Q: I looked up the mimosa-like weed that was mentioned in your newspaper column and found it to be chamberbitter. It is all in my lawn and flower beds. Now that I know what it is, how do I kill it?
A: Chamberbitter (Phyllanthus urinaria) is a tropical weed that has become a major pest of lawns, landscapes and plant nurseries. Glyphosate (click for sources) will kill it but you have to be careful to keep the non-selective chemical off nearby foliage. In a lawn, broadleaf weed killer (click for sources) applied twice, seven days apart, is also effective.
I don’t know of an effective organic herbicide except hand-pulling.
The best way to control the weed is to prevent it. Apply isoxaben (click for sources) pre-emergent herbicide in March and again in early June to areas where you will not be planting seeds for anything else. As with every herbicide, read the label and follow it exactly.