"Greg William" writes:
Every where I have put this "soil", heaps of onion weed has come up and is
thriving!

Flocks of sulphur-crested cockatoos descend on parks to pull up onion-weed
for its tasty onion bulb. You don't have a pet one you could train?

I have used roundup ,and ended up killing some other plants as well as the
onion weed

I believe I've heard Graham Ross (Ch 7) say that the only way to have
any success in getting rid of onion weed is to use an eye dropper and drip
a couple of drops of neat Zero straight down into the crown of the plant so
it runs into the heart and kills all the bulblettes in the cluster. Repeat
this exercise each Spring.
--
John Savage (my news address is not valid for email)