Sometimes trees in the orchard don’t do as well as Farmer Al hopes. There are plenty of difficult decisions a farmer has to make for the greater good of the farm. And one such decision is giving up on an underperforming crop and adapting. Farmer Al did just that when he converted some of our Robada apricot trees to grow Rojo apricots instead. And he did that with a magical process called grafting.
A tree has many parts. And one of the most fundamental of those parts is the rootstock—the underground part of a tree with traits that make it grow well in a particular region’s soil. When grafting a tree (adapting it to grow one fruit variety instead of another), you want to keep the rootstock of the original tree and build upon how well the tree is already adapted to its environment.
Grafting is a much different process than planting a whole new tree. When you graft, you cut off a lot of the original tree, but not all! You take a stick from the chosen variety that you want to change the tree over to, and you wedge that stick into a notch you’ve made in the original tree. This little stick, which has the genetics of the new fruit variety, is called scion wood.
After you insert the scion wood into the wedge, you paint it over with a sticky substance that prevents air from getting into the open cut. That allows the tree to heal and adopt this new wood as a part of the whole.
You don’t leave the scion wood to grow all on its own, though. The farmer leaves a branch from the original tree to help it along. We call that a nurse limb. If we didn’t leave that, if we cut all the original branches off, the rootstock would send too much energy (in the form of sap) into the tiny scion wood and push it right out! In addition to absorbing some of that energy from the root system, the nurse limb also shields the scion wood from the wind.
Farmer Al and team did this apricot grafting last winter. A couple weeks ago, they saw that there was plenty of growth on the scion wood so the team could remove the nurse limb. The grafted parts of the tree can absorb the energy from the root system all on their own now. In about 2 or 3 years, the tree will be producing fruit that we can harvest!