Burning Bush with Thread Grafts

A client brought this tree into the studio. It was one of several Burning Bushes collected near a pond where the nutria that lived there nibbled on the bark and created deadwood.

Burning Bush, Euonymus alatus, before fall pruning.

Several years ago we noticed a hole in the design of this bonsai, on the right. We did a thread graft in that empty space. A thread graft uses a long supple shoot that is threaded through a hole drilled in the stock. (In another post we’ll cover the mechanics of thread grafting.)

Maple will often thread graft in a year. This Burning Bush took three.

Encouraged by our slow but eventual success, we tried a second graft in the same area. This one is going on three years and still hasn’t taken. Often when the grafted shoot isn’t as vigorous as hoped then fusing takes another year or two longer.

After pruning. Red arrows show the position of both grafts, filling out a hole in the design on the right side. The small branch coming off the root on the lower right may or may not be used in the future design, depending on how well the grafts do.

Here’s the first graft. The red circle shows where the long shoot was cut off after the graft “took”—which means the thread graft cambium joined with the stock cambium and a vascular tissue bridge was built. Here you can see that in the swelling at the base of the shoot to the left.

Another view of the same graft, the red line on the left where the shoot came from, now cut off.

Here’s our second graft. Once taken the grafted shoot will thicken where it exits the hole. This one has not yet done so. Once we see that we’ll cut off the opposite side in the growing season. This graft is identified with a red pipe cleaner so we don’t accidentally trim it. Letting it extend freely is the best way to make it take.