New disease threatening apple and juniper trees discovered in Minnesota

(ABC 6 News) – The Minnesota Department of Agriculture recently discovered a fungus named Japanese Apple Rust.

It has not been found locally yet, but it’s clear precaution will need to be taken.

Japanese Apple Rust, , a disease affecting apples, crabapples, and junipers, has been confirmed in Minnesota for the first time. The disease is caused by the fungal plant pathogen Gymnosporangium yamadae.  

It comes from China and Japan but has been in the northeastern part of the U.S. for over a decade. It was discovered in Wisconsin last year and now has been found in Dakota, Rice, and Scott counties in Minnesota.

Japanese Apple Rust spreads between junipers and apple or crabapple trees. It travels through the wind, and experts say it’s hard to miss.

“They make very brightly colored spores and spots on plants. So on the apples and the crabapples, what we are seeing is bright red bright orange or yellow with a bright red ring spot,” said MDA Plant pathologist Michelle Grabowski.

The signs can be seen early on.

“Apple scab issues, apple rust issues, they all start on the blossom and develop on the apple as the apple grows,” Sekapp Orchard Fred Kappauf said. 

Kappauf tells us he has seen his fair share of issues with apples. 

Apple orchards have fungicides that are used to prevent other fungi from growing on leaves and infecting apples. There is an easier way to prevent the spread.

“Not having junipers planted on that property can help reduce places where that fungus is going to be able to overwinter from one season to the next.”

The good news for local apple orchards is that the fungi have not impacted apple production in New England, and it will impact Minnesota even less because only our first few cases have been reported. 

In the meantime, the MDA will monitor how these apple trees react to the fungi.

“Hopefully as time goes by, and it gets here and it starts to become an issue, they’ll have a good program for combating it.”

Anyone with apple trees who is suspicious of Japanese Apple Rust is encouraged to contact the MDA so that they can take a look and offer a solution.