Periodic Cicadas Emerging

[Piedmont Bonsai]

Is anyone worried about the periodic cicadas damaging their bonsai? I wasn’t doing bonsai last time they came out so I’m not sure if they will cause damage, but I’ve seen pictures of damage on landscape trees and I’m a little worried as I have a decent amount of money invested in some trees.

What actions do you all take against cicadas?

 

[gooeytek]

potted plants, not so much. the larva mainly affect roots of plants in the ground.

I don't worry about them at all.

 

[penumbra]

If you are in a zone expecting a swarm, it may be worth getting some insect netting. It is cheap and easy to use and can be helpful for bonsai on a bench. Plants on the ground are much less likely to be affected.

 

[Gabler]

They will not appear in a swarm and devour your trees overnight the way pine sawflies do. However, they will kill the odd branch on a landscape tree.

It may be a good idea to treat your trees prophylactically with insecticide. I use a granular systemic absorbed through the roots. It kills things that actively consume the tree, but not beneficial insects that merely come into contact with it. For that reason, I cannot comment whether cicadas attack bonsai trees. My trees were all fine last time, but I am unsure if that had anything to do with my insecticide treatments.

The granular systemic I use also doesn't seem to deter other types of arthropods, including spiders, centipedes, and isopods. I have tons of them living in my treated plants.

 

[Kanorin]

They will not appear in a swarm and devour your trees overnight the way pine sawflies do. However, they will kill the odd branch on a landscape tree.

It may be a good idea to treat your trees prophylactically with insecticide. I use a granular systemic absorbed through the roots. It kills things that actively consume the tree, but not beneficial insects that merely come into contact with it. For that reason, I cannot comment whether cicadas attack bonsai trees. My trees were all fine last time, but I am unsure if that had anything to do with my insecticide treatments.

The granular systemic I use also doesn't seem to deter other types of arthropods, including spiders, centipedes, and isopods. I have tons of them living in my treated plants.

Neat, can you share which brand of granular insecticide you use?

 

[rockm]

Not really much to worry about, particularly if you have small bonsai or smaller developing trees. I've been through two emergences over the last 20 years or so (two separate broods). Didn't have any damage to my trees. The bugs were pretty thick around the area for a couple of weeks, but they didn't really bother my trees. They occasionally crawled on them, but moved on (and no they're not going to lay eggs in your bonsai soil and they aren't going to damage the roots even if they do--you're going to repot the tree hopefully over the next 17 years right? ).

BTW, poison systemic or otherwise, isn't worth the trouble. It's not a big enough problem. It's like shooting a fly with a shotgun.

Cicada damage has been reported by some bonsaiists, though. Most Cicada damage on those trees is like the damage the cause on larger landscape trees--they split the bark on the ends of branches to lay eggs in the split. That split can kill off the end of the branch. The damage is called "flagging." I've not seen it on my bonsai in cicada years, but it can happen. Bird netting can help keep them off your bonsai, but that can be a hassle--particularly removing it as it can break off branching too if it gets snagged or tangled.

Bottom line, if your trees are under two feet tall have no "substantial" branching over 1/2" or so in diameter, you're likely not to have much issue.

 

[Gabler]

Neat, can you share which brand of granular insecticide you use?

I mix it up and use different brands with different active ingredients each year, but I believe I was using this when the cicadas last appeared.

https://www.amazon.com/gp/aw/d/B000BWZ9U8?psc=1&ref=ppx_pop_mob_b_asin_title

 

[Piedmont Bonsai]

Not really much to worry about, particularly if you have small bonsai or smaller developing trees. I've been through two emergences over the last 20 years or so (two separate broods). Didn't have any damage to my trees. The bugs were pretty thick around the area for a couple of weeks, but they didn't really bother my trees. They occasionally crawled on them, but moved on (and no they're not going to lay eggs in your bonsai soil and they aren't going to damage the roots even if they do--you're going to repot the tree hopefully over the next 17 years right? ).

BTW, poison systemic or otherwise, isn't worth the trouble. It's not a big enough problem. It's like shooting a fly with a shotgun.

