Can I get a confirmation of my diagnosis of pear rust, pics included

Asked May 4, 2018, 9:36 PM EDT

Last year crop was a total failure due to this. This year I have gently removed close to 6 small fruit starts. I just found some leaves on the pear with these spores. I have been treating the soil and the tree with neem granules, for soil, and neem oil spray for leaves and branches and fruit. Spraying about every 2 weeks. Still not under control. Please advise on any other methods besides cedar tree removal. I haven't found any cedars close by with this rust yet. But I believe a western red cedar in the adjacent yard, field was orangish in color about 2 years ago. Looks green, bright green, now.

Washington County Oregon pear trees horticulture pacific coast rust

3 Responses

Yes, your pear tree is infected by Pacific Coast Pear Rust. (If it's any consolation, many other pear trees in our region also have rust this year.) Significant outbreaks occur every several years. Both Asian and European cultivars are susceptible. 'Winter Nellis' is severely affected whereas 'Bartlett' is typically less affected. Some years, ‘Bartlett’ can also be seriously affected.

Most rust diseases are interesting in that they require two hosts to complete the life cycle. With Pacific Coast Pear Rust the alternate (2nd) host is incense cedar.

At the time pears were in flower, bright orange telia (jelly-like blobs; the fungus) were on the infected cedars. (See attached image.) Airborne spores from the jelly masses infect susceptible pears, both flowers and leaves.

In order for a spray to be effective, it must be applied when the swollen, orange telia are present on the cedars. In western Oregon, that’s usually during bloom. (In other words, it’s too late to spray this year.)

Another glitch is that suggested products are available only to commercial pest control companies. (If you may hire a company, consider reviewing “Selecting a Pest control Company” – it’s at http://npic.orst.edu/pest/selectpco.html.)

Do not apply pesticide to the soil. It won’t affect rust.

Your strategy for the remainder of this year will include (1) good sanitation (collect and discard infected leaves and fruit); (2) remove and discard any infected woody parts; and (3) if the incense cedar is on your property, consider removing it.

Thanks! I should clean up, remove infected pear growth. Can other plants Apple, plum, figs, nuts, olives get infected by this? Explain proper removal procedures to Stop further spreading.
what profess companies can do fungicide spray for next year. I read article but not clear on who does fungicide applications locally. Lawn care companies or pest, insect companies? Thanks agian



Pacific Coast Pear Rust is specific to pears.

Clean-up means to remove, and trash, infected parts, both on the tree and on the ground.

If you have an incense cedar on your property, you can consider removing it. If a neighbor also has an incense cedar, removing yours won't help stop the rust on the pear.

Various professional pest control companies spray fruit trees. Look in the Yellow Pages, online or in a phone book, perhaps under "Landscape Management" or "Pest Control."

Or go online and use the search phrase "pest control portland oregon" or "garden pest control portland oregon" -- but omit the quote marks.

You may need to contact a number of companies to locate one that sprays fruit trees.