Is Your Tree Due For Some Pruning?
How often should your tree or bush be pruned?
Short Answer: It depends… but typically every 2-5 years.
You might be wondering; “why would my trees NEED pruning? Nobody prunes trees in a forest, they seem to be doing fine…”
And you’d be right… forest trees don’t need to be pruned, but that’s because they’re raised to behave themselves… literally. The forest environment has been finely tuned over millennia to naturally influence and promote healthy and stable tree growth. Largely with the help of neighbouring, community, and parent trees. Trees are also able to self prune in a forest environment, by restricting resources to unproductive branches, and allowing the environment to dislodge the weakened limbs. This process can however take year, and creates a dangerous area around an unkempt city tree.
Lacking this influence and restraint, urban trees living high on the hog with unlimited resources (namely; space, light, and air) quickly grow into unsustainable shapes and sizes, which lead to disease, injury, poor fruit, and even premature death.
TIP: Want to plan a yard that requires little to no pruning? Stick with "columnar" tree varieties. These are trees specifically bred to maintain a well behaved, uniform shape. Conifers such as a dwarf spruce or fir are also a great, low maintenance choice.
So when should you prune your tree to maximize its natural vigour, health, and beauty? That depends primarily on two factors.
1) tree type (size, age, species)
For the sake of simplicity, we can break urban trees into three categories; large, ornamental, and fruit bearing.
Large trees: This is going to be your big stately elms, maples, ashes, birch, linden, poplar, and willows. Though these trees should be monitored for signs of instability; they’re generally going to do fine with a pruning every 4-5 years to remove dead wood, thin the canopy, and remove excess horizontal weight.
Ornamental: This is going to be any tree that maxes out around 20′. Primarily; mountain ash, Amur maple, mayday, and lilac. These trees generally pose less of a safety risk due to their size, and so pruning is primarily focused on tree health and aesthetics. They do however tend to over take the area, since once they reach their maximum height, they continue to grow horizontally for the duration of their life. Every 4-5 years is typically adequate to keep them happy and under control.
Fruit Trees: Fruit trees tend to have much more specific needs, especially if you cultivating with the intent to harvest the fruit. If left to their own devices for too long, they will begin to over crowd, resulting in too much vegetation, very poor fruit quality, and an ideal environment for fungi and pests to colonize. Its generally advisable to prune your fruit tree every second fall, or every 3 years at most.
Visible signs or disease or decline are often best addressed with pruning as a first resort. Things like; dead wood, growths, signs of pests, splitting joints; should be identified and pruned as soon as possible to minimize the long term tole on the tree.