
Is it possible for Azalea bark scale to have been in the unit of hemlock bark I had delivered? I did not notice the white egg sacks until about three weeks after I spread the hemlock bark. I found eleven azaleas with the scale and three rhodies. I removed the azaleas and cut back the rhodies to trunks. I drenched the root zone of all remaining plants.
Azalea bark scale is very common in Lane County.
Did the hemlock bark have the eggs or adults.? IF properly composted the bark should not be infected. Check with the people who delivered the bark. If you got just ground up wood materials, the chance increases greatly.
Web site: http://oregonstate.edu/dept/nurspest/azalea_bark_scale.htm
Control is very easy with a good dormant oil spray in March on any plant that has the azalea bark scale.
To have that large of an infestation, the azalea bark scale was probably around for some time. Check other plants and neighbors for infecting plants.
Thank you for your advice.
The hemlock bark has small pieces of wood throughout the product. I did did not see eggs or adult scale when spreading it. My neighbors do not have any eggs on their plants. One blueberry bush of our neighbor had a few egg sacs and it was close to the bark pile on our driveway. We spread the bark in a couple days. driveway
Good investigation in looking for the azalea scale. It doesn't look like the scale came from the neighbors.