Tree Of Heaven

Tree of Heaven or tree of Hell?

‘A Tree Grows In Brooklyn’ documents the resiliency and invasiveness of the common but typically undesirable tree of Heaven, Ailanthus altissima. Once a single female tree get established, the extremely prolific seeds get everywhere, including cracks in concrete. The resulting seedlings conquer wherever they are not dug out. If cut down, they just resprout from the roots.

Male trees smell horrible while blooming for about a month in spring or summer. They are pollinated by flies, so naturally smell like what flies like. The tiny yellowish or tan flowers hang on panicles that can be a foot and a half long. Female blooms are not as big, prolific or objectionably fragrant. However, stems, leaves and all other parts of both genders smell rotten when handled.

Tree of Heaven, which has earned the alternative names of ‘tree of Hell’, ‘stink tree’, ‘ghetto elm’ and ‘ghetto palm’, is no longer a tree that gets planted by choice. It is typically a tree that plants itself, and on rare occasion, happens to grow into a good situation. They should not be allowed to overwhelm more desirable trees, or get too close to concrete or other damageable features.

Young trees grow very fast to about forty feet tall. Older and slower trees do not get much taller, although sheltered trees can get twice as tall, with elegant gray bark. They do not live much more than fifty years. The big pinnately compound leaves are surprisingly pretty. On vigorous shoots, individual leaves can get as long as two and a half feet, with leaflets as long as six inches.


John the Baptist really knows carob.

The locusts that John the Baptist ate out in the desert were not grasshoppers. They were the nutritious locust pods of the carob tree, Ceratonia siliqua. Their familiar sweet cocoa flavor was probably fine for a while, but the starchy texture must have gotten dreadfully monotonous. After all these centuries, carob is still grown for food and as a shade tree.

It takes a very long time for a carob tree to get taller than forty feet. Most are less than thirty feet tall, and not quite as broad. Their rounded canopies are very dense. The stout trunk and limbs are quite sculptural, with variably but handsomely textured bark. The five or six inch long evergreen leaves are pinnately compound, with very glossy round leaflets.

Unfortunately, the big chocolaty pods are abundant enough to be messy if not harvested. Trees that do not produce pods bloom in autumn with seriously stinky male flowers that attract flies for pollination. Some trees are both male and female, so are both messy and stinky. Because carob trees are grown from seed, their gender can not be predicted.

Since they are from the drier regions around the Mediterranean Sea, carob trees really do not crave for much water once they have dispersed their roots. They grow somewhat faster if watered generously a few times through summer, but will survive without it. Too much water will cause buttressed roots that will break nearby concrete.

Watering Trees Is Still Important

Trees in lawns, even drought tolerant sorts, expect to be watered somewhat.

All the optimistic predictions of a rainy winter do not help with the drought yet. Nice warm weather only makes the garden even drier. Many of us have let our lawns dry out, maybe with plans to replace them later. Some have decided to replace lawn with artificial turf, hardscape or other landscape features.

The problem with this is that trees and other large plants that have dispersed their roots under the lawns are thirsty for the volumes of water that they had gotten while the lawns were well watered. They can survive longer than lawn does without watering, and will adapt to less water when they do get it, but they can not do without water completely.

It seems silly to water artificial turf or new decking, but it is sometimes necessary, especially for thirsty trees like willow, ash, elm and redwood. This is why some artificial lawns are outfitted with the original irrigation systems of the lawns that they replaced.

Drought tolerant trees, like certain oaks and most eucalypti, are more adaptable. Of course, those that were originally watered generously are greedier. Those that got only minimal watering may not notice if they get none at all. Regardless of their requirements, they all can be watered less frequently than lawns were, but should be watered generously when they do get watered.

Generous, but infrequent watering soaks into the ground better to satisfy deep roots. It is actually what most trees prefer. Lawn needs frequent watering only because the roots are so shallow. Generous, but infrequent watering uses less water not only because less evaporates from the surface of the soil, but also because less water gets used.

For example, watering weekly for 20 minutes is a generous volume of water, but is still less than watering for 15 minutes three times each week. It is only 20 minutes of watering compared to forty five minutes of watering.

Camphor Tree

Camphor trees have stout branch structure.

The best camphor trees, Cinnamomum camphora, are in parks and other spacious landscapes. Such trees have sufficient room for their broad canopies. Although they do not grow rapidly, they eventually get quite large, and perhaps too massive for confined urban gardens. Some of the older local trees are nearly fifty feet tall, and nearly as broad. They have potential to get much bigger.

