What to Know About Some of My Favorite Trees in the Park – Orange County Register
Freesia (Photo by Joshua Siskin)
I have recently received emails regarding two of my favorite trees: Eucalyptus and Victorian Box. When considering my favorite tree species, four characteristics come to mind: a symmetrical, dome-shaped canopy, glossy leaves, an evergreen growth habit, and scent. Colorful flowers, as beautiful as they are, are not enough for a tree to hold a place in my heart.
Consider the pink trumpet tree (Tabebuia rosea). It is one of the first – if not the first – trees to bloom in the new year, even before winter is over. While still leafless, there is an explosion of yellow-throated pink trumpets that glow with their beauty for a month or so before wilting. Don’t get me wrong. It is as stunning a tree as you can imagine in bloom, and is an excellent candidate for a street tree due to its medium height and narrow stature. However, for at least ten months of the year, there is not much to look at at this tree, nor does it produce the soothing and reassuring feeling of lush permanence that my favorite trees evoke.
And here I must declare my preference for fairly large trees. It is suitable for most residential yards but may be too large for some. Yes, I know that large trees are more expensive to maintain than small trees. However, I suppose that when I think of these trees, I consider them in their ideal state – that is, how they look growing with plenty of room around them, and so much space that pruning is rarely needed. Sometimes we forget that the main reason to prune a tree is because leaving it unpruned could cause damage if a branch breaks. When it comes to the possibility of broken branches or fallen trees in a storm, nearby structures, vehicles parked underneath, and passing pedestrians are always a concern. In urban and suburban areas, trees should be inspected annually by a certified arborist and pruned regularly because breakage often occurs when trees receive more light on one side than the other — which they often do — due to their proximity to homes or other buildings. Furthermore, when trees are installed in tight spaces or planted too close together, poor air circulation as pruning is not done regularly can lead to insect and disease problems. However, in their original state, when developed as individual specimens with plenty of room to grow on all sides, trees that in populated areas rarely survive more than a century or even half that long, may last for a thousand years.
Take the camphor tree (Cinnamomum camphora) for example. I received an email from Rob and Sharon Friedrich, who garden in Lomita, about a wonderful specimen growing in a nearby schoolyard that is estimated to be between 60 and 65 years old, and appears to have reached the mature height of eucalyptus trees, which is 50 years. -60 feet. While eucalyptus trees may live up to a thousand years in their native Japan, they often do not live more than 50 years in the United States. The tree in question at the top has shriveled and looks like it may be in a downward spiral as all the new growth has died and Rob and Sharon don’t remember this ever having happened before. Their tree may benefit from watering with a deep-rooted irrigation device. This device is a perforated metal rod with a pointed tip that is sunk into the ground. You attach a hose to the top of the rod and water flows down and out through the holes. You move the watering device around the tree, soaking each area as you go, so that the entire root zone is saturated. The drip line or perimeter line of the tree’s canopy is where you want to water because this is where feeder roots grow that consume water and minerals most actively. Root waterers range from 24 to 48 inches in length. Although almost all of the water a tree needs is absorbed by the roots growing just a few inches below the soil surface, having a reserve of water below will benefit these shallow roots as they move upward into the soil through capillary action.
This device is recommended when soil compaction is an issue. Even with all the rain we’ve received this winter, if the soil can’t absorb the water due to compaction — perhaps from children moving around the schoolyard over the years — it won’t reach the roots below. You can find root watering devices online for $30 to $40. On the other hand, there is also the possibility that this tree is suffering from Verticillium wilt, a fungal disease caused by excess water in the root zone, a condition that may have been triggered by last winter’s heavy rainfall. In such a case, it may be helpful to mix liquid fertilizer with the water flowing into the root irrigation device. A deep watering device with fertilizer spreader sells online for $40. Finally, water only when the soil around the tree is dry to a depth of three inches.
Eucalyptus trees are blessed with luminous foliage that appears pink, turns bronze, and eventually acquires a greenish-yellow luster. The flowers are fragrant, if barely noticeable, and the leaves give off a camphor odor when crushed. Birds consume black fruit voraciously. The bark is deeply furrowed and turns dark black when it rains. Although some people consume the young leaves, the leaves and mature fruit are definitely toxic, and I would not eat the young leaves either unless I was directed in their consumption by an expert in foraging the eucalyptus tree.
From a distance, the Victorian Box (Pittosporum undulatum) can be seen and is a distinctive tree due to its glossy green leaves and domed canopy. Unfortunately, it is susceptible to Victorian box decline, a disease whose origin is unknown, but may be attributable to compacted soil, too much or too little water, and/or pathogenic fungi. It grows quickly at first, eventually reaching 40 feet in height but with a lifespan of only 40 years. It produces a fragrant cloud of white flowers in spring and, in time, orange fruit containing red seeds. Although it usually grows as a tree, it is also used as a hedge or as a screen. Lisa Hubert, a gardener in San Francisco, points out that this type of tree may have an allelopathic or toxic effect on plants growing in its vicinity, and asks for suggestions on what might grow under it. Regardless of toxicity, some discourage planting anything under a Victorian box due to its susceptibility to root disturbances. However, since Hubert has a plant box under her tree, it is probably safe to plant shade-loving species in it. I suggested using shade-tolerant succulents — aeoniums, echeveria, and jade plants come to mind — because of their low water requirements and shallow roots.
Before I leave the topic of my favorite trees, I should mention the Persian lilac or Chinese mulberry (Melia azererach). This tree gem It may evoke strong emotions in both active plant lovers or gardeners and armchair plant watchers alike. Chinaberry (Melia azedarach) has two qualities common to trees that tend to make you catch your breath and stand in silent awe: lush foliage and a perfectly domed canopy. Even in drought conditions, Chinese Mulberry maintains a fresh, vibrant appearance, requiring only a moderate dose of Los Angeles winter rain. The Chinese mulberry plant grows quickly to 30-40 feet in height and makes beautiful shade trees. Its purple flowers have the scent of a grape-flavored soft drink. Unfortunately, this tree is rarely seen in the nursery trade. Because Chinaberry grows so easily, it has gained a reputation as a weed even though it does not grow out of control in our area and is not found on California’s list of invasive species. Although not found in nurseries, its seeds germinate easily and are widely available through online sellers.
California Citizen of the Week: Goodbye Spring (Clarkia amoena) is perhaps the most widely distributed native wildflower of California worldwide, with the exception of the California poppy of course. Its cup-shaped flowers are usually various shades of pink, but sometimes lavender as well. The name “Farewell to Spring” does not refer to when it blooms, but rather to when it stops flowering, as the arrival of hot weather indicates its disappearance. The botanical name Clarkia honors William Clark who, with Meriwether Lewis, discovered what would become the western United States. Rosemary (Clarkia unguiculata) is a relatively worthy plant, especially its varieties with double flowers that look like small pink, red and purple roses decorated on red stems. I have seen self-sowing rosemary on Parkway strips in several locations throughout Los Angeles.
What are your favorite trees and why? Tell me about them in an email to email@example.com. We always welcome questions and comments regarding any garden issue or gardening practice, as well as gardening tips and photos.