Marshall Dudley wrote:
Eggs Zachtly wrote:
Marshall Dudley said:


We have a steep hill which cannot be mowed. It is planted with
creeping junipers, and until they fill out, clover ground cover.
Lately crabgrass has taken over. Since it cannot be mowed, it has
the potential to overgrow the junipers and kill them by shading,
besides making the whole yard look horrible.

We purchased some crabgrass killer, that Ortho said would not harm
clover. Fortunately we did a test with it, and it kills clover
despite what Ortho said. Does anyone know of a herbicide which will
kill grass, but not kill clover?



You didn't say where you were located (and I'm too lazy right now to do a
trace), but crabgrasses are annuals.
Knoxville Tennessee area.
By the time you get enough treatments
down to be effective, it'll probably be dying anyway.
But if it goes to seed, we have the same problem next spring, but worse.
If you want it gone
now, yank it out.
Paid a bunch of Mexicans a lot of money to do exactly that about 2
months ago, this is new since then..
Next year, put down a pre-emergent, at the proper time,
and don't disturb the soil in that area all season, or you'll break that
barrier. There are millions of crabgrass seeds that will try and
germinate.
Most will be stopped by the barrier, but as each one pokes a tiny hole in
it, eventually some will get through. But, if you keep applying the
pre-emergent, each year, you'll gradually eliminate it.

Interesting idea. I am assuming that since clover is an annual,
pre-emergents won't bother it. You are talking about a barrier, but the
page I am looking at
http://www.landscape-america.com/pro...preemerge.html says that
it is:

"Preemergent herbicides are chemicals that prevent the germinating weeds
from establishing in the lawn. These herbicides control annual grass
weeds by inhibiting cell division in the young root system. The failure
of the root system to develop results in the death of the young seedling
weed shortly after germination."

So I am still a little confused. Are there two types, a barrier, and a
chemical that prevents germinating seeds from growing? And should
either work if so?

The preemergent is the barrier. I agree with advice given. In
addition, I believe crab grass killers are all arsenicals which I do not
like putting on my lawn.
Frank