how to get rid of thistles

Hey guys
Anyone know much about thistles and how to get rid of them once and for all .
The new cycle is starting for this yr now here and it seems to go from one veriety to the next right through until about march in the following yr . There's about 6 different kinds that come through one by one right through summer , we're on 7 ac's .
l've strated spraying the first lot but then l've just read that allot of the round up type sprays are related to agent orange - not good !
l have heard you can chop them out with a hoe before they seed but with 7 ac's , it would be nice to know if this worked before l went ahead .
Or maybe there are safe sprays that get rid of them or some other method someone knows of .
l sprayed them all as new ones come through last yr over about a 5 mth period [ my first yr here ] - heaps of work . But now already this yr they look like they'll be coming back just as bad plus l've only just read that bit on the agent orange thing .
lt could have been exaggerated l don't know , couldn't see it being aloud on the market these days if that was really the case but who knows !

Thanks for that.
Cheers
Mb

G'day Mb

The most effective way that we found was to dig them out before they seeded and put them in a pile and burn. You will need to do this for at least a few years as the seeds can lay dormant in the ground for a while.

You will never get rid of them as birds and other animals can spread seeds around as well.

On our old property which was around about 3000 acres, I would drive around on the old tractor with a trailer behind and just drive all over collecting them. The new property we have now is not as bad but they are there. We have pretty much got rid of them, but one or two will still pop its head up every now and then.

You just need to get on top of them and then its just a matter of keeping them under control.

Get a Horse to eat them. Probably wont solve your problem but is hillarious to watch.

G'day MB,
At our pony club we use Brush-off to get rid of broadleaf weeds. We have a problem with kahki burr that it's solved. Is expensive but a little goes a long way. We also add detergent (Holdfast) and a dye to see where we've been. If you have grazing animals you do not need to fence off poisoned areas. Dicamba is another one, but you need to fence off.
goodluck!
Cheers
Michael

Glyphosate is not related to agent orange and is not the preferred option.

As Michael said there are selective chemicals available to do the job without killing the grass. They also are not agent orange as they have no Dioxin.

David

Thanks very much for those guys and that ingredient to David l'll check the stuff l have got to make sure that's not in them first of all .
Hey DJ - Warrnambool , l'm at Port Campbell . You'd sure know all about the exact ones l'm asking about - 3,000 ac's , you poor bugar !
So did you find chopping them out was the best in the long run or ?

Cheers

I just use a shovel, I would just shove it into the ground a couple of inches from the base and just lever the whole rootball out. With a bit a practice you can have them out quickly