Hello

I have used zero near my natives without any ill effects. I am extremely careful though - the paintbrush is definitely the way to go. I probably wouldn't risk it actually underneath anything where leaves might brush against the weeds. I don't actually know how susceptible natives are to this sort of poison, but in my opinion it's not worth risking finding out, really. Hand weeding is probably safer in the tricky spots, bearing in mind that a lot of natives are pretty touchy about having their roots disturbed - ie don't dig around them.

Jen

I guess the question we have to ask ourselves whenever we put anything synthetic into the ground is 'what is the longterm result going to be ?'. That incldes fertlisers and things like wetting agents - I'm sure that its all good, but history has shown that Australians havent always had the facts in front of them with products such as DDT and superphosphate fertilisers. I dont have the science re Roundup/Zero, but the consensus seems to be that they are OK in moderation. I guess we'll really only know in 50 years or so. See link below for more.

And some tips:

http://www.mullum.com.au/wilsonscreeklandcare/weeds/weeds_techniques.html

Here is a link that might be useful: Effect of glyphosate on soil microbial activity and biomass

I have oxalis growing in my native garden and find the only way to get rid of it is by spraying it with weed killer. I've tried painting the leaves, but this seems to take too long to get to the bulbs, and, whilst this may kill a few, more seem to grow in the meantime.
I now use a wide necked plastic jar, (breakfast fruit type), with the bottom cut out. I place this over the oxalis, pushing the neck of the jar into the mulch and spray down as close as I can to the ground. If the oxalis is growing underneath a plant, I hold the plant out of the way with clothes pegs, leaving it that way for a few days.
I did lose a plant once when it rained soon after doing this. My garden is sloping, so I thought at the time that the rain could have washed the poison down through the ground. All other weeds I pull by hand, but doing this to oxalis just spreads it around even more.

I have runner type weeds as well that are absolute hell to try and dig up in clay soil but I'm still not willing to spray. Every weekend I pull up what I can see emerging through the mulch. If a large piece of runner comes up that's excellent, if not then I'm still weakening the plant - this is my logic anyway :). In nearly 3 years this particular weed has noticeably declined but is still a problem near one of the side fences. Perhaps not so funnily enough, that neighbour chooses to try and eradicate this weed in his garden with Roundup.

glyphosate is rapidly neutralised in soil (bacteria eat it quickly). The surfactants aren't, which was killing frogs. The most likely problem is spray drift and vapour drift, avoid spraying on windy days or very still days.

We extensively use glyphosate around Aust. native plants (both trees & shrubs) and it does an excellent job, along with the mulch.
I can weed 5 ac. of garden in about 2 hrs just by spot spraying out the weeds with a pressure sprayer with glyphosate. Overspray on the bark is not detrimental. Don't get it on the leaves though. As well I do the fencelines, and volunteer plants in the driveway.
However I buy it 20 litres at a time from the ag. merchandise store- about lesss than a quarter the price of those small packs from nurseries etc. One drum for $100 last for years.

Thanks everyone for all this advice. This forum has been a real help to me in this first attempt at native gardening. It's all looking good!

Glyphosate is only active to soft green tissue. The manufacturers claim it will not harm the plant if it has hard woody tissue or bark.
In most cases it is pointless spraying unwanted plants if it dormant or not actively growing. Also most weeds tend to be less suseptible when they have matured. Typically the most suseptible size for most weeds is when they reach about 100mm or so high.

You mentioned roses. This has been disputed before on GW but roses have many fine surface roots and weeds with similar roots mixed together with the rose roots, the roots are in contact with each other and translocation of the herbicide can take place. Glyphosate kills roots and all so it can kill the rose. This info was quoted to me a few years ago by a Monsanto representative.

Volume for volume Roundup is cheaper than Zero as Zero is only 100grams/litre against Roundup at 360g/l. There is even a stronger Roundup available.

Doug.

BE VERY CAREFUL with the Glyphosate!!!!
This product is forbiden to be sold in Sueden!!
Don't breath it,in Sueden,the have noticed,that you can get cancer,it's quiet dangerous for animals (pets),especialy cats,as they eat grasses,and lick their furs!
phil

phil, do you have any sources for this claim. Wikipedia has a very vague and unconvincing page at:
Glyphosate

Everything causes cancer it seems, the question is whether the cancer risk is higher from glyphosate/roundup than from say being out in the sun longer weeding.

For the record I work in a bush crew company and know a bit about weed control.

Now glyphosphate is great for killing weedy grasses/monocotyledons but, despite the false advertising, it is generally ineffective or less effective against broad leaf weeds/dicotyledons.

Now remember that plants with strappy leaves e.g. Dianella/Flax Lilies are, like grasses, monocotyledons and will be greatly effected by roundup.

It definately will do little or nothing to Soursob/Oxalis. For this weed and many others like it that have bulbs you need to use much stronger broad leaf/woody weed specific herbicides such as KambaM, Brushoff/Esteem or Garlon.

I recently checked up on regulations regarding these and it seems that, in Victoria, you are allowed to use amine formulations of these herbicides without an Agricultural Chemical Users Permit. But I recomend that these should be used with caution in terms of OH&S and environment. Painting preparations of these on to weeds would be OK as long as you wear appropriate safety gear.

Bearing in mind that glyphosphate does not work that well on docotyledons, most native shrubs are not greatly effected by small amounts of it. The foliage that is hit by the glyphosphate will obviously die however unless you some how accidently spray 100% of foliage it is highly unlikely that the tree or shrub will be killed outright.

If weedy grasses are the problem then you can use Fusilade which is a specific grass killer. Unless anyone out there knows of any exceptions, this can be sprayed over all dicotyledons, sedges and rushes. Ideal for a garden beds infested with couch or kikuyu. Not suitable for use near edge of water however.

For those who are a little intimidated by the above broad leaf herbicides I will add this...

The product Weed & Feed contains the broad leaf herbicide MCPA which we also use on a regular basis. The only problem with this product is that the MCPA does a good job at killing the broad leaf weeds in your lawn. However the fertilzer will then encourage a new crop of broad leaf weeds, particularly if the grass is struggling in hot dry weather.

Also products like Blackberry Kill, often available at Bunnings, will contain the same or similar active ingredient to that of the product Garlon.

We also use a lot of glyphosate around natives.

Use to:
* Kill large areas of kikuyu to prepare for replanting (typically 10 to 20 square metres at a time) and resprayed once or twice before mulcing an planting.
* Used every month or so with spray pack around native garden edge to stop grass ingress.
* Use in weed wand or by brush for oxalis and onion weed
* Used to kill persistent weeds like periwinkle, blackberry and privet - by brush on underside of leaves and also on stems after removing outside of stem with a scalpel.
* Used to paint on freshly cut stumps of privet etc

We buy generic undiluted 1 litre containers from Brunnings for around $8

We have never seen any negative affects on plants that could be caused by usage. But we are careful not to overuse.

Regarding translocation of Round-Up, you may find the published reviewed scientific research presented in the following thread to be of interest:

http://forums.gardenweb.com/forums/load/weeds/msg081647415766.html?24

Here is a link that might be useful: link for above