Datura said:


So, I've got at least 70% bermuda after 2 years, but in the areas where its
thin, I've got lots of henbit (I think). It's a short leafy plant with a
purple flower.


Perhaps it is ground ivy, not henbit? Henbit is a rangy annual winter weed with
(typically) pinkish-purple flowers. Pulling it out by hand before it blooms can
control it, as can fall applications of a pre-emergent herbicide. Keeping the
turf healthy, thick and growing through the fall is also preventative.

There's a pretty picture of a fallow field full of henbit in bloom he
http://www.psu.missouri.edu/fishel/henbit.htm

Ground ivy, on the other hand, is a perennial weed, worse in shady or semi-shady
areas (where the summer is hot), not easily controlled by pulling. The flowers
are more purple than henbit (sometimes blue-violet) and the bloom (in my area)
about the same time.

For some close-ups of ground ivy (and a mention of a couple of other weeds
it is sometimes confused with):
http://www.ppws.vt.edu/scott/weed_id/glehe.htm

I've got ground ivy in part of my lawn, henbit in the vegetable garden. Rarely
do I see henbit in the lawn, and it's easily pulled.
--
Pat in Plymouth MI

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)