Posted on by tonytomeo · 4 Comments

Streets Are Cooler With Shade

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Parked cars stay cooler in shade.

There really is no such thing as a perfect tree. Some are not quite as messy as others. Some have better structural integrity than others. Some have gentle roots; and some stay proportionate to tight spots. However, without exception, all trees grow, drop leaves, and disperse roots.

This is an important consideration when selecting any tree, and especially when selecting a street tree for the narrow space between the curb and the sidewalk (which is commonly known as a park strip). Even where there is no sidewalk, or where the sidewalk is at the curb, most of the obstacles are the same.

Street trees should have reasonably complaisant roots that should not be likely to damage curbs, sidewalks or roadways, at least for several years. They should naturally develop reasonably high branches. They will need to be pruned higher than trucks that may park at the curb. Street trees must also tolerate harsh exposure.

Wider park strips can of course accommodate larger trees. Those that are only two feet wide or narrower are probably not wide enough for any tree larger than photinia, purple-leaf plum or English hawthorn, which are difficult to prune for clearance over roadways and sidewalks.

Messy leaves, flowers or fruit that might not be a problem within the garden might be more of a problem at the curb. It is not so easy to rake such debris if cars park over it. Trees that are commonly infested with scale or aphid are likely to drop sticky honeydew (scale and aphid poop) onto parked cars.

Unfortunately, those who get street trees do not always get to select them. Many municipalities assign specific trees to specific streets. Some streets have a few trees to choose from. Others have only one option. Home Owners’ Associations (HOAs) decide if and where new trees get planted.

Crape myrtle is probably the most common choice for a new street tree because the roots do not get big enough to damage pavement. However, the canopies are not very big either. They stay too low to be pruned above trucks. Crape myrtle is susceptible to scale infestation that can get bad enough to make sidewalks sticky.

For many years, London plane (sycamore) had been another popular street tree. Unfortunately, the voracious roots can damage pavement within only a few years. The messy foliage discolors and starts to fall before autumn.

Posted on by tonytomeo · 6 Comments

Multi Trunk Trees Seem Natural

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Overgrown shrubbery becomes multi trunk trees.

For several years in the late 1960 and early 1970s, European white birch were trendy. Most lived in ubiquitous groups of three. Where three did not fit, a single multi trunk tree, typically with three trunks, was a popular option. Each multi trunk tree provided as many trunks as a few single trunk trees. For these particular white birch, the elegant white trunks were their most appealing feature.

Multi trunk trees, which are popularly known as ‘multis’, are only structurally different from their counterparts with single trunks. Multi trunk crape myrtle are genetically identical to crape myrtle of the same cultivar, but with single trunks. The only difference is that multi trunk trees branch at ground level, instead of at the top of a single straight trunk. Each needs to be pruned to the desired form.

Multi trunk birch, paperbark and lemon gum exhibit appealing bark. More trunks display more bark than single trunks. Multi trunk strawberry tree, olive and oak exhibit appealingly sculptural form. Cork oak and crape myrtle provide both appealing bark and sculptural form. Silk tree, acacia and deciduous magnolia display their bloom more effectively with lower and broader multi trunk form.

Trees get help to develop into a desired form. European white birch, lemon gum and silk tree are more likely to develop single trunks naturally. Coppicing compels them to regenerate with several trunks. Conversely, olive, crape myrtle and strawberry tree develop a few trunks naturally. Single trunk trees need thinning to remove the superfluous trunks, and staking to straighten a single trunk.

In home gardens, multi trunk trees sometimes evolve from overgrown shrubbery. Pineapple guava may be shrubby for may years before lower growth gets pruned away to reveal sculptural trunks within. English laurel that gets too overgrown for containment pruning might become a delightful multi trunk tree instead. It will be pleased to grow freely from the top if lower growth gets pruned off.

Multi trunk trees are no more natural than trees with single trunks are, but they seem to be.

Posted on by tonytomeo · 9 Comments

Timber!

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This is a bit more than just slightly inconvenient. The trail continues forward from here, with another trail up the stairs to the right.

It is that time of year. Warming weather accelerates vascular activity, which makes foliage heavier. If evapotranspiration is inhibited by humidity and a lack of wind, the foliage can get too heavy to be supported by the trees that produce it. All that increasing weight can bring down big limbs or entire trees at the most unexpected times. The process is spontaneous limb failure.

By ‘unexpected’, I mean that it happens when there is no wind. It is startling because broken limbs and fallen trees are typically associated with wind rather than a lack of it. Gentle wind actually accelerates evapotranspiration, which relives affected vegetation of some of its weight and susceptibility to spontaneous limb failure. Aridity helps too, by absorbing more moisture.

Of course, even a gentle breeze at the wrong time can have disastrous results for vegetation that is already about to succumb to spontaneous limb failure. I suspect that is what happened here, since the air was not completely still at the time. It was just a bit warmer than it had been, and slightly more humid than typical. It is too late and pointless to analyze the situation now.

