Host an Event Volunteer Join Tickets

Support the plant database you love!

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?

Share

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

Sunday - March 30, 2008

From: Austin, TX
Region: Southwest
Topic: Pests, Propagation, Trees
Title: Vehicle friendly oak trees for Austin
Answered by: Barbara Medford

QUESTION:

Do Chinquapins, Shumards or Live Oaks produce lots of tree sap? I'm looking for a vehicle friendly Oak tree to be installed in parking areas in Austin, Texas.

ANSWER:

Quercus fusiformis (plateau oak) is evergreen, while Quercus muehlenbergii (chinkapin oak), and Quercus shumardii (Shumard's oak) are deciduous. Actually, Live Oaks do drop a third to a half of their leaves, usually in the late winter, every year, but they are smaller and more easily dealt with, plus you have the advantage of the trees being green year-round, which you won't have with the others. All three trees are native to Texas and, therefore, good selections for Austin.

In terms of tree sap, almost all sap falling or dripping from trees is the product of insects, most often aphids. Generally, this aphid damage is not enough to cause problems for cars parked under them. There are other, more serious insect infestations that can cause sap to be exuded. The worst of these does not just cause irritating dribbles on the cars, but can quickly kill the tree. Of the trees you asked about, only Quercus fusiformis (plateau oak) is a live oak. Live Oaks are more susceptible to oak wilt than the others, which should definitely be a consideration in your choice. This link to the Texas Oak Wilt Information Partnership will give you some valuable advice on oak wilt. Please take note of the information on that site, and, if you decide to plant live oaks, to make sure the proper cultural practices are observed in caring for them.

By, the way, all oaks bloom in the spring, and put out a fine dusting of green pollen. Not only is this an allergen for many people, but it's also pretty irritating on paving, walks and cars.


Quercus fusiformis

Quercus muehlenbergii

Quercus shumardii

 

 

More Propagation Questions

Separate pups on Manfreda variegata in Tucson
July 20, 2009 - Can you tell me the best way to separate pups on a Manfreda variegata? The first ones we tried were very close to the main plant. Your help is appreciated.
view the full question and answer

Propagation of Blackfoot daisy seed
July 21, 2015 - I have a three yr old Blackfoot daisy. How do you root Blackfoot daisy seeds? When is the best month to grow these seeds?
view the full question and answer

What kind of alcohol to use with Passiflora seeds?
March 12, 2010 - Hi, I read a question and answer related to gernmination of passiflora incarnata. You recommended a 5% alcohol/water solution to soak the seeds prior to sowing. I just want to make sure that you are...
view the full question and answer

Propagation of Ashe junipers
June 04, 2008 - I am trying to re-build what man has destroyed in the Kingsland/Marble Falls area on a property we own out there. I would LOVE to plant a couple ashe junipers for several reasons, a couple being: 1. ...
view the full question and answer

Replacing hawthorn bush with muhly grass from Plano TX
April 10, 2014 - I am thinking of replacing a hawthorn bush with a muhly grass plant or two in an edged area with river rock cover in Plano, texas. It is the black soil and not a sandy loam. We have a sprinkler syst...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.