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.

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Sunday - November 30, 2014

From: Austin, TX
Region: Southwest
Topic: Invasive Plants, Septic Systems, Trees
Title: Does Acacia farnesiana (Huisache) have agressive roots?
Answered by: Nan Hampton

QUESTION:

Hello, Do you know if the Huisache tree has an aggressive root system? I have a few in proximity to my septic draining field and I need to know if I should cut them down to prevent clogging of the septic drainage lines. Your help is more than appreciated! Thank you

ANSWER:

There are two opinions for your question about Acacia farnesiana (Huisache) roots:

From the University of Florida IFAS Extension—"Roots: not a problem"
From Homeguides.SFgate.com—"Many acacia species have aggressive root systems...". However, they are mainly talking about acacia trees from Australia and they don't name Acacia farnesiana as one of the acacias with aggressive root systems.

Another source, an article, Choosing "Sewer Safer" Trees?" from the University of Tennessee Extension has useful information about planting trees that are "sewer safe". In their recommendations they advise planting more than 10 feet from sewer lines to minimize root intrusion. Although they do not mention Acacia farnesiana (huisache) as possibility (it is a native of the Southwest, not Tennessee), they do recommend planting a small, slow-growing tree to avoid problems with roots and sewer lines—the huisache does match those criteria.

From the Image Gallery

Huisache
Vachellia farnesiana