Horridculture – Tree Preservation Ordinances

Padding should protect these London plane street trees from minor altercations with machinery that will be used to demolish the associated buildings and construct new buildings.

Much of my work involves inspection of trees to assess health, stability and structural integrity, and subsequent composition of associated arborist’s reports to document such assessments. These reports are necessary for the issuance of permits to remove mature trees within many municipalities. They are only effective for that purpose if they recommend and justify removal.

If there is nothing wrong with the health, stability or structural integrity of subject trees, removal might be justified for other reasons. For example, the removal of superfluous trees might be justified if it would promote healthier development of remaining trees. Trees that disperse roots that are beginning to damage adjacent infrastructure might likewise need to be removed.

It seems like it is too much to be concerned with for something that property owners should not need permission to remove from their own property. For what people pay for property here, they should be able to do whatever they want to with it. However, mature trees are considered to be assets to their respective Communities, and components of the collective urban forests.

These majorly and justifiably controversial concerns are actually not the the only difficulties associated with municipal tree preservation ordinances.

While a young coast live oak in the extreme corner of my garden was not quite big enough to require a permit for removal, I asked the next door neighbor if he would like it to be removed before the roots damaged his driveway. I explained that if we waited any longer, the tree would be protected, and that a permit to remove such an exemplary tree would not likely be issued.

Tree preservation ordinances are often the motivating factor for the removal of trees before they get big enough to be protected! I was fortunate that my neighbor wanted my oak to stay.

California Pepper Tree

00101It has been naturalized in Southern California long enough to seem to be native. California pepper, Schinus molle, is actually endemic to Peru and adjacent arid regions of South America as far south as Central Argentina. Furthermore, although its small pink fruits with hard black seeds are sometimes used for culinary purposes, it is actually not related to black pepper, and is mildly toxic.

California pepper is as at home here as the name implies. Established and naturalized trees can survive on annual rainfall. They are better foliated if watered a few times through summer, and do not mind average landscape irrigation if their soil does not stay too damp. When they are not dropping a few leaves, they are dropping floral frass or dried berries, so their mess is considerable.

Old trees can eventually get forty feet wide, and almost as tall. Young trees grow rather aggressively. Growth slows with maturity. The distended and irregularly structured trunks and main limbs are picturesquely gnarly, with handsomely flaky tan bark. Foliage and outer stems are delightfully pendulous. The pinnately compound leaves are finely textured, and about three to six inches in length.

Growing Problem

P91221KRecycling plant material is practical and gratifying. We do quite a bit of it here. Back in September, I briefly wrote about recycling laurustinus that was removed from an area that was about to be landscaped, and relocated to other sites where it can grow into functional informal hedges. We were able to use something that was a problem in one location as an asset somewhere else.

We will be doing more of this sort of recycling now that the rainy season has started. Right now, the plants that need to be removed are as dormant as they get, so do not mind getting dug as much as they would have while they were still active. Rain helps settle them in at their new locations. A few get canned and stocked into the nursery, to be planted into new landscapes later.

Some of what gets recycled was intentionally installed in the past, but for one reason or another, became inappropriate for a particular site. For example, I will soon be relocating agapanthus that performed well for many years, but eventually became too shaded by growing trees nearby. Forsythia that has already been relocated was too big and awkward for its confined space.

Many plants that get recycled were not intentionally planted, but happened to grow wild in situations where they can not stay. Some are native. Some are descendents of desirable exotics. The laurustinus that I mentioned above are such an example. Just yesterday, I relocated a few naturalized but superfluous birches from an established landscape to an unlandscaped area.

We certainly do not recycle everything that can be recycled. Many plants, both native and naturalized exotic, are just too problematic. Fleabane that I wrote about yesterday is marginal.

Sweetgum happens to be one of those trees that we probably should not recycle. They are splendidly colorful in autumn, and particularly spectacular amongst the deep green redwoods. The problems are that the now overgrown trees here are developing serious structural deficiency, and producing an overwhelming abundance of messy and potentially hazardous maces (fruits).

Nonetheless, I found and canned these four rooted sweetgum watersprouts. They were growing from roots of one of several big and very problematic sweetgums that got removed last year. If they get planted here, they and their associated problems will be located outside of refined landscapes. In the future, thy can drop maces and limbs in the forest without bothering anyone.


41217Climate is why the European larch, Larix decidua, is so rare here. It prefers cooler weather in both winter and summer, and more humidity. Foliage can roast if too exposed through summer. Small trees that are partly sheltered or partly shaded by larger trees have the best color and foliar density. Larch are innately reliant on somewhat regular watering, so are not drought tolerant. The mildly cool weather of autumn is enough to brown the formerly bluish foliage, which falls shortly afterward.

