THE TREE that stands in front of Mishkon’s sanctuary belongs to the City of Los Angeles. Like our sanctuary’s own façade, it is something of a landmark: it’s the largest shade tree for 1½ blocks in any direction — and the least-mutilated one.
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| February 2022 |
It needs pruning approximately every 2 years. Although the City is responsible for tending it in theory, in practice that’s not practical, due to the strained City budget: “The current tree pruning cycle is approximately 15 years,” says the website of the Bureau of Street Services, Urban Forestry Division. Hence during the past decade, Mishkon has several times arranged for the pruning of this particular tree.
It is now slated to be pruned by a certified arborist on Thursday, June 9. This post discusses the maintenance needs of “our” street tree.…
Happily, this Ficus tree (reportedly of the microcarpa species) gives solid shade and is hardy. Furthermore, it can be quite handsome if tended well. Granted, such trees are no longer approved for planting by the City because they eventually heave the sidewalks, are not power-line friendly, and do not support other species in their vicinity. Yet as Noël Johnston of the organization Verdant Venice wrote to me:
Practically any fully grown tree is to be preferred to a newly planted “shorty” which will take years to do the heavy carbon lifting that your tree does.… We would recommend that you encourage your tree to live a long life and, when it expires, replace it with a native tree and give it an underplanting.
What’s Our Authority to Care for This Tree?
According to the City, “Property owners may prune street trees at their own expense by obtaining a no-fee tree prune permit.” At the same time, there are standards that must be followed: “The City has formally adopted, and enforces, the International Society of Arboriculture (ISA) Pruning Guidelines and the American National Standard Institute's Pruning Standards (ANSI 300).”
A permit can be obtained almost instantly online HERE.
Diagnosis and Prescription
Here’s what the Certified Arborist told me when we met out front in early April:
This tree has been over-pruned [see below], which then resulted in an excessive growth spurt in reaction, in order to restore its natural ratio of root to branch.
Recommended treatment: Raise the crown [see below], and remove internal lateral branches, so as to open up the interior, enabling viewers to look through the branches. These steps will encourage the tree to flourish upward, away from the desired sight line, while encouraging the tree to restore its optimal root/branch ratio.
The pruning should wait until mid-June, after the normal spring growth spurt. That way, the impact of the pruning will last longer. The next expected pruning should be done in a little more than a year, as an interim measure — as part of helping the tree to recover from its history of mistreatment. Thereafter, about every two years.
Raising the Crown
“Raising the crown” means pruning the lower branches that extend from the trunk, while preserving the tree’s natural structure and increasing the distance that the canopy is above ground level. Here’s an example from a block in Santa Monica.…
What Exactly Ought to be Done?
Because pruning can be done in various ways, it’s important to be explicit about our goals. Here is what I requested from the pruning services that I spoke with, given the present situation:
1. Provide clearance so as to minimize conflict with desired line of sight (from portico at top of steps down Navy St. to ocean).2. Restore the natural growth patterns following damage from substandard pruning.3. Improve aesthetics (thinning).
What Ought NOT to be Done?
A common pruning practice in the L.A. is to top the tree. Topping is “the reduction of a tree’s size using heading cuts that shorten limbs or branches back to a predetermined crown limit.” However, according to the Tree Care Industry Association, topping is not an acceptable practice, for it can injure trees. Topping also tends to be more expensive in the long run, according to the International Society of Arboriculture.
As you can see from this image from Feb. 2020 (shortly after the most recent pruning in Nov/Dec 2019), it appears that our street tree was indeed mistreated the last time around. The crown was cut back to a predetermined size:
General Guidance
• How Much Should Be Pruned?
Generally, no more than 25% of the crown should be removed at once, and less for mature trees.
• When to Prune
As a rule, growth and wound closure are maximized if pruning takes place before the spring growth flush.… Heavy pruning of live tissue just after the spring growth flush should be avoided, especially on weak trees. At that time, trees have just expended a great deal of energy to produce foliage and early shoot growth. Removal of a large percentage of foliage at that time can stress the tree.
[At first glance, the above seems at odds with what the Certified Arborist advised for our street tree. However, his advice took into the account the fact that Ficus trees are unusually hardy, and that our short-term goal is more to minimize its growth than to maximize it. His advice is like that of this tree care web page:]
Summer cuts reduce the amount of food your tree gets by removing their food production source: leaves. Less food slows growth and forces your tree to focus on the most important areas. In addition, summer pruning enhances your ability to shape your tree because it is much easier to locate problem branches and areas.
Don’t Wait Too Long
One thing that I learned from my research is that we waited too long to give this tree the attention that it needs. It requires regular pruning. By waiting maybe 6 months too long, we have let things get a bit out of hand.
Who is Qualified to Prune?
1. A licensed tree service contractor.
See the Contractor State Licensing Board website HERE.
2. A Certified Arborist (CA)
Certified Arborists have over three years of documented and verified experience, and have passed a rigorous written test from the International Society of Arboriculture.
Selecting the Right Arborist for the Job
See guidance from the ISA HERE.
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