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 - August 08, 2011

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Are Ashe Junipers dying from mite damage in Austin?
Answered by: Barbara Medford

QUESTION:

If Ashe Juniper needles are turning brown and dropping off the trees because of drought, and not disease, do the needles ever come back, or have the tree limbs died? What if the cause is mites, not drought? If the needles will come back, how do you tell if a limb is dead, and not just temporarily bare?

ANSWER:

We have been hearing from all over North America on the subject of members of the Conifer family, including Ashe Juniper, suffering from mite damage. Here is a previous answer that pretty well sums up what we know about this problem, with associated links.

Various Problems of Ashe Juniper

In terms of whether the needles will come back or is the branch dead, we can't be sure. The needles that dropped off have done so because of the heat and drought. If the branch survives, they will put on new needles, because they are the "leaves" of the juniper and are needed to provide nutrition to the plant. If you want to determine if a branch is dead, try the thumbnail test. Scratch a very small sliver off the branch with your thumbnail. If there is a thin layer of green beneath that out covering, that branch is still alive.

The mites are actually taking advantage of the stressed tree. If the tree were not suffering so much they would replace the needles lost to the mites, and you wouldn't notice the damage. It would appear that the best thing we can do is wait for rain. If you have just one tree and you are concerned that it has mites, you can turn a hard spray of water on it, which will wash the mites off. They will come back, but not so quickly. If you have 30 acres of junipers, this is hardly practical; again we have to let Nature take its course.

We would advise waiting until the weather has cooled and (hopefully!) there is some rain before you make any decisions about trimming dead limbs.

From the Image Gallery

Ashe juniper
Juniperus ashei