After a year, I finally did it! I didn't want to but felt it had to be done. You may recall, after the 2013-2014 winter, the English Ivy that covers the walls of the tunnel took a major beating. I was encouraged by the new buds I saw breaking on many of the vines but it never did make the comeback I expected. The south side of the tunnel is recovering just fine. However, I cut all of the dead off of the North side and replanted Ivy plugs at the base of the wall. It will take some time, but it will be back. This surprised me given the agressive nature and invasive growth habit of this plant!