What’s Growing on That Red Cedar?

Perhaps the strangest things that you might see each spring are the bright orange globs hanging in the eastern red cedar trees. They look a bit like orange marmalade being pushed through a garlic press. Moist to the touch and about the size of a golf ball, these ornaments adorning the cedars are actually fungi.

The life cycle of the cedar-apple rust fungus (Gymnosporangium juniperi-virginianae) depends on both apple and eastern red cedar hosts. It’s possible to find cedar-apple rust anywhere east of the Rocky Mountains where eastern red cedars and apples coexist.

For most of the year cedar-apple rust is hard to see. However, when spring rains moisten the hard brown kidney-shaped galls that over winter on cedar trees they develop bright orange spore horns. These are very conspicuous and make the cedar look like it’s fruiting. The spores are then blown, sometimes several miles, onto apple trees infecting young buds and leaves. Over the course of the summer the fungus matures and eventually spores are blown back to the cedar trees to overwinter as small galls.

The fungus does not permanently harm the eastern red cedar trees. However, if left untreated, cedar-apple rust will damage apple fruits to the point of making them unsellable. This is a major concern for orchard owners. Today, fungicide is used to prevent cedar-apple rust from destroying crops, but that wasn’t always the case.

In 1914, apple growers wrote the Cedar Rust Act of Virginia allowing them to destroy cedar trees on neighboring property in an effort to control the fungus. While most people enjoy eating apples, a lot of people also like eastern red cedar trees, especially if they’re on your own property. You can imagine how people reacted when they woke up to see their neighbors cutting down all their cedar trees.

This all came to a head in a classic 1928 court case where a judge determined that apple trees were more valuable than cedars, and therefore more worthy of protecting. Cedar tree owners would not be compensated for their losses, but would be allowed to keep the wood from the cut trees. Remember to thank those folks who lost all their cedars next time you bite into a delicious apple!

If you happen to be out on the next rainy day, try to find an eastern red cedar. Hopefully you’ll have a new appreciation for those bright orange galls and their complex history.

Have you seen cedar-apple rust fungus before? Tell us where and when in the comments!

44 thoughts on “What’s Growing on That Red Cedar?

  1. Elizabeth Boffoli

    I live in Dutchess county ny. I have a red cedar tree in my yard. We have lived here for 20 yrs and this is the 1st time I’ve ever seen this fungus on my trees. We had a couple mild winters and a very wet spring.

  2. Donna

    We have this rust in Richmond, RI. Approximately May 20, 2017. Very, very wet spring in RI this year.

  3. Pat

    Thanks for the information. I found a couple in some small cedars near the Winooski River in Vermont last week after it had been raining for several days.

  4. Rick

    Here in Ottawa, Ontario. Canada. my red cedar sprouted this type of fungus fortunately we do not have fruit trees we had many rain storms this season which contributed to this Phenomenon


  5. Pink Smoke

    I’m in waterford Michigan. I am out riding my dirt bike and came across a bunch of junipers with orange things on them. I thought I was in the movie “the blob” lol I was wondering if I touch the “blobs” with my hands will it spread to my apple trees when I get home? Should I quarantine myself before I go around my property?

  6. Michelle Schuettke

    I’m in Jamestown, Rhode Island we have them in our trees now too. My 9 year old brought one inside and was wondering what it was.

  7. Mandy

    I live in eastern Kansas and have a beautiful cedar tree on my property. I was outside taking pictures after a two day storm and noticed these orange squishy balls with tentacles, hanging in my cedar tree!!! I picked one off and decided to go online to discover what it is…. Yuck! I have been here for three years and this is the first time the tree has displayed them.

  8. Stephanie Smith

    I live in Stafford, VA and my cedars have this now. What fungicide is good to use on my apple trees?

  9. Deana Moore

    I’m in Cherokee Village, Arkansas and my kids and I were just trying to figure out what the huge orange looking clusters on the tree were. This is definitely what they are.

  10. d

    There’s Tribbles in my tree! Noticed these bright orange horned ornaments on our cedar, just after last night’s torrential downpour. We’re in southeastern Massachusetts.

  11. Sheryl Church

    We have these on our pines in yard, Grand Junction, Michigan. Had been looking for what it was when came across your blog. Thanks

  12. Sheryl Church

    We have them here on our tree in Grand Junction, Michigan. Was looking for info on what it was when found your article. Thanks

  13. Patti Adinolfi

    We’ve had a lot of strange looking fungus this year in Amissville, VA. This was one of them here in the neighborhood. I’ll have to find who has the apple trees now…

  14. Renata

    Just the other day took a beautiful picture of it at Audubon’s Stony Brook Sanctuary in Norfolk, MA.

  15. Rob Ryan

    Here in Harleysville Pa. we have the fungi,I don’t like it so I cut them off my cedars. Goodbye and go Cedars

  16. Shoop

    I’ve been fighting these for years, ruins my apple and my pear trees with rust. This year I found the globs and I’m going to cut what I can and see what treatment options for my new Apple trees

  17. Terri

    Several rainy damp days here lately on Long Island, NY. My red cedar looks beautiful with those fungal ornaments. Glad it’s harmless!

    1. Anne Voland

      For the second year in a row, I have cedar apple rust on my tree. And yes, it’s not far from my small apple orchard. Grrrrr!
      Shelburne, Vermont

    1. karen allwood

      Just saw them for the first time in 18 years on my cedar tree, is it because I planted an apple tree last fall in the front yard. Milton, DE

    2. Marty Roy

      We have them in Stilwell Kansas! Too many to cut off. But don’t like fungicides. What to do. They are disgusting. Slimy!!

  18. Anne

    Just noticed these weird orange globs on a red cedar this morning. ( in Vermont) We’ve just had three days of rain. Unfortunately, this tree is near my small apple orchard. I think I’ve got a problem!


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