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This is the top of the stairs that are to the right in the picture above.

At about noon on Thursday, someone who works nearby alerted me to the sound a a big tree falling. I was in the same neighborhood, but was driving by with the radio on. The tree is precisely where I was told it would be. No one was nearby when it fell. Damage was originally minimal, with a portion of trail displaced by roots, and a rail on a bridge crushed by the trunk.

By ‘originally’, I mean that this was not the extent of the damage. After barricading the trails and road leading to the site, and leaving, we heard another loud crash from the same location as a bay tree that had been leaning against the already fallen fir tree collapsed in pieces on top of the whole mess. Fortunately, the damage to the bridge, although worse, is not too terribly bad.

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There is more timber here than lumber. The short section of main trunk is severely fractures. The double trunks beyond are not as big as they look.
Posted on by tonytomeo · 16 Comments

Grande Finale

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They still bloom spectacularly.

This is the third spring that I got picture of this pair of flowering cherry trees in bloom. I took several pictures last year, ranging from closeup pictures of the flowers, to pictures taken from a distance like the picture above. Fewer pictures were taken during the previous spring of 2018, before these trees were groomed of copious necrosis. Sadly, this picture will be one of the last.

The trees will be cut down this year. They stayed just long enough to bloom this one last season, but will not likely be here much longer. They are deteriorating at such a rate that if I were to prune the necrosis away after bloom, there would not be much remaining. The tree to the right in this picture would be only a rotten stump with a few limber twigs protruding from the top.

Structural integrity has been so compromised by decay that, even without the weight of all the limbs that have been pruned back during the past many years, the trunks could easily break off at the ground. When I remove them, I will likely just push the tree to the right over without cutting it first. If there were any branches left, a kid could knock it over by trying to climb it.

As much as I would prefer for these trees to last much longer, I want to install their replacements as soon as possible. Planting them this spring would give them all summer to disperse roots and grow a little bit before blooming next spring. I know they will not be much to look at for a few years, but many years from now, they might be as spectacular as these two originals were.

Regardless, it will be a saddening task to cut down these distinguished trees.

Posted on by tonytomeo · 8 Comments

Alien

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It really looks like something erupted from within!

That was a scary movie back when horror movies really were scary! The first appearance of the baby alien was the creepiest part and one of the scariest scenes! It is too disturbing and gory to describe here. Those who have seen it may have noticed how it might seem to be weirdly relevant to the cavity that opened in the rotting trunk of this deteriorating flowering cherry tree.

With a bit more distance, the rotting trunk looks sort of like an associate of ‘H. R. Pufnstuf’ after an interaction with a baby alien. If you can remember who H. R. Pufnstuf was, you probably shouldn’t. He starred in his own television show for children on Saturday morning in the 1970s. It was disturbingly weird and perhaps even inappropriate for the children it was intended for.

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So, it is both rotten and unsightly.

With even more distance, it is obvious that this is nothing to joke about. This is one of two flowering cherry trees that I have been so protective of, and put so much work into temporarily salvaging. Both should have been removed and replaced years ago. This project was scheduled for after bloom in 2018, postponed until after bloom in 2019, and has yet to be done even now.

The problem is that these trees are so popular and so appreciated by the Community. They have been here in the most prominent spot in the neighborhood for several decades. There are not many who remember when the trees were young. No one seems to remember before the trees were here. They are as historical as the older buildings. I can not bear to cut them down.

As you can see, there is no choice now, at least for this particular tree. It is already so decayed that it can barely support its own weight.

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As pretty as the bloom is, the disfigured branch structure and trunk are no longer appealing.
Posted on by tonytomeo · 3 Comments

Deciduous Fruit Trees Need Pruning

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Dormant fruit trees will bloom soon.

Deciduous fruit trees have no business in a low maintenance landscape. They need as much specialized pruning while dormant in winter as roses need, and on a much larger scale. Neglected trees get disfigured by the weight of their own fruit. Disease proliferates in their thicket growth that develops without pruning. Overgrown trees produce most of their fruit where no one can easily reach it. Fruit that can not be harvested attracts rodents.

Of course, deciduous fruit trees are certainly worth growing if they get the specialized pruning that they need. Pruning concentrates resources so fewer but better fruits develop. Fruit bearing stems are better structured to support the weight of their fruit, and lower so that the fruit is easier to reach. Pruning also promotes more vigorous growth, which is less susceptible to disease and insects.

Now that it is February, and the weather has been unusually warm, deciduous fruit trees that have not yet been pruned will need to be pruned very soon. They will be sensitive to such major pruning once they start to bloom. The pruning is too specialized to explain here in just a few sentences. Fortunately, Sunset publishes an very detailed book about “Fruit Tree Pruning” that explains how to prune each of the different fruit trees. Pruning will be more extensive each year as trees grow, but also becomes more familiar.

