I have no idea what that stuff is, but bet if it is 15 years old it's not going to be very strong or effective. What about just using some Roundup, if you absolutely have to to get rid of the grass?

If you had no problem with the grass in the area (nematodes, grubs, cinch bugs, etc,) I think I would skip fumigating. There are probably alot of good critters in that soil that would be harmed, so you might do more harm than good. Just my opinion. I pretty much try to stay as organic and non chemical as possible, so I admit that I am biased.

Thanks.

But as I said, if it doesn't work, no harm done (and see below). No, I don't believe Roundup is a good idea. Vapam chemically breaks down in the soil within a few days, while Roundup does not. I wouldn't plant anything where I've used a lot of Roundup for a month or two at least. Also, Roundup is a surface herbicide. It kills green stuff on top. I want to kill small roots and seeds down below.

As to organic and non-chemical, yes, I do that ... where it counts. In this case, I'm REALLY trying to kill stuff! I'm not trying to kill insect pests, but the grass itself. Especially the Bermuda. The cacti I plant there won't care about soil microorganisms, and those microorganisms and insects will reestablish themselves in a year or so anyway. Vapam is actually pretty safe in the environment, as long as it is applied properly. That's because, as I said above, it disappears completely in treated soil in a few days. I would never put it where it could run off into my creek.

So the issue is applying it properly. Instructions that have faded on my container.