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Monday - August 08, 2011

From: Austin, TX
Region: Southwest
Topic: Watering, Trees
Title: Defining drip line on trees from Austin
Answered by: Barbara Medford


When you say that trees should be watered at the "drip line," do you mean that literally? I assume that the drip line means at the outside edge of the leaves or branches. Does that mean that watering closer to the trunk won't help the tree, even if the grass or plants underneath do benefit?


Sorry, we get so used to using certain catch words, we forget that not everyone speaks the same language. Watering anywhere around a tree during the kind of weather we are having is beneficial. When a tree is small and new, we recommend sticking the hose in the soil around the base and letting it drip slowly until water comes to the surface, at least twice a week. With a mature tree, not only would it be difficult to get that hose in there with all the roots, but there are roots extending far beyond that which need the moisture, too. Using the phrase "drip line" is just a quickie indicator, and not totally accurate. Remember that the roots of a large tree will often extend out a distance at least comparable to the height of the tree, which is usually much farther out than where the edge of the shade from the tree, or drip line, is established. Yes, run the sprinkler under the tree and not under the tree but still over the roots. The only caution we would make is to avoid getting the bark of the tree too wet, as this can invite fungi and diseases.


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