Pruning Chinese Pistache (Keith Davey)
We have planted thirty ÂKeith DaveyÂ Chinese Pistache (seedless male clones) to meet our needs for a drought resistant, shade tree with easy clean up. Now, after one growing season, we are looking for pruning guidance.
The only information we could find on the internet was for pruning pistache propagated from seed, and it was very limited (attached at bottom), and wonder if it makes sense for our trees. And there is no one we could find in our area (Paso Robles, CA) that has experience with these trees.
WeÂd love to hear your suggestions on best pruning practices for our trees. Since some of the trees have multiple leaders (3-5), how many leaders would be best to remove at this time? At what length should we prune these leaders to force new branch growth? How do the dynamics of strong winds and the varied growth rates (see below) factor into the pruning decisions?
Some background info.
Last October we planted thirty 15 gallon trees. The trees came from the nursery topped at seven feet with 2 to 5 leading branches. None of the leaders were pruned off at planting time. These leaders were 1-2 feet long and clustered at the point (or very near it) where each tree was topped.
The trees are planted 4-6 ft. from the edge of a wide (10-12 ft.) pedestrian sidewalk with one and two-story condos on the other side. Because our location is very windy in the spring and early summer, the trees were double staked with the nurseryÂs trunk stake left tied to the trunk so the winds would not snap the trunk. With the strong winds some of the leading branches were torn offÂmajor bummer.
Varied Growth Rates after first year:
- Some rapid growing trees have leading branches 5-7 ft. tall with no other branching on them or the trunk.
- The medium growth trees have leading brances 3-4 ft. tall. Some trees have no other branches than the leaders. Other trees have small branches growing from the leaders.
- Slow growth trees with leading branches that only grew 6 inches or so, with no other branching or just a few small ones.
We appreciate any help you can share!
Internet pruning info. for pistache:
The tree needs special pruning and training in the early years to create branches in desirable places along the trunk. It often grows with few branches, or with branches clustered at one point on the trunk, if it was topped in the nursery. Pick one to be the trunk, another to be a branch and remove the rest. Allow the tree to grow taller and again top the unbranched trunk 18 to 24 inches above the first pruning cut to force branch development there. Build the tree in this fashion until a desirable structure with well spaced branches is achieved.