When I went to shut our last cooler off on July 18th, I discovered a bag with 5 varieties of pear scionwood. The scionwood would have been cut back in late February. All the scionwood was still green and viable. I decided to graft it onto a Moonglow pear tree. I took the pictures below tonight. As you can see in the pictures, all 5 grafts appear successful. It seems that as long as your scionwood is dormant and viable that you can top graft a tree long after it has broken dormancy. Fun experiment.