| 1. | Select the threading branch and entry location for graft. |
| 2. | Secure the threading branch by wiring the branch towards the entry location |
| 3. | For drilling the hole, only use a sterilized brad point drill bit |
| 4. | Select a brad point drill bit that is slightly larger than the width of the branch and buds |
| 5. | Though not essential, try to make the exit hole higher than the entry hole |
| 6. | Drill the hole from the side you want the branch to grow. Take care not to drill too fast. This will heat up the bit and thus damage the cambium layer. |
| 7. | The threading branch will enter the hole from the opposite side that the hole was drilled. That is, push the thread branch through the hole from the rough exit drill point to the cleaner entry point |
| 8. | Locate the best bud that is close to the entry hole. |
| 9. | If any buds end up with in the tree trunk, temporarily remove the thread branch and get rid of these buds |
| 10. | With bud and branch location set, scrape the bark off the lower sides of the branch so the cambium of the thread and the trunk meet. |
| 11. | Form a small piece of wood and insert it on top of the thread branch. This plug creates pressure and will help to establish cambium layer contact between the trunk and the branch. |
| 12. | Trim off any wood plug piece excess |
| 13. | Cover the hole and plug with cut paste |
| 14. | Wire the branch into an upward motion |
| 15. | Do not remove any of the buds from the outside or finished threaded branch |
| 16. | It is OK to remove buds from the thread inside of the branch |
| 17. | In a year or two, the threaded branch should become established. At this time, it is safe to severe the thread side once the new branch is equal to or larger than the thread |
On 02/21/10, bonsai expert Alan Taft gave a demonstration on the techniques of thread grafting. This technique is used to attach new branches where they are missing on a tree. The basic principal of thread grafting is that a hole is drilled through the trunk and an existing branch is then bent over and threaded through the hole. It is then fixed into position and given time to set into its new location.
Success is recognized when the branch cambium layer becomes integrated into its new trunk setting and it successfully foliates. At that time, the threading side of the branch is cut.