Fungus on Chanticleer Pear Tree - Ask Extension
I was told by an arborist that I have fungus on my tree. What type of spray would you recommend?
Knowledgebase
Fungus on Chanticleer Pear Tree #703937
Asked July 22, 2020, 12:06 PM EDT
I was told by an arborist that I have fungus on my tree. What type of spray would you recommend?
Clackamas County Oregon
Expert Response
Thank you for your question. There are at least 30 diseases affecting pear trees, about half of which are fungi. Each has a different treatment regimen, depending on the fungal species. Some sprays will do no good at this time of the year. So, before advising, we need the specific fungus identified. Photos would also be helpful. Thank you for more information.
Here you go... thank you!
Thank you. I was stumped, so I asked our chief plant pathologist, Dr. Jay Pscheidt, to look at the photos and give me his opinion. Here is what he says:
"Looks like about 3 or 4 problems. The first image seems to have eriophyid mites (which has been a common question this year) and/or powdery mildew. Wish the leaf symptoms were clearer. The second images does remind me of fire blight but this cultivar is considered resistant (which does not mean it doesn’t get it). There are also all these yellow splotches that are not normal. The third image is too out of focus to tell much of anything. It kind of looks like scab but also does not look like it. So, a few things to do. First, have them explain a little more about what they are concerned with, maybe an in focus image? Also, a more direct way of dealing with this is to assume the arborist is correct and just give them the link to the home orchard pest management guide with the explanation that the tactics mentioned will also work for flowering pear as well as fruiting trees."
So, here is the link that Dr. Pscheidt is referring to: https://catalog.extension.oregonstate.edu/ec631
I hope this is helpful. Good luck!
"Looks like about 3 or 4 problems. The first image seems to have eriophyid mites (which has been a common question this year) and/or powdery mildew. Wish the leaf symptoms were clearer. The second images does remind me of fire blight but this cultivar is considered resistant (which does not mean it doesn’t get it). There are also all these yellow splotches that are not normal. The third image is too out of focus to tell much of anything. It kind of looks like scab but also does not look like it. So, a few things to do. First, have them explain a little more about what they are concerned with, maybe an in focus image? Also, a more direct way of dealing with this is to assume the arborist is correct and just give them the link to the home orchard pest management guide with the explanation that the tactics mentioned will also work for flowering pear as well as fruiting trees."
So, here is the link that Dr. Pscheidt is referring to: https://catalog.extension.oregonstate.edu/ec631
I hope this is helpful. Good luck!
Thank you... was your concern on the fuzzy image the individual leaf?
I just went back out and noticed small ants were present on the leaves. I also included another photo that might be more helpful. All the arborist told me was that it was a fungus and it could be sprayed or plugged, which is what he Recommended. Beyond not really anything as he is most interested in charging me $171 per tree per month (5 trees) for a 3 month period. This seemed crazy to me so I am looking for a DIY solution.
I am unable to comment on the fees, but the time during which fungicides are effective are in late dormancy through budbreak, which is roughly 3 months.
If your plant has ants, they are probably there to eat the honeydew produced by aphids, whose sucking removes food from the leaves. The black spots may be sooty mold, which grows on the honeydew. Controlling the aphids will also control the sooty mold. Here is an article on that: http://ipm.ucanr.edu/PMG/PESTNOTES/pn74108.html#:~:text=Table%201.%20Some%20common%20honeydew-producing%20insect%20groups.%20,%28Obscure%20mealybug%29%20%20%20Whiteflies%20%28Silverleaf%20whitefly%29%20
Finally, just to illustrate the multitude of pests of this species, here is a complete listing of known pests:
https://pnwhandbooks.org/search/site/chanticleer%20pear
What you might want to do is to submit leaf samples (with each of the different symptoms on them) to the OSU Plant Clinic, so you have a diagnosis obtained under lab conditions: https://bpp.oregonstate.edu/plant-clinic
If your plant has ants, they are probably there to eat the honeydew produced by aphids, whose sucking removes food from the leaves. The black spots may be sooty mold, which grows on the honeydew. Controlling the aphids will also control the sooty mold. Here is an article on that: http://ipm.ucanr.edu/PMG/PESTNOTES/pn74108.html#:~:text=Table%201.%20Some%20common%20honeydew-producing%20insect%20groups.%20,%28Obscure%20mealybug%29%20%20%20Whiteflies%20%28Silverleaf%20whitefly%29%20
Finally, just to illustrate the multitude of pests of this species, here is a complete listing of known pests:
https://pnwhandbooks.org/search/site/chanticleer%20pear
What you might want to do is to submit leaf samples (with each of the different symptoms on them) to the OSU Plant Clinic, so you have a diagnosis obtained under lab conditions: https://bpp.oregonstate.edu/plant-clinic
