Last year I purchased a Shawl (at least I hope, since it was not labelled) through ETSY from a Southern California dealer. It arrived in two days, but one of the branches was shriveled and black. The dealer asked me to wait for two weeks, but at the end of one week, the rest of the branches had turned black (except for a branch on the root side of the graft, which I cut off. This is not the point, since the dealer issued me a full refund.
After I had the bare trunk, I removed it from the nursery soil and dipped it in fungicide. I did not bother cutting away any roots because few remained intact. I replanted the plant in a mixture of sandy loam and lava rock, and gave it a few treatments of hydrogen peroxide. About three months later, in the middle of the California winter, it started forming leaf buds, and it now has leaves.
My question is this: if the plant recovered, is it safe to plant in my garden of should I be aware that I may be introducing the fungus to my soil? Originally, this was meant to be planted in a compact arrangement, with two trees about 18" apart on a mound (based on the method described by R. Frost in "Planting an avocado tree or two"), but that has changed since the tree was received in poor condition and also I found an Epicenter blog post that Shawil is not a preferred variety for Northern California. So, it will probably be planted on a different property on a mound by itself. Or, should I just keep it separated in a pot? Or, even though it looks like it recovered, should I discard it? Or, I guess the safest thing would be to attempt to graft it to a healthy tree?