In the wild, larch trees can get as tall as other big coniferous trees. However, the many different garden varieties stay much smaller. Some are very pendulous. A few have contorted stems. Of the few that can sometimes be seen locally, most are compact dwarfs that grow more like low and dense shrubbery than trees. Some get only two or three feet tall and broad, and grow very slowly. These can stay in containers or planters for many years.

Blue Spruce

91225For a tree that is native to the upper elevations of the Rocky Mountains, blue spruce, Picea pungens, does surprisingly well here. It only wants to be watered a bit through summer to compensate for the lack of rain and humidity in chaparral climates. It does not seem to miss a more pronounced chill through winter. Disease and insect infestation are uncommonly noticeable or damaging.

Garden varieties are impressively variable. Some are like big shrubbery that stays below downstairs eaves. The biggest do not get much taller than thirty feet, and take many years to get so tall. Most but not all are stoutly conical. Color is variable as well, ranging from grayish green to silvery bluish green. The evergreen foliage is very dense. Individual needles are only about an inch long.

Blue spruce demands patience, planning and room to grow. Pruning for containment compromises their naturally appealing conical form. Therefore, even compact cultivars that do not need much space will need enough to mature completely. However, because they grow somewhat slowly, blue spruce may take a few years to actually occupy much of their space, and function as intended.

Spruced Up

P91214KSpruce happen to very compatible with the landscape style here. They fit in nicely with surrounding redwoods, but are more proportionate to sunny spots of some of the refined landscapes. We intend to add a few into some of the landscapes as they get renovated. They will stay branched to the ground, like big dense shrubbery, with the personality of distinguished forest trees.

Several dwarf Alberta spruce, which is a very compact cultivar of white spruce, have been incorporated into landscapes that were renovated during the past few years. They really are dinky though, and stay smaller than most shrubbery. Some of the very compact cultivars of blue spruce that we would like to add next will eventually get significantly bigger, but do not grow fast.

A few spruce that grow more like tree rather than shrubbery would be really excellent. The taller blue spruce with more open branch structure are no longer available from local nurseries, but could be ordered. I particularly want to try any of the white, black, red, Engelmann or Sitka spruce that are endemic to North America, although I know some might not be happy here.

Sitka spruce just happened to become available. A colleague brought these eight seedlings back from the coast up near the Oregon border, and will probably get a few more. They are prolific there, and get pulled like many other weeds. At the rate they are growing, they could get planted into a landscape even before we get any blue spruce! I am already very pleased with them.

For a while, I grew each of the six North American spruce, but only in cans. Since these Sitka spruce arrived, I have been wanting to get the other five. White spruce is ‘sort of’ here. Blue spruce will arrive soon enough.


41210One might surmise that a tree that is resilient enough to be the state tree of Texas is not too discriminating. If it can take the heat and humidity of the Lone Star State, it can make it anywhere! However, pecan, Carya illinoinensis, actually prefers heat and humidity, and is bored with the mild local climate. The nuts and the mess that comes with them are actually less abundant than they would be in the Gulf Coast States. The deciduous foliage is not quite so colorful in autumn.

A mature pecan tree may stay a low as fifty feet, or get twice as tall. The height is usually nearly double the width. Generous watering can cause roots to buttress and displace nearby pavement. Most local pecan trees that are intentionally planted are garden varieties that were bred for bigger pecan nuts. Seed grown trees tend to produce nuts that are nearly comparable to the nuts they were grown from. The pinnately compound leaves have nine or more leaflets that are about two or three inches long.

Horridculture – Bad Guys

P91211Roots hold up trees. That is part of their job. They grow along with the trees they support, and disperse as necessary to maintain stability. Trees grown within the confinement of cans (pots) or boxes, and then installed into a landscape, are typically staked temporarily until their roots adequately disperse and stabilize. Once unnecessary, stakes and bindings must be removed.

Mature palms that get relocated are supported temporarily by guy wires. They are just too big to be supported by stakes. Because palm trunks to not grow any wider as at they grow taller, they are not damaged by the sorts of bindings that would damage the fattening trunks of other trees. Like stakes on other trees, guy wires must be removed as they become unnecessary.

Although they can be appropriate in unusual circumstances in which stakes would not be practical, guy wires are rarely used on trees that are not palms. Mature trees that get relocated can be guyed if too big to be supported by stakes. Because trunks and limbs of such trees expand (circumference), it is more important for guy wires to be remove when they become obsolete.

