On 5/31/2010 8:13 AM, Eggs Zachtly wrote:
Kate said:

Does anyone know what to use to kill Johnson Grass (a noxious weed)
in my lawn?


There's nothing I know of that you can purchase (as a homeowner), that you can
spray on Johnson Grass (Sorghum halepense) in established turf, that will kill
it and not harm the turfgrass.

Are you *sure* you've positively identified it as S. halepense? What color is
the midvein in the blade?

S. halepense spreads by rhizomes (making pulling the established plants next to
impossible), as well as seed (not letting it set seed will eliminate thst
possibility). It also prefers very wet areas. If this is the case, your best
recourse may be to remove all of the turf in that area (making sure to get all
of the rhizomes out), and re-grading the low area (or providing some other form
of drainage, such as a French drain). Don't just till the area, you'll end up
with possibly thousands of more plants (from segmenting the rhizomes). *REMOVE*
the infected area, completely.

Hi,

I should have given you more information.

I had a very bad case of Johnson Grass when I bought this home. The
first year I did not have time to deal with it. The second year I did
not know what it was, so I diligently dug each weed out by hand. little
did I know that the rhizomes spread like crazy and I was not
solving the problem.

I got two professional opinions and both told me it was Johnson Grass.
I killed 3/4 of my lawn with Roundup, which they recommended.
This is a five-year process. While I have reseeded, and am constantly
on this awful weed, I am gaining the battle. This will be my fourth
year fighting it.

The patches I killed last August - October are now filling in nicely,
however, come late summer, I know I will be spraying more areas.

What I do is hand paint the leaves of this stuff, and for the most part,
just the plant dies. But, there is some dead grass that has to be
reseeded the next year.

It does get better each year, but I was mostly reaching out to find out
if anyone else has had experience with this monster, and what they used
to fight it.

I also keep my lawn mowed very short, and I don't over water it.

Thanks, and sorry if I mislead you.

Kate