Camphor trees excel as shade trees. Their light green or perhaps yellowish evergreen foliage is quite dense. Shade of groups of trees or large trees with low canopies inhibits the growth of lawn grass. Also, roots are likely to eventually elevate lawn or other features that are close to the trunks. Foliar canopies are billowy, but can be lopsided, especially in windy or partly shaded situations.

Trunks and main limbs of camphor trees are rather stout, and can be rather sculptural. Trees should be pruned for clearance while young. Otherwise, obtrusively low limbs can become prominent components of the canopies. The tan bark is distinctively checkered. It darkens handsomely with rain. All parts of camphor tree are quite aromatic. Frass from spring bloom can be slightly messy.

Shade Trees Adapt To Urbanism

Traditional shade trees get quite large.

Modern urban home gardens are shadier and more confined than older suburban home gardens originally were. Modern homes are both taller and closer together on smaller parcels. Fences are also taller to compensate for the minimal proximity of adjacent homes. Less sunlight reaches the ground. There is not as much space available for shade trees. Nor is there as much use for them.

Huddled modern homes are simply not as exposed to sunlight as older suburban homes were. Sunlight is more of an asset than a liability. Walls, ceilings and windows are so thoroughly insulated that shade is less important. Solar arrays up on roofs must remain exposed to sunlight. Smaller and denser trees are more important for obscuring views of adjacent homes, rather than for shade.

Shade trees are still useful for rural and suburban homes. Shade helps to keep older and less energy efficient homes cooler through warmer summer weather. If strategically situated to the south, west or southwest, they shade homes during the warmest time of day. Well proportioned trees do not darken too much of their gardens. Deciduous trees allow warming sunlight in through winter.

The popularity of modern urban homes is directly proportionate to the popularity of small evergreen trees. Such trees fit into smaller garden spaces, and permanently obscure unwanted scenery. Big deciduous shade trees that are practical for larger garden spaces become obtrusive in confined spaces. Defoliation in winter reveals unwanted views, and deprives the landscape of privacy.

Some of the more practical of small evergreen trees are actually large shrubbery. English laurel, Carolina cherry, photinia, hopseed bush and various pittosporums can get high enough to obscure neighboring windows. All are conducive to pruning if they get too tall. If staked on single straight trunks, or pruned to expose a few sculptural trunks, they do not occupy much space at ground level.

Tristania laurina, and some melaleucas are naturally small to midsized evergreen shade trees. Some species of Podocarpus can be pruned as midsized trees.

Himalayan Birch

The white bark of Himalayan birch is even more striking that that of European white birch.

Himalayan birch, Betula utilis ‘Jacquemontii’, must not be confused with the more traditional European white birch! If young trees get added to established groves of European white birch, they will never fit in. Their trunks stand vertically rather than lean casually. Their limbs are upright and angular instead of softly pendulous. Their bark is actually whiter.

Mature trees can get taller than thirty feet without getting much more than half as broad, and are relatively symmetrical for birches. The form of any single exposed tree is generally conical, although several trees together adapt to develop as picturesque groves with fewer interior limbs. The shade below is not too dark for lawn or moderately shade tolerant plants.

Maintenance is not exactly minimal. Vigorous young trees should be pruned and groomed annually, or at least every few years. Pruning should not be done in early spring when sap is likely to bleed from pruning wounds. Roots want to be watered somewhat regularly, even through the drought. When they fall in autumn, the two inch long leaves can be difficult to rake from fine gravel or bark.

Bigleaf Maple

A maple with unusually big leaves.

Its natural coastal range extends from the extreme southern corner of Alaska to the southwestern corner of California. Another inland range occupies foothills of the Sierra Nevada. Bigleaf maple, Acer macrophyllum, is the most common and prominent native maple here. However, it prefers the seclusion of forested riparian situations at higher elevations locally. It is rare in urban gardens.

Bigleaf maple is best in the wild anyway. It dislikes the aridity of most of the urban and suburban areas of California. (San Jose is in a chaparral climate. Los Angeles is in a desert climate.) Roots of bigleaf maple are potentially aggressive, especially if irrigated generously. They easily displace pavement. Nonetheless, where climate and circumstances allow, bigleaf maple is a grand tree.

Wild trees grow as tall as a hundred fifty feet within forests where they compete for sunlight. Well exposed suburban trees should stay lower than forty feet, while extending their canopies broader than tall. The big and palmately lobed leaves are mostly more than six inches wide. Foliage turns yellow in autumn, and is abundant as it falls. Self sown seedlings often grow under mature trees.

