Hi Kelly,

This is a pretty severe infestation of hawthorn mealy bug - if you look closely, you'll see the crawlers and some of the adults, which have a waxy, cottony coating.

As fall nears, the insects move to the bark and you can start to control them using horticultural oils, which will smother them. You'll want to spray on a nice day when temperatures are warm - and repeat this as you notice living insects. Follow the directions on the label of any product you use.

There are different oils available - right now you'll want to get a "dormant oil" or similar. You can talk to the greenhouse and nursery staff. Here's a fact sheet: https://extension.colostate.edu/topic-areas/insects/insect-control-horticultural-oils-5-569/

Hi Kelly,

My apologies - I don't know when you responded, but I apologize if was awhile ago. There was a glitch with the system.

YES, that looks like the correct product - and be sure to mix it at the recommended rate. More is not better in this case. 

Good luck! I hope you have good success and no mealybugs next year.

Thanks! Yes, I sprayed according to instructions, then waited a few days, then sprayed the whole tree w water from the hose sprayer. Much of the white came off the truck w the water spray yea!  Then I waited about 5 days and sprayed the whole tree w more oil mixture (this was on a warm day before storm).  It looks a lot better :-).   I believe the instructions said I can spray again (early Spring) before the tree comes out of dormancy.

Thanks again! Kelly

Hi Kelly,

Yes, spray again in the spring on a warm day. Later spring might be better (late March/April) and keep an eye out if you see any crawlers (babies). 

--Alison