Stone fruits like apricots, plums, prunes, nectarines and peaches (that have hard seeds known as stones), need the most severe pruning. Their fruit develops on stems that grew last year. These stems should get cut short enough to support the weight of the fruit expected to develop next year. The ‘four Ds’, which are dead, dying, damaged and diseased stems, should get pruned out as well. Cherries and almonds do not get pruned as much because their fruit is so lightweight; and out-of-reach almonds simply get shaken down anyway.

Apples and pears are pomme fruits that need similar pruning, but also produce on stunted ‘spur’ stems that should not be pruned away. Spurs may continue to be productive for many years. Figs, persimmons, pomegranates, mulberries and grapevines all need their own specialized styles of pruning.

Posted on by tonytomeo · 14 Comments

Horridculture – Skipping Ahead

January 17 is as far as I have gotten with the backlog of articles from blogs that I follow. I am now two and a half weeks behind schedule. Articles are old news by the time I see them. I have been trying to catch up for weeks or maybe months, but have instead been getting farther behind. The video above is from the article I posted back then. There has been no rain since then.

The video also looks like what I feel I am doing to that backlog of article while I skip ahead to current articles beginning with February 5. Flushing them like this seems so negligent. I feel so obligated to read the articles of blogs that I follow. That is why I follow them. However, if I do not flush the backlog, articles that are current now will also be old news by the time I get them.

I have been reading some of these blogs so regularly that those who write them sometimes include notes to me within the contexts of their articles. Sometimes they comment on something that they think I would be particularly interested in. Sometimes they ask questions that they think I might know the answers to, or just ask for a bit of advice. Flushing all that is just wrong.

I have no choice. I have no time for it all. I write my brief gardening articles for more small newspapers than I can keep track of. I still work at a part-time and temporary job that involves maintenance of landscapes and small scale arboriculture because I can not bear to leave! I intend to eventually return to work at nursery production, but have been too overworked to do so.

Meanwhile, former clients and clients of former clients continue to contact me in need of services that I can no longer provide. I can find no one to refer them to for comparable services. All of the best arborists and horticulturists are retired, deceased or too busy (compensating for the lack of those of us who are retired or deceased) to accommodate more work. It is saddening.

On top of all that, I am supposed to be canning cedar trees and plugging sycamore cuttings for street trees in Los Angeles a few years from now . . . and maybe working in the garden?!?!

Posted on by tonytomeo · 5 Comments

Pollarding Is Extreme Tree Pruning

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Pollarded knuckles look like science fiction.

Most arborists insist that pollarding is horticulturally incorrect. However, most of us who pollard trees in our home gardens are not arborists. Pollarding is technically detrimentally disfiguring to trees. However, some trees that are naturally short lived can live much longer if pollarded properly. That is the trick; doing it properly. Pollarding is certainly a distinctive pruning style that is not for everyone, but can be both practical and sustainable in certain situations.

Pollarding is an extreme pruning technique that involves the removal of all or almost all of the stems that grew since the last time the technique was done. The new growth gets cut back cleanly to distended ‘knuckles’ that develop at the ends of the original stems. Traditionally, one or two strategically aimed stubs from the removed new growth are left on each knuckle to form a new knuckle a bit beyond knuckles of the previous year. Locally though, stubs are typically omitted.

New growth must get cut back cleanly so that the wounds can get compartmentalized (healed over) as efficiently as possibly. Stubs interfere with this process. If one or two stubs are left on knuckles to form new knuckles, they should be long enough to get some distance from the original stubs, but short enough to not be too awkward. Knuckles should not get cut off! Such large wounds do not compartmentalize fast enough to avoid rotting.

Pollarding can only be done in winter, both because plants are dormant, and also because the weather is not so dangerous. New growth starts to shade exposed bark before it gets scalded by intensifying sunlight and heat in summer. Once they come out of dormancy, plants would be seriously distressed by such severe pruning. Because new growth is so vigorous after pollarding, it can become sloppy if pollarded less than annually. Some plants that grow slowly or produce stout stems may get pollarded less frequently.

London plane (sycamore) and fruitless mulberry are the most commonly pollarded trees. Silver maple, silk tree and various elms, willows and poplars adapt well to pollarding as well. Locust and purple leaf plum can be pollarded, but will be deprived of bloom. Bottlebrush can bloom later in the same year after getting pollarded, and probably will not need annual pollarding anyway. Pollarded bay trees can be kept small, and will provide better herbal foliage. Certain eucalyptus can be kept juvenile if their juvenile foliage is more appealing than their adult foliage.

Posted on by tonytomeo · 11 Comments

Horridculture – Tree Preservation Ordinances

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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.

Posted on by tonytomeo · 3 Comments

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+