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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.

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Monday - June 03, 2013

From: Austin, TX
Region: Southwest
Topic: Soils
Title: Asphalt beneath surface of soil in Austin
Answered by: Barbara Medford

QUESTION:

About 3-4 inches below the surface of our yard is what appears to be asphalt. It comes out in chunks a few inches across and it's all about 1.5 inches thick. I have no idea what it is; my best guess is that our lot was at one time a parking lot or something before it was developed into a subdivision. Other than just being a pain every time I have to dig a hole, will this cause any problems for my plants by leaching chemicals into the ground or anything like that?

ANSWER:

This is not a happy situation and we were unable to find any actual scientific studies on the question, but we did find a couple of forums. You need to remember that forums are the expression of opinions on the part of whoever writes in, and not necessarily scientific fact. However, here are links to those forums:

Garden Web

Fine Gardening

Our opinion is that it was illegal to leave this material in the soil, and should have been caught in inspections of the property, but we are gardeners, not lawyers. You might try contacting the Texas A&M Agrilife Extension Office for Tarrant County to see if they have any information. As gardeners, we would not want to plant anything, especially anything edible, in that soil and consider it contaminated.

 

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