Limb Failure Of Spontaneous Nature

Riparian trees notoriously shed limbs spontaneously.

Winter storms sometimes break limbs or topple trees. Such damage is no surprise during winter because that is when almost all windy weather happens here. Early storms during autumn might be more damaging because deciduous trees are less aerodynamic prior to defoliation. Nonetheless, falling trees and limb failure are typically associated with wind.

That is why spontaneous limb failure is such a surprise when it happens, typically during pleasantly mild or warm weather of spring or early summer. It is more likely without wind than with it. Humidity, although atypical here, is a contributing factor. Healthy trees within riparian situations or lawns are more susceptible than distressed trees in drier situations. 

Particular types of trees are more susceptible to spontaneous limb failure as well. Valley oak, coast live oak, sweetgum, carob, some pines and various eucalypti may shed limbs after an unusually rainy winter or an increase of irrigation. Riparian trees, such as willow, cottonwood, box elder and sycamore are notorious for shedding big limbs unexpectedly.

Spontaneous limb failure occurs if limbs are unable to support their own increasing foliar weight. Bloom can add significant weight too. Warmth promotes the vascular activity that increases foliar weight. Humidity and insufficient air circulation inhibit evapotranspiration (evaporation of foliar moisture), which typically compensates for increasing foliar weight.

As the terminology implies, spontaneous limb failure occurs suddenly, and often without warning. It is therefore potentially very dangerous. It is common among limbs that exhibit no prior structural deficiency. Even experienced and educated arborists who are familiar with vulnerable tree species can not identify and mitigate all potentially hazardous limbs. 

Arborists often suggest pruning to limit the weight of trees that are innately susceptible to spontaneous limb failure. However, limbs that are already sagging from their own weight are risky to engage. Most damage occurs in spring and early summer. Fruit trees that are too productive can succumb to the weight of fruit as it ripens through summer or autumn.

Sculpture

This article from three years ago definitely conforms to the ‘Horridculture’ meme for Wednesday.

Tony Tomeo

P71206

I use the term loosely. Okay, so maybe I use it mockingly in this context. This sort of thing really should have no connection to the works of Calder, Rodin or Brancusi. It might be worthy of a few fancy adjectives, such as ‘severe’, ‘unusual’, ‘dramatic’ and ‘bold’. Horticulturally though, we might be thinking more like ‘disgraceful’, ‘abhorrent’, ‘ridiculous’ or ‘just plain sad’.

There is nothing wrong with pollarding, that severe sort of pruning that almost all other arborists will tell you is wrong. It involves pruning trees back to the same distended terminal knuckles every winter. Only a few trees are adaptable to the technique, and technically, sweetgum happens to be one of those few trees.

The stipulation is that once pollarded, they MUST be cut back to the same knuckles EVERY winter. A small stub or maybe two can be left on knuckles to allow them to elongate…

View original post 470 more words

Green Roof

This artice is from three years ago too, and the picture is a bit older. I sort of wonder if this tree is still there.

Tony Tomeo

P71125Is this a bad idea for a green roof?

Is it a houseplant that got too big?

Is it a wheelchair accessible tree-house?

None of the above. It is just weird architecture, designed to preserve a rare Chilean wine palm. The tree was probably planted in the front garden of a Victorian home that was on this site before the site was redeveloped. Chilean wine palms were more popular back then; and this one seems to be about that age. Although it seems to be healthy now, the constriction in the trunk indicates that it had been stressed by the redevelopment, which undoubtedly covered much of the established root system. The time it took for the length of trunk above the constriction to grow coincides with the estimated age of the building below. The tree very likely had better access to rainwater before.

Because it is a palm, the trunk…

View original post 156 more words

Tree Surgeons Evolved Into Arborists

Tree surgeons maintain the big trees.

Arborists are very specialized horticulturists. They prefer to work with trees. Of course that is not as simple as it sounds. Some are nurserymen who grow trees. Some select appropriate trees for landscape design. Even some of the orchardists who work with many trees of a similar type have earned this prestigious designation. Decades ago, we still knew many of them as tree surgeons.

Arboriculture, which is the specialized horticulture of trees, has certainly evolved through the decades. Tree surgeons no longer graft fruit trees directly in home gardens. Nurserymen graft trees in production nurseries, to make them available from retail nurseries. However, modern tree surgeons now work with much more diversity of many species that were unknown to their predecessors.

As storms become more frequent through autumn and winter, the need for arboriculture becomes more apparent. More unstable trees fall. More structural deficient limbs break. Many trees prefer to be pruned while dormant through winter. In actuality though, arboriculture is important throughout the year. Some procedures, for some sorts of trees, should happen significantly earlier or later.

