Pear Tree Blight? - Ask Extension
Hi, we transplanted a pear tree two years ago. Last spring we got a horrible grasshopper infestation in the area, and despite my best efforts with org...
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Pear Tree Blight? #923908
Asked January 25, 2026, 1:39 AM EST
Hi, we transplanted a pear tree two years ago. Last spring we got a horrible grasshopper infestation in the area, and despite my best efforts with organic solutions, ate away most of the tree's leaves. It started to grow back Spring of 25, but then sort of seemed to falter, despite regular watering and fertilizer. Now, I'm seeing what I think might be fire blight, except there's no Shepard's crook type bending at the end of branches. I see a lot of blackened new branches and blackened leaves. Is this fire blight?
Weld County Colorado
Expert Response
Hi Sammie,
Thank you for reaching out to the Weld County Master Gardeners!
It can be really difficult to diagnose problems with trees this time of year, because many of the symptoms for various diseases are most noticeable when the buds are opening, the leaves are on the tree, and/or the tree is changing for the fall. They really just aren't easy to see when the tree is dormant. That can cause misdiagnosis.
I would watch the tree as it leafs out this year and see if there are any symptoms you notice. Then take photos of the symptoms up close, then the entire tree, and finally the tree with its surroundings. Also include your watering and fertilizing schedule/frequency (both during growing season and dormancy). That gives us enough context to start narrowing things down.
In the meantime, make sure to only look at reputable sources for fire blight (any website that ends in .edu) and stay away from AI generated answers, as you don't know where that information is coming from and other websites can be very unreliable. Here is a good resource I found on our website for Fire Blight - https://csfs.colostate.edu/wp-content/uploads/2025/06/Fire-Blight-Fact-Sheet-2.907.pdf. It has some good recommendations for pruning in the dormant season, so I would make sure to pay attention to those closely right now as February and early March are great times for pruning.
Hope this helps! I also hope that your tree rebounds and looks great in the spring and there is no need to follow up.
Sara
Thank you for reaching out to the Weld County Master Gardeners!
It can be really difficult to diagnose problems with trees this time of year, because many of the symptoms for various diseases are most noticeable when the buds are opening, the leaves are on the tree, and/or the tree is changing for the fall. They really just aren't easy to see when the tree is dormant. That can cause misdiagnosis.
I would watch the tree as it leafs out this year and see if there are any symptoms you notice. Then take photos of the symptoms up close, then the entire tree, and finally the tree with its surroundings. Also include your watering and fertilizing schedule/frequency (both during growing season and dormancy). That gives us enough context to start narrowing things down.
In the meantime, make sure to only look at reputable sources for fire blight (any website that ends in .edu) and stay away from AI generated answers, as you don't know where that information is coming from and other websites can be very unreliable. Here is a good resource I found on our website for Fire Blight - https://csfs.colostate.edu/wp-content/uploads/2025/06/Fire-Blight-Fact-Sheet-2.907.pdf. It has some good recommendations for pruning in the dormant season, so I would make sure to pay attention to those closely right now as February and early March are great times for pruning.
Hope this helps! I also hope that your tree rebounds and looks great in the spring and there is no need to follow up.
Sara