Cicada damage has been reported by some bonsaiists, though. Most Cicada damage on those trees is like the damage the cause on larger landscape trees--they split the bark on the ends of branches to lay eggs in the split. That split can kill off the end of the branch. The damage is called "flagging." I've not seen it on my bonsai in cicada years, but it can happen. Bird netting can help keep them off your bonsai, but that can be a hassle--particularly removing it as it can break off branching too if it gets snagged or tangled.

Bottom line, if your trees are under two feet tall have no "substantial" branching over 1/2" or so in diameter, you're likely not to have much issue.

The branch damage is what I’m concerned about… I have 2 large 4 figure trees that I would be sick if they got damaged by cicadas.

 

[Piedmont Bonsai]

They will not appear in a swarm and devour your trees overnight the way pine sawflies do. However, they will kill the odd branch on a landscape tree.

It may be a good idea to treat your trees prophylactically with insecticide. I use a granular systemic absorbed through the roots. It kills things that actively consume the tree, but not beneficial insects that merely come into contact with it. For that reason, I cannot comment whether cicadas attack bonsai trees. My trees were all fine last time, but I am unsure if that had anything to do with my insecticide treatments.

The granular systemic I use also doesn't seem to deter other types of arthropods, including spiders, centipedes, and isopods. I have tons of them living in my treated plants.

I treated with granular imidicloprid in early April. I may spray with malathion when I get home and hopefully it will deter any cicadas from getting near my bonsai

 

[rockm]

The branch damage is what I’m concerned about… I have 2 large 4 figure trees that I would be sick if they got damaged by cicadas.

I have a very large oak, cedar elm, Bald Cypress, trident maple, boxwood and more that are all pretty valuable. The oak has branching thicker than a thumb. Didn't get any damage through two swarms, had the things crawling over trees for weeks. I really didn't worry about it. Landscape and woodland trees did get flagging though. In the scheme of things, bonsai aren't really a prime target for them.

 

[penumbra]

I would like to add a few things that are based entirely on my real life experience. First thing is that I regularly use the Bonide Systemic Granules, but mostly on my dozens upon dozens of tropicals. Cicadas are not there to feed on your plant. They are there to lay eggs. A systemic therefore will have no effect of adult cicadas. It may kill the eggs but I doubt it. Ask me how I know. I have had branches destroyed on some of my bonsai. I have had them on maple, oak, elm, and other plants. Mostly they ravage my landscape plants in the ground, but they also have affected my bonsai on benches, and the higher the bench the more the damage. I seldom see damage below 3 or 4 feet and mostly from about 5 feet and up.
It is important to mention that I live in a forest condition in the Northern Shenandoah Valley. My 8 acres of oaks and hickory have an understory of dogwood, redbud, fringe tree that are native and several other small trees I have planted. My plot is surrounded by hundreds of acres with thousands of wooded acres near by. Cicada really love those dogwood the best but my Japanese maples are a close second. I do have insect barrier fabric that I will throw over the benches and many of the maple if I need to, but it looks like our broods here will likely not have significant hatching this year.
All in all, I accept this nuisance like I do the squirrels and birds and grazing deer. They were here long before me and will be here when I am gone. The cicadas actually do more good than bad for the environment, but plant people still have to be prepared to deal with them.

 

[dbonsaiw]

I'm kind of looking forward to the double brood. Not a chirp in my neck of the woods yet

 

[Piedmont Bonsai]

So it begins…

 

[bwaynef]

I drove 75 minutes to my parents and we met for lunch. When we got out of the car, there was a noise off in the distance ...but from every direction. My kids asked (before I could) what the noise was, and my parents were surprised to learn that we don't really have them where we are.

I've never noticed any damage from cicada broods, even when I lived where I could hear them.

 

[Piedmont Bonsai]

Well I have damage on two of my Japanese maple bonsai. One is worth $1000 and one is worth $2500

 

[TimIAm]

How do you know it's cicadas doing the damage?

 

[Piedmont Bonsai]

How do you know it's cicadas doing the damage?

Its flagging from them laying eggs. They seem to have a preference for japanese maple branches

 

[shohin_branches]

I know the Chicago botanical garden has its collection protected right now.

 

[Bonsai Nut]

Weird. I have yet to see (or hear) a single cicada...

 

[penumbra]

Weird. I have yet to see (or hear) a single cicada...

Study the cicada maps and you will see why. It is really quite interesting. We don't have them this year.