Dear leavesofjoy 

I apologize for the delay in response, I believe the damage you are seeing is from Aphid producing a sticky honeydew and black soot. Aphids can range in color from pink to yellow to green to black.

The treatment for Aphids are listed below:

Wash aphids from woody plants with a strong stream of water or by wiping the aphids off a stem or leaf by hand. Aphid populations tend to be higher in plants fertilized liberally with nitrogen or heavily watered, so avoid practices that produce flushes of succulent growth.

There is a list of chemical control options as well such as insecticidal soap and horticultural oil. Please look only at the list column titled "home landscape chemical products"

https://pnwhandbooks.org/insect/hort/landscape/common/landscape-aphid

https://pnwhandbooks.org/sites/pnwhandbooks/files/insect/horticultural-landscape-ornamental/content/pdf/pdfs/insect23f-9chemicalcontrollandscapemrbawlbnk.pdf

Thanks for getting back to me, but this is not aphid damage. There are no aphids on the tree, and that is not aphid soot in the picture, it's small black granules like some kind of frass. It's wrapped up in a curled leaf that was rolled up by the insect with webbing. The leaves are skeletonized, which aphids don't do. Please take another look - I need a solution.

On Tuesday, July 18, 2023, 11:04 PM, Ask Extension <<personal data hidden>> wrote:

Hello,

It looks like what you’re dealing with on your quince tree may be leafrollers. Take a look at this resource from WSU on this insect pest, and see if the signs and symptoms match up to what you’re seeing on your trees: https://treefruit.wsu.edu/crop-protection/opm/leafrollers/. This resource also provides several options for management of this insect.

Good luck!

Best,

Evie Smith

Small Farms & Master Gardeners Coordinator

OSU Extension- Lincoln County

Thanks! The leaf part of it does look like the leafrollers. But I don't see any damage to the fruits or shoots, the only damage out there is the skeletonized leaves. Can that still be leafrollers? And what should I do at this point to deal with them? 

Hi there,

Yes– It could still be leafrollers even if the only damage you’re seeing is to the leaves.

Are you open to using chemical applications to control the pest? And how widespread is the infestation?-- About how many trees are affected?

Best,

Thanks for that info! I am also now seeing the pear slugs too, so I sprayed with a neem oil & soap mix, since that seems to cover many different pests. It's just 2 trees, and one is only slightly affected, since it's healthier overall. I keep my garden organic, so hopefully the neem will work, but I'm open to other natural ideas, also.

Hello,

Timing of whatever management practices you choose is important here– leafrollers are best controlled when they’re in their larval stage. You may need to make a couple of applications as more larva emerge (check the label of your products to see how frequently you can/should apply it).

I will note that controlling leafroller at this time of year is particularly challenging. The site I sent you before notes: ‘If, however, more than 5% of the shoots are infested in late July, some type of control may be needed to protect fruit from injury before and during harvest. Bt sprays have been effective against larvae feeding in shoot tips during late July and early August.’

Bt (Bacillus thuringiensis) is an organic material that you could consider applying as well- you’d likely be able to purchase a product with Bt at the same place you purchased your neem oil.

Good luck!

Best,

Evie

Thanks for this info- I will spray with some BT, and work on a schedule to get ahead of it sooner next year. I appreciate the help!