Opinions needed. I needed to remove a large viridis from a full sun location b/c it was outgrowing its space. In spring 2006 I trenched around it, cutting through some pretty big roots. I waited till fall to transplant it and it is thriving in its new location.
I had a beni hime in another sunny spot where it was doing great (likes full sun per Vertrees). I moved it to the spot where the viridis had been in May 2007 and it promptly wilted and died. We were in the midst of a bad drought which continued all summer and I chalked it up to the stress of this and some disruption of the rootball during the move. I bought another beni hime and planted it in the same spot in October 07, the drought now over. It leafed out vigorously this spring but after awhile I noticed its tiny leaves were wilting and it died a slow death. I dug it up today and the bottom of the rootball was very moist to wet.
My local nursery guy says it is probably a fungal root rot. Do y'all agree? Is it possible that the decaying roots left behind by the viridis was the initial substrate for an infection? Would you dare plant another JM there and if so, would you just replace the soil first or is there a product you would also apply to the soil? Sorry to be long-winded. Here's a picture of the first beni hime in happier days.
Unfortunately root rot is the most common cause for JM death in our area because of our heavy soil. However, fungal root rot usually takes a little while to come into effect. Usually drowning is quicker. It is possible that the tree could have already been infected with root rot, and because of the transplant the roots could no longer support the top. Phytothera (sp?) is particularly bad in my area, and it thrives in moist conditions. It however usually takes at least a few months to kill off a tree completely (usually one section at a time). Southern oak root rot however can be fatal in a quick period and is usually evident by sheets of whitish fungus under the bark of the base of the trunk and root crown. I personally wouldn't plant another there regardless.
I can't answer any of your questions but one ... and that is in square agreement with Matt...it is NEVER a good idea to replant in the grave of a former tree. I don't think you will ever know for sure what killed your tree maybe the second tree was infected with something the third tree got or maybe it was just coincidence or maybe that area isn't right for that beni ...the virdris is allegedly pretty very hardy strong tree ( I don't have one but it is a tried a true cultivar in this country)...and maybe that area was "ok" for it but not the Beni...you will never know that is why I would agree with Matt do not replant there ..David