Native Plants

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants

See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

rate this answer

Not Yet Rated

Monday - May 04, 2009

From: Boston, MA
Region: Northeast
Topic: Shrubs
Title: Identifcation of strange orange growth on shrubs
Answered by: Nan Hampton

QUESTION:

I have found a strange orange ball shape with softer spikes about 1-2 in. growing from it on my shrubs, they grow around the branch. I believe they are Yews. I have never seen them before but now there are 2 baseball sized ones and a few starting. The bush was trimmed a week ago but they are growing a few inches into the bush. I do have a few pictures. PS they are located in Cape Cod MA

ANSWER:

This sounds like the fungal disease Cedar-Apple Rust (Gymnosporangium juniperi-virginianae) that is a serious problem for apples since it can defoliate the tree and affect fruit quality, but causes few problems for junipers and cedars except cosmetic ones. The orange structures with spikes are called telia and occur only on the cedars/junipers and produce spores that infect the apple host. The spores produced on the leaves of the apple infect the cedars/junipers. Here are more photos and information from Oklahoma State University, Colorado State University, and Cornell University.