Bad Wine

I believe that this is a young Chilean wine palm, although I am not certain.

Italian Americans, particularly Californians, are expected to be experts in regard to wine. I am not. I can not explain it. I dislike wine, especially the best of it. It smells and tastes like rotten grapes. When I learned that Chilean wine palms were, and might still be, decapitated for the collection of their sap, from which wine is made, I learned yet another reason to dislike wine.

This little Chilean wine palm, Jubaea chilensis, pictured above, lives just a block or so away from the bad date palm that I wrote about last Sunday. No one here will try to make wine from its sap. The utility cables that seem to be too close in the background actually pass with plenty of clearance to the right, so will not be a problem in the future. This young palm should be safe.

Although I have encountered too few of the species in my career to be completely certain that this little palm is a well bred Chilean wine palm, it is very convincing. I see no indication that it is a hybrid of another species. About half of the Chilean wine palms that I encounter are hybrids. Most of these are hybrids of queen palm. Others are hybrids of pindo palm. Both look weird.

Of course, well bred Chilean wine palms are not much better. The specimen pictured below demonstrates that, regardless of how bold and striking they are, they are still rather weird palms. That is probably why they are so rare now. They were rare even during the Victorian Period, when weird species were trendy. Yet to many, their distinctive weirdness is part of their allure.

I can not help but wonder where this Chilean wine palm came from. Someone must really appreciate it to put it here.

Chilean wine palm is not a good houseplant.

Fine China

Before: There was not much hope for the Chinese maple underneath this mess.

It will be just fine. The Chinese maple that I mentioned earlier this morning sustained surprisingly minimal damage when part of a bay tree fell onto it. The situation initially seemed hopeless prior to the removal the heavy debris that was pressing the diminutive Chinese maple downward. Yet, the little tree somehow regained its composure, and is expected to recover.

The little Chinese maple was always rather sparse in the shade of the surrounding forest. Also, it exhibited an asymmetrically sculptural form. That is likely normal for the species within its natural environment, where it lives as an understory tree (within the shade or partial shade of larger forest trees). The distinctive form and open canopy were part of its allure.

As the debris was removed, most of the stems of the Chinese maple sprang back into their original positions. Only two major limbs were fractured and needed to be pruned away. Some of the minor twiggy growth was groomed in the process. The main trunk was somewhat destabilized, but not too detrimentally so.

It probably should be no surprise that the little tree was so resilient to the altercation. It is, after all, an understory tree. Within its natural environment, it likely contends with the same sort of abuse. Chinese forests are likely just as messy as forests here are. Gravity pulls all that mess in the same direction.

The little Chines maple may not look like much now that it has been groomed and pruned to be even more sparse than it originally was, but it should be fine. By this time next year, foliar density should be comparable to what it was prior to the incident. The form will remain sculptural, as it grows away from the shade of the forest, and out over the stream below.

After: After a bit of grooming, this little Chinese maple is not so badly disfigured.

Six on Saturday: Timber! III

At the end of May, Six on Saturday – Timber! II, ended with a precariously disfigured bay tree. Timber!, on May 10, mentioned that most of the tree had previously broken apart and fallen on top of a big Douglas fir tree that had fallen earlier. Prior to this big mess, the bay tree had been leaning on the Douglas fir tree. Now, it just continues to deteriorate. The precariously disfigured limb that remained last May was the most recent victim of gravity. Not much of the tree remains.

1. This was what we were concerned about. The disfigured and fractured trunk twisted from leverage exerted onto it by an upper limb, which is now extended downward instead of upward.P00718-1

2. Damage was impressively minimal. An exemplary specimen of Chinese maple sustained a direct hit from the main limb of the bay tree, but also sustained only minor structural damage.P00718-2

3. The trail somehow remained passable, although closed because of the big fallen limb dangling above. As the limb was dismantled, the fractured portion of the trunk broke away and fell.P00718-3

4. This big piece of the twisted and fractured portion of the trunk looks like a canoe, and is about as big. This was suspended more than twenty-five feet up, which is why the trail was closed.P00718-4

5. What remains of the bay tree is still severely disfigured, but is not so dangerously structurally compromised. It can remain until another arborist can get here to remove it and other trees.P00718-5

6. It looks worse up close. Nonetheless, there is not much we can do about it now. The limb to the far right originates from the same trunk. The big gray trunk in the background is a tan oak.P00718-6

This is the link for Six on Saturday, for anyone else who would like to participate: