"Dave Gower" wrote in message ...
"Bishop Don Magic Juan" insertnamehere.co.uk wrote

...Must wait at least seven days for Roundup to do
its work. Tilling a few hours after application competely nullifies the
purpose of Roundup.

No. If that were the case then Roundup would be rendered ineffective if it
rained or there was a heavy dew any time within a week after application.

Any type of herbicide (selective or universal) requires a few hours to soak
in. It then takes a week for the plant to die. This will happen whether the
soil is turned over or not (except of course that turning the soil over
increases the damage).

Read the instructions on the bottles. It explains it all.



It's true that Roundup works by absorption. However, if the soil is
tilled within a few hours, the roundup will not be distributed
throughout the plant. Tilling will chop off the sprayed parts of some
of the weeds, leaving the lower part and root system unaffected.
Waiting until the weeds are dead is the correct strategy. BTW, what
is the big hurry anyway.

Some of your other advice is wrong too, like telling him not to use
crabgrass killer or weed killer next spring. That is just plain
wrong. A lawn that is planted now should have pre-emergent crab grass
preventer applied next spring and also spot weed control as needed.
Neither of these products is harmful at that point and it's completely
consistent with the label directions.

Do you even know the difference between crabgrass killer and
pre-emergent products? Failure to control crabgrass or weeds next
spring is a prescription for disaster.