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Thursday - February 23, 2012

From: Austin, TX
Region: Southwest
Topic: Grasses or Grass-like
Title: Lawn fertilizer in Austin
Answered by: Barbara Medford


My lawn person wants to spread granulated spring fertilizer on my lawn. Problem is I have a very old Live Oak tree that I do not want to kill. What should I avoid spreading on my lawn to prevent toxic reaction for my beautiful Live Oak?


If this is "weed and feed," please, NO. Consider: there are two kinds of plant killers that can be included in a granulated fertilizer. One kills only monocots, which grasses are. The other kills dicots or wide-leaf plants. If you use the monocot killer, you will kill your grass. If you use the dicot killer, what kind of plant do you think that tree is? Right, a dicot, wide-leaved. Of course, many of the weeds in your grass are dicots, that's why that kind of herbicide is often used on lawns, but just consider how many other dicots that you have lovingly planted and watered are in the same area. Those granulated fertilizers, whatever is in them, will dissolve in the water of rain and sprinklers and be taken up in the water by the roots of the plants. The tree will use its vascular system to spread that chemical-laden water up through the entire tree. Sure, it may be a small amount in a big tree, but it also can accumulate. It might not kill the tree on the spot, but over time, it is not good for the tree.


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