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 dithiopyr (click for sources)pre-emergent herbicide in late April and again in mid-June to areas where you will not be planting seeds for anything else. As with every herbicide, read the label and follow it exactly.