As useful as guy wires can be, they are more often used improperly or inappropriately. Firstly, those who install them rarely do so correctly, with the wires or cables as straight as possible between each end. Cabled anchors are usually pounded into the ground perpendicularly to the direction of the cable, so that the cable merely slices through the soil when tension is applied.

Once installed, cables are very often left in place long enough to constrict the growing trunks or limbs that they are attached to. Cables that apply too much tension or limit the motion of the trees they support (in the breeze) for too long will actually inhibit root dispersion. Trees will only become as stable as they need to be. Besides all this, lingering cables are just plain unsightly.

The cabled trees in these pictures demonstrate another set of problems that should be corrected by simple and necessary pruning, and comparably necessary adjustment of the automated irrigation. Guy wires should most certainly not be necessary for such mature trees of this species, and will interfere with necessary root dispersion without remedying the primary problems.

Firstly, the trees are too low and dense. Even if stability were not a concern, they should be pruned for a bit more clearance above the patio to the right of the picture, and perhaps allow a bit more sunlight to the plants below, even if only temporarily. More importantly, pruning would temporarily decrease weight and wind resistance of the canopies while roots adapt accordingly.

Secondly, the landscape is getting irrigated too much, even for the ferns in the background. This maintains soil saturation so that stabilizing roots can not disperse into deeper strata. Roots that might have extended deeper earlier will drown and rot. Until this happens, excessive irrigation promotes heavy superfluous growth that the compromised root system can not support.

Automated irrigation should be disabled for winter, and operated only manually and minimally if the weather stays dry long enough for the ferns to get drier than they are comfortable with. It can be adjusted accordingly when reactivated in spring. Even before that happens, and roots disperse, the guy wires can be removed as soon as these trees get pruned as they should be.P91211+

Italian Stone Pine

P90102Even though it can get about fifty feet tall and wide, Italian stone pine, Pinus pinea, often gets planted as a small living Christmas tree into confined urban gardens. It gets so big so fast that it can get to be a serious problem, as well as expensive to remove, before anyone notices. It is really only proportionate to large public spaces such as parks or medians for big boulevards. The bulky trunks typically lean one way or another. The long limbs spread laterally to form an unusually broad and flat-topped canopy.

The paired needles are about four to six inches long. However, small living Christmas trees are still outfitted with juvenile foliage that looks nothing like adult foliage. Juvenile needles are single, very glaucous (bluish) and only about an inch or an inch and a half long. Adult foliage may not develop for a few years. The four or five inch long cones mature slowly for three years. Squirrels and birds like the big seeds, which would otherwise be known as pine-nuts if people could get them first.

(Apologies for this inadequate illustration of Italian stone pines damaged by traffic. It was the only picture of Italian stone pine I could find.)

Christmas Trees – Dead Or Alive

41203thumbChristmas trees are like vegetables. Really, they are like big vegetables that do not get eaten. They are grown on farms, and then harvested and sent off to consumers. Although they smell like a forest, and they are descendents of trees that naturally grow in the wild somewhere, there is nothing natural about their cultivation. In fact, most are grown a very long way from where their kind are from. Therefore, bringing a cut Christmas tree into the home takes nothing from the wild, and does not interfere with nature any more than eating vegetables does.

Firs, particularly Douglas fir, are the most popular of Christmas trees. Pines are probably the second most popular. Redwoods, spruces, cedars, cypresses or even Junipers can also work. They each have their own distinct color, texture and aroma. Healthy and well hydrated trees that continue to get watered as needed should have no problem lasting through Christmas. Ultimately though, cut Christmas trees are not good for much after Christmas, and eventually get composted or otherwise disposed of.

Living Christmas trees might seem like a better option to cut Christmas trees because they dispel any unfounded guilt associated with cut Christmas trees, and initially seem to be less disposable. The problem is that they have problems of their own. Simply purchasing one is a big expense. Even the big ones are smaller than cut trees, but much heavier and unwieldy. Contrary to popular belief, only a few types that grow slowly, such as some spruce, can actually live in a tub for more than one or two years, and even they can be finicky.

The main problem is where to plant a living Christmas tree when it outgrows its container. Conifers innately do not like to be confined for too long. Yet, in the ground, most grow into substantial trees. The common little Christmas trees that are already decorated are actually the worst since they are juvenile Italian stone pines or Canary Island pines, which grow big and fast. Potted trees can not be planted out in the wild because their confined roots need to be watered until new roots can disperse. Even if they could survive, non-native trees should not go into natural ecosystems.