Control for aphids and scale in silver maples

nuthin_special

nuthin_special

Location
Thunder Bay, Ontario
We're having some huge issues with silver maples in our city being attacked by lecanium scale and wooly alder aphids, especially on street trees. Many homeowners are willing to remove their trees to fix the problem.

I'm wondering if anyone in ontario is familiar with a good treatment? Imidacloprid (confidor) is available for trunk injection however the label doesn't include silver maple. Treeazin (azadirachtin)is also available but the label appears to not cover silvers. We can use ace caps, but i don;t like them because of the high number of drill holes and implants per tree.

We can also use a few sprays (carbaryl and acephate) but regulations involving sprays, especially with public trees, make this option very undesirable.

What am I missing?

v
 
horticultural oil? are the regulations for spraying oil easier than if you were spraying chems?

or how about some good predators? lady beetles for both... lacewings and a butterfly (caterpillar) called The Harvester find those aphids delicious.

there must be a lot of native alder around there? if they were willing to remove the maples, maybe they would be willing to remove the alder preemptively?
 
Honestly I can say I ahve had far tougher jobs.
Avoid spraying at all costs. Run with the wolves go down with the pack.
The Hammer is sick!
These types of jobs will find you if you refuse to cut down viable trees.
They will find you!
Keep on Keepin on!
 
Im actually trying the acecaps route this week on a silver for the first time. Also on some small magnolias combined with soap. The silver is too big to spray!

Might be worth the drill holes if removal is the only other option.
 
I'm certain that soap won't give adequate enough control. Also, spraying soap on mature silver maples isn't really feasible.

Have you had success with soap on mature trees to control aphids and scale?

Matdand - acecaps will work, it's certain. But applying them every year or every two years to trees and expecting them to grow problem free for 50-80 years i think is too much to ask. That is too much wounding of vital trunk tissues to expect a tree to deal with.

There might not be an answer here.

For our private clients, they may end up choosing removal and if I can't offer them an alternative option, what am I to do? For the municipal clients, they can't just remove 2500 silver maples from the inventory. For us that would be about 10% of our urban canopy cover.

Aerial sprays of acephate? That would stop many phone calls of complainy people.

v
 
Well ash trees are going to have to live with some good driling for the next few years, hence the spiral pattern up the stem. Maybe not quite as much as acecaps, but still, if its the only recourse...

I think Acecaps are labeled for two or three seasons of treatment, so hopefully I wont need to repeat every year, or ever for that matter.
 
Dude, ace apps give about 30 days of control. Read the label a bit more closer like.

Ace caps are cheap but not necessarily better. Look into treeazin, it may be a better fit.

Perhaps the best tool to fight tree pests (at least those that don't actually kill them) is really good education of the people that live under them.

Vince
 
Thanks Rope, but when I said your avatar was tough i didn't mean the job (which i'm sure was tough) i meant you... you a bad mama-jama!

nuthin, I think this is a job for The Harvester. i kinda just wanted to say that, but it actually might be...

out of curiosity what is the alder population like there?
 
My bad, I just reread the label and it does say 10-12 weeks of treatment, 18 max. I got mixed upwith medicaps which says it can be effective for 2-3 growing seasons. My mistake.

Is treeazin registered for scale in Canada?
 
Wooly alder aphid likes to eat alder and silver maple. We have many million alders here but they are only in the forest and a menace to try to walk through.

Treeazin just had their label approved for more than just eab. It isn't registered for scale but.......

Vince
 
the woolies require both alder and silver maple to complete their life cycle, however, I don't know the distances they are able to travel to find the alder after they overwinter in the silver...

so not much alder in the landscapes huh? they must travel far...
 
Right, I forgot about that. There are lots of alders along creeks and in forested areas, that must be where they are hanging out. Never put much thought into it.

Still, most of the silvers we see are at least 500 metres from green spaces where alder may be.

I'll put a gps tracker on one and see where it goes. I think theres an ap for that.
 
Vince, I would worry less about the species on the label than what type of insect the product is good for. Of course imidacloprid will work, but I don't use the product for a variety of reasons that most people are aware of. AzaSol is now approved for injection, which I believe it was intended for based on the price. I would recommend that. It's very effective on scale and aphids.

Tom
 
In addition or instead of any chemical you apply you can apply a 6 inch (15cm) band of Tanglefoot around the trunks to exclude ants from the equation. Keeping the ants out will increase the success rate of predatory and parasitic insects. If you can use that in Canada, I don't know.
 
You must log in or register to reply here.

New threads New posts

Back
Top Bottom