The very first time I ever saw South Pasadena, more than twenty eight years ago, I was, of
course, in a car. Stuck in a traffic jam, desperate to make my way to Pasadena for an
appointment, I pulled out my Thomas Guide and figured that I might be able to exit the I-10 at Fremont Avenue and find my way north. Alhambra was much sleepier then, with narrower
streets and smaller buildings, but it was noticeable, even shocking, the visual line of
demarcation at Alhambra Road. Of course, the South Pasadena houses might have been a little older, and there were fewer commercial buildings, but the real difference was the trees!
All of my life before our move to Southern California had been spent in places with glorious mature trees- Michigan, England and New Orleans. When we first arrived in Los Angeles, we lived in Park LaBrea and there were certainly trees in the Mid-Wilshire area, but the delight I felt under a nearly continuous canopy driving in South Pasadena was something I had not experienced in our new home and which I did not forget. Seven years later, we were lucky enough to find a house here, and we are still happily in the same spot.
Living in an urban forest is a pleasure, but it is also a privilege and a responsibility. We have had the threat of the 210 Freeway extension and now we have a more subtle menace, a long term drought. To keep our trees alive and healthy, we all need to act together to protect and nurture them for our own benefit and that of future generations.
When Mother Nature cooperates and provides plenty of rain, our trees manage rather well on their own, but right now, after many years of inadequate natural water and government
mandated water restrictions, our trees are under threat. Since we derive fresh oxygen, a noticeably cooler microclimate and a tremendous boost to our property values in addition to the pleasure we get from the great beauty of our trees, it is time to take a good look at them and give a little back to help support them.
I spoke with Terry Chesboro, our great local South Pasadena resource and Certified Arborist to give us some guidance to help with the care of our trees. Most of what he recommends is not difficult, and will result in real and speedy benefit.
* Remove grass from under the drip line of your trees. When on a drought restricted watering
schedule the grass will actively pull water and nutrient from the tree roots, resulting in an even drier tree.
* Remove any rocks or gravel from under the canopy of the trees. This may look pretty, but it prevents free air circulation to the soil and roots and absorption of any water.
* Do not cultivate the soil under the drip line of the tree. It encourages the development and spread of the Phytophthora disease.
* In heavy clay soils, typically what we have in South Pasadena, apply garden gypsum to the soil.
* Lay soaker hoses in concentric circles under the canopy of the trees, starting about four feet from the trunk.
* Make sure the crown of the tree is not covered by soil.
* Spread a layer of mulch over the bare soil. Terry Chesboro recommends composted tree company mulch, sold by Cal-Blend Products in Irwindale. Composted mulch shrinks very little, protects the roots from the heat and sun, provides nutrient to the soil, fights Phytophthora and holds in moisture.
* Forget the blowers and keep all of your tree and shrub leaves to mulch your own trees. Add this every year on top of the mulch. As you would find in any forest, trees and shrubs like their own litter. It completes the cycle with very little effort or input on a gardener’s behalf!
* Water your trees once a month, overnight, with your new soaker hose. Terry suggests the use of the less expensive, black hoses that you can buy at OSH, because they have a slow dispersal rate.
* Take core samples after you have watered your trees the first time. Your soil should be damp to a depth of approximately eighteen inches. This will confirm the amount of time you should leave the soaker hose on.
* The following trees should be only minimally pruned. Pruning will result in permanent damage and disfigurement to the tree: Japanese Maples, Crepe Myrtles, Gingko, Camphor Trees and Jacaranda.
* Trees that respond well to pruning: Chinese Elm, Ash Trees, Carrotwood, Carob and Eucalyptus, especially Blue Gum.
* In general, no more than twenty percent of tree mass should be removed during pruning.
* Keep all garden strimmers away from the trunks of your trees, as they can girdle a tree very quickly.
Keeping our trees healthy and well watered will help them through the drought.
Sometimes we are in such a hurry that we don’t really observe the changes in the natural world around us, but a careful look at our surroundings will alert us all to the danger faced by our neighborhood trees. Don’t forget those in the parkways- they are the responsibility of the homeowner, and their care will pay us back many times over. Our urban forest needs a little help from all of us just now, and will reward us many times over.