What's Wrong with my Pears

Asked May 14, 2019, 1:14 PM EDT

Hello, My husband and I planted an espalier pear tree last year. With 2 tiers of 2 pear varieties. I believe they are Bartless and d"Anjou. The tree did wonderfully during it's first winter and there is healthy new limb and leaf growth. Both varieties/tiers bloomed and produced baby pears. However I noticed rust-like fungus on the pears. Could you please let me know what this is and how I can prevent it from happening again? At this point only fruit seem to be affected. I did not notice anything wrong with the leaves, limbs or trunk. I am including a picture of the pears with fungus. Thank you so much! Val

Benton County Oregon disease issues pear trees

1 Response

It looks like your pear has a fungus commonly called rust. There are two related types found in our area: Pacific Coast Pear Rust and Trellis Rust.

To complete its life cycle, this fungus alternates between pears and incense cedar or juniper. This fungus becomes a problem every few years depending on the environmental conditions in the spring. When the pear is flowering, the fungus is producing fruiting spores that look like orange jelly on cedar trees. Spring rains spread the spores to pear flowers.

For management: This year, keep fallen fruit and leaves picked up. Consider removing the alternate hosts, but keep in mind that the spores can travel long distances so this may not be a feasible option. There are no effective pesticides labeled for use by homeowners.

For much more information check out these publications from the PNW Disease Management Handbook. Note: these pages list fungicides, but these are only available to commercial pear growers, not home gardeners.
https://pnwhandbooks.org/plantdisease/host-disease/pear-pyrus-spp-pacific-coast-pear-rust
https://pnwhandbooks.org/plantdisease/host-disease/pear-pyrus-spp-trellis-rust-european-pear-rust

Take a look through those descriptions and let me know if you have any questions.
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