Kermes scale on red oak

Asked June 23, 2016, 9:38 AM EDT

Our red oak is dropping young branches (green, approximately 12" with clusters of leaves) as well as individual leaf clusters for the last couple weeks. A tree service diagnosed Kermes Scale when we purchased the home last winter, but we took no action then.

Is it appropriate to have the tree treated NOW, or wait til fall season? Articles here mention sprays and injection treatment for spring and fall, but nothing for summer.

I regret waiting on treatment and don't want to see the tree suffer irreparable damage.

Jefferson County Colorado

3 Responses
Please see the above CSU Extension Plant Talk which discusses Kermes scale and management.
Fall is the time to treat the trees because that's when the crawlers (young) have hatched and moving about. It seems counter-intuitive but that's how their life cycle works.
Keep the tree watered during hot dry spells in summer and have it treated this fall.

Thanks for the fast response, Mary. So just water through the summer, nothing else to intervene the bugs or aid the tree?

Right, just care for it well and take action this fall.