Any experience with black locust

The DW wants to put some small walkways in the garden. Some of the stuff that grows in there winds up on people's dinner plates. I think those are tomatoes in the middle of this pic. The fence is white cedar.

http://farm7.staticflickr.com/6123/6...e942776d_b.jpg

The walkway will probably be mulch or wood chips. I need a border to keep that stuff in. Like to use a lumber. Pressure treated (PT) doesn't have arsenic anymore, but must be some other nasty stuff to keep the bugs away. And probably leaches into the soil over time. My local sawmill man has some black locust 2"X8"s in a bin. Was thinking about using that. Supposedly, when buried, black locust lasts about half as long as stone. It's a natural product, just grows like that, seems less likely anything leaches out of it. Actually, I checked it out a few years ago. The local building inspector told me that The State of New Jersey rates black locust for 60 years, buried, in the ground. So, that's the minimum.

Slightly off topic, but I also built an Ipe deck some years ago. I notice the bugs (gnats, mosquitoes and such) never come near it. Works for me.:rolleyes:

Any thoughts on the black locust in a vegetable garden?

Unique idea.

No, I have not used BL in that or similar manner. However, I've been told BL is used in the old gold mines of California to shore against cave-in. I've been told some BL shoring has been in the ground well over 100 years and is still very strong!

Very well could do exactly as you desire.

It would work well in that application.

black locust is hard, strong, and prone to twisting
rot resistance is better when used in log form ie, not split or milled
would work for your purpose as a garden plank

When used as a fence post it has a long life second only to hedge(osage orange). I would think that as lumber it would still do well just maybe not equal to being used whole as in a post.

There's an old story abt. B. Locust used as fence posts. Old folk said they had to move the fence every so often 'cause the ground rotted before the posts.
Well, I though it was kinda funny................
Bill