Ambrosia Beetle Surprise

9ah-figlet

9ah-figlet

Well-known member
I just had my 1st ambrosia beetle (AB) attack, which was a real surprise as I thought we were far enough in the season that they aren't a problem anymore. It was also shocking at how quickly they worked--trees were fine Friday AM but looked like this today. The loose sawdust caught my eye first because I thought it was mold, then I saw the tell-tale toothpicks.
IMG_4962.jpeg
IMG_4971.jpeg
These two trees (Proscuitto Unk [top] and Campaniere [bottom]) had to be chopped pretty severely, and I took a limb off a WM#1. I will burn the infected material this afternoon. I've moved the stumps away from the main fig patch so that their odor doesn't attract anymore ambrosia beetles into my healthy trees. The trees that had been attacked were slower to wake. They kept scratching green and some had buds so I was patient. I still don't know what actually weakened them till they were susceptible to AB damage as my potted trees overwinter in the garage.

Lessons learned
  1. Ambrosia beetles ARE this far north!
  2. A minimal exposure to below freezing temperatures is enough to damage trees so that the AB beetle is attracted to them (There were only 3 days of low-30s temperature after I moved them outside and no temperatures below 30.)
  3. I need to treat trees proactively with Permectrin to prevent this. I had applied Permectrin II Insecticide (https://www.amazon.com/dp/B0042LGX6S) once in early May when Maryland and Virginia were reporting heavy damage. I thought it was a purely preventative measure because I've never seen them in my area before. I will treat more frequently (every 1-2 weeks) when it is dry and I may consider changing to a commercial strength.
  4. My timelines for spraying are about 1 month behind the DMV area. I need to keep spraying after May.
  5. I should move trees that are slow-to-leaf-out away from healthy trees as a precaution so that they do not attract AB.
 
Thanks @ktrain

I checked this afternoon, and found they infected their first healthy leaved out tree—a La Bourgeoisie.

I noticed a speck of white this AM, and it grew to this by 4 pm (look near node).
IMG_1901.jpeg

I’ve chopped well below the lowest hole, and hope I caught it early enough.

BFF gets a lot of attention on the forums, but ambrosia beetles seem far worse. Instead of losing this season’s crop, you lose the entire trunk until the lowest hole. I had to cut my Prosciutto Unk to the ground.
 
I agree about the beetles being worse than BFF...Sheesh I cut my Celeste down 4 yrs in a row. (In ground)
I keep a syringe around just for battling them, give them a dose of the concentrate.
Seems to work, but you have to catch it in time....which isn't easy to do.
 
ktrain said:
I agree about the beetles being worse than BFF...Sheesh I cut my Celeste down 4 yrs in a row. (In ground)
I keep a syringe around just for battling them, give them a dose of the concentrate.
Seems to work, but you have to catch it in time....which isn't easy to do.
Click to expand...
I don't even know how you can catch them in time, Would you have tried to just "stab-n-spray" the photo I just posted? Since I only had to cut 4-6 inches and I'm headed out for dinner, I just chopped quickly.
 
9ah-figlet said:
I don't even know how you can catch them in time, Would you have tried to just "stab-n-spray" the photo I just posted? Since I only had to cut 4-6 inches and I'm headed out for dinner, I just chopped quickly.
Click to expand...
If I see only 1 or 2 holes...I will fill the holes with concentrate...if they keep hitting it then I'll take it down.
But painting it after the first attack and injections....might help.
 
Carmelo said:
Wow that really sucks. Hope the trees recover and you got the treatment on time . These are really nice varieties you got there.
Click to expand...
Thanks--I have a big collection (trying to get down to 160 trees)--just not via the %^*$^ ambrosia beetle!

I liked your nice posts on Vince #3. I've got two trees rooted last year, but they haven't fruited yet.
 
GoodFriendMike said:
Have not tried paint. But lime wash and the IV organics stuff did not work for the beetles.
They both help with other bugs. But not these. Lost a lot this year because of them.
Cut, seal, burn what you cut and hope for the best.
Click to expand...
I keep hearing latex paint helps...Just hesitant to put it on my trees.
I didn't really think the lime wash would work, but sealing wounds does help.
Nothing you can do about frost damage though...other than take them inside.
 
Ouch - that’s a rough one.

I’ll keep a look out on mine since I’m just a bit north of you, though I think my trees are far enough along now.

On another note, what type of matting do you have on your pots? Do you purchase in sheets and cut to size? They look really nice.
 
bushdoctor82 said:
Ouch - that’s a rough one.

I’ll keep a look out on mine since I’m just a bit north of you, though I think my trees are far enough along now.

On another note, what type of matting do you have on your pots? Do you purchase in sheets and cut to size? They look really nice.
Click to expand...
My healthy trees are getting hit too. Be on the lookout—I used to think it wasn’t a problem. They can be attracted to other (non-fig) trees nearby and then infest your healthy ones.

Yes, the “mulch mats” are rolls of coir from Greenhouse Megastore:

www.greenhousemegastore.com

Gardener Select® Bulk Roll Coco Liners

Gardener Select™ Bulk Roll Coco Liners come in different widths and can easily be cut into different shapes and sizes to meet your needs. Coco liners provide healthy water retention in your soil while still providing proper aeration and drainage.
www.greenhousemegastore.com www.greenhousemegastore.com

I cut them to size with the rotary cutter I use for sewing. I use 12x12 for the 8-gallon grow pro pots and the cut slits for the irrigation. There’s a rough side and a smooth side—pretty sure the smooth side goes out to last longer. I got the idea from Bass from Trees of Joy who uses precut round ones. They’re light, stop weeds, should help w/water evaporating too quickly. If I need a thicker layer of mulch, I may add rice hulls (which tend to blow away at larger pot sizes). Let me know if you want to try some.
 
I got another toothpick from 4 pm till 8 pm. These f>cker$ never stop. Luckily (?), it was in a tree I already chopped. I just cut it lower again.
IMG_4989.jpeg
 
ktrain said:
If I see only 1 or 2 holes...I will fill the holes with concentrate...if they keep hitting it then I'll take it down.
But painting it after the first attack and injections....might help.
Click to expand...
I’ve been doing the same. And then if they don’t leaf out or recover I chop them down.
 
Last edited:
You must log in or register to reply here.
Back
Top