White foam on Dogwood

Asked June 27, 2018, 5:58 PM EDT

My Ivory Halo Dogwood shrubs have a white foam on them with little black shiny bugs. What causes this and what can I do to treat this? Is there something organic that is effective or do I need to use a herbicide? Also the edges of the leaves of my small trees are all turning brown. Not sure what the tree type is or what is turning the edges brown. I did see small spider webbing on a few of the branches but otherwise could not find what the problem is.

Wexford County Michigan

1 Response

The foam that you are seeing on your dogwoods is most likely spittlebugs which are sap-feeding insects that create the "spittle" as they feed on the host plant. These are unsightly but not often fatal to the shrubs. See the website below for more information about the spittle bug life cycle.
https://hortnews.extension.iastate.edu/1995/6-30-1995/dogwood.html

As for the trees with browning leaves, this may be leaf scorch which can be caused by a number of environmental factors. See the web site below for more information about the possible causes and what you can do to further investigate the cause.
https://extension2.missouri.edu/g6881
Since you say you saw webbing on the leaves, I would also suggest that you look very closely at the underside of the leaves (ideally with a magnifier or hand lens) to see if spider mites or another insect may be causing the trees to be stressed. Reply back if you do find insects and we can figure out next steps.

Hope that helps.