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Tuesday - July 07, 2009

From: San Antonio , TX
Region: Southwest
Topic: Trees
Title: Distance of oak tree to existing driveway in San Antonio
Answered by: Barbara Medford

QUESTION:

How close can I plant a live oak tree (15 gal) next to an existing driveway. I have about 3 feet space to plant between a fence and a driveway. This is the best spot to provide future shade. My concern is if the roots will raise the concrete over time.

ANSWER:

An oak tree root system is extensive but shallow. The ground area at the outside edge of the canopy, referred to as the dripline, is especially important. The tree obtains most of its surface water here, and conducts an important exchange of air and other gases. Any change in the level of soil around an oak tree can have a negative impact. The most critical area lies within 6 to 10 feet of the trunk. No soil should be added or scraped away from that area. Paving should not be in the dripline and no closer than 15 feet from the tree trunk. The area around the trunk-at least a 10 foot radius-should be natural and uncovered.

Not only would your pavement begin to buckle, but the tree would not thrive, either. What is on the other side of the fence? The tree roots can go under the fence, but then is there another driveway or foundation? We would hate to see you go to that much trouble and expense planting such a large tree, and have it cause so much trouble down the line and probably lose the tree, too. Now that you know what kind of spacing the tree needs, perhaps you can find another place on your property where it will be able to grow without disruption of foundations, sidewalks, driveways or its own roots.

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Tuesday - July 07, 2009

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