Galls? Nodules on Birch Leaves with Aphids Present

[Chuck]

Got it. I'll plan to spray everything tonight. And I'll do another pass in a week and perhaps one or two more. You think 4 applications at one week intervals? Or more frequently? I really appreciate your guidance.

Once per week should be sufficient. Just keep a close eye after spraying and observe when you start seeing the nymphs and larvae again and adjust your spraying regimen to coincide.

 

[Jonny Klobber]

Covered almost the entire yard over two evenings with neem oil. Wasn't able to reach the tops of our taller trees, but got everything up to about 15 ft or so. Are arborvitae, spruce and pine affected by leafhoppers or aphids? Haven't seen any on them but wasn't sure.

From what I've read it takes 3-4 days for the neem oil to work. I'm still seeing tons of leafhoppers, but won't worry unless I still see them in a few days. Another product that I have on hand is Captain Jack's Deadbug Brew. I know this works in a completely different way than the neem oil (kills them from the inside via ingestion rather than smothering them like neem). Would it hurt to hit the most affected plants with the Deadbug Brew as well? The red osier dogwoods, bee balm and Clethra are the plants that are really getting hammered. If I shake any of those, several leafhoppers come flying out every time. Hit those with Deadbug Brew tonight or just wait for the neem oil to do its thing?

 

[Chuck]

You are correct in that Neem takes 3 or 4 days to kill. Neem kill by ingestion, by smothering and by contact. It doesn't kill an insect immediately by contact but changes the insect's physiology which leads to death. The Deadbug is a spinosad based insecticide that is distilled from a soil bacterium. It has a fairly rapid kill time and kills by contact and by ingestion. I would go ahead and spray the Deadbug as well as they will not counteract each other. I would still follow up in about a weeks time with another spray of Neem. The Neem will smother the eggs and disrupt the entire reproductive cycle.

 

[Jonny Klobber]

Sounds like a plan.