Trees are the most substantial features of home gardens. Once they grow beyond reach, they need to be maintained by qualified tree surgeons. Regardless of what most say, very few gardeners are qualified to perform major arboricultural procedures. Many tree surgeons will attest to finding that most damage that trees endure is caused by gardeners with minimal regard for arboriculture.

Tree surgeons who are Certified Arborists of the International Society of Arboriculture, or ‘ISA’, have demonstrated their proficiency with arboriculture. After passing their certification examination, Certified Arborists maintain their credentials by continued involvement with educational seminars, classes and workshops of the ISA. Not many other horticultural professionals are so dedicated.

More information about procuring the services of an ISA certified arborist can be found at www.isa-arbor.com.

Hieroglyphs

P00606K
“111”? . . . “777”? . . . “TTT”? . . . “LLL”?

What does this mean? Is it ‘111’ deprived of the lower serifs? Is it ‘777’ with abbreviated arms? . . . ‘TTT’ lacking right arms? . . . ‘LLL’ with abbreviated legs? Is it pointing toward something important? Is a hieroglyph from an ancient language . . . or a language that has yet to be invented?! Is it like a miniature crop circle pattern cut into wood by Sasquatch or extraterrestrials?!

The arborist who left it here after cutting down the deceased ponderosa pine that formerly stood where this large stump remains might be amused to read that I contemplated it so intently. Actually, I did not really contemplate it so much. I only wrote about it as if I did because it is amusing to do so. I have no idea what this hieroglyph represents. I know that it is not important.

I have worked with enough respectable arborists to know that some of them prefer to leave their distinctive marks on the stumps of some of the impressively large trees that they cut down. In many of the suburban regions in which I work, most of such stumps get ground out shortly afterward. In the forested rural area here, such stumps remain until they rot and disintegrate.

On rare occasion, I encounter a familiar hieroglyph or the initials of a respected colleague. Now that we are as old as we are, familiar hieroglyphs are increasingly rare. Arboriculture is for the young. I sometime wonder about those who leave unfamiliar hieroglyphs. To me, the continuation of the tradition seems to indicate that they enjoy their work as much as my colleagues did.

That is important in horticultural industries. There are few in society who understand the appeal. We do what we do because it is what we enjoy.

Horticulture – It’s What I do.

P00506
Rhody, . . . because everyone loves Rhody, . . . and this is not about horticulture anyway.

This is not a misspelling of a misspelling. There is no misspelling of “Horticulture” in the title this week. “Horridculture” is typical of my rants on Wednesday. It is not the only deviation from the norm here. I included the contraction of “It’s” in the title. I have been trying to relax my otherwise objectionably uptight writing style; but a contraction in the title still makes me cringe.

Horridculture – It Is What I Do Not Do.” would be consistent with my style, but silly, and not so relevant to the subject matter. I am a horticulturist, arborist and garden columnist. I enjoy what I do very much, which is why I made a career of it. It is demanding work though, and does not afford much time for blogging. The quality of my blogging is consequently compromised.

I still work as many as three days weekly at a job that was supposed to be temporary two years ago! It is so excellent that I can not bear to leave, although I must eventually do so. It entails the maintenance of many acres of landscapes and forest at a Christian Conference Center. We have been unable to work for the past month, so will be busier than typical as we resume work.

Mondays and Tuesdays are my days for writing my weekly gardening column. I should probably retire from this work, but enjoy it so much, and would prefer to instead expand it into other publications to fill in the gaps between San Francisco and Los Angeles. I do intend to simplify this writing, even if expanding it; so that I can do it all on Mondays like I used to not so long ago.

For more than the past two years, I have not inspected trees or landscapes for other arborists or landscape professions. There just is not sufficient time! I do miss that work, and composing reports for those who dislike writing. (Arborists and landscape professionals who enjoy their trees and landscapes innately dislike writing.) If I ever resume such work, it will be only rarely.

I intend to eventually return to the farm where I belong, and resume production of horticultural commodities. As much as I enjoy the rest of what I do, growing things is what I do naturally. It is why my ‘temporary’ job was supposed to be ‘temporary’ two years ago. It will involve even more demanding work than what I already can not keep up with, but it is what I need to do.

Therefore, I will have even less time to devote to blogging. I intend to continue to post my brief weekly gardening column in two parts on Mondays and Tuesdays, as well as old articles from the same gardening column in two parts on Thursdays and Fridays. I would also like to continue with Six on Saturday and other brief posts for Saturdays at noon, Sundays and Wednesdays.

I write for my gardening column weekly regardless of the blog. Old articles from the column are already written. Only new posts for Saturdays, Sundays and Wednesdays need to be written separately; so some or all will be omitted if necessary. What I must discontinue now is my involvement with the many compelling blogs that I have been following for the past many months.

I will not stop following any of the blogs that I presently follow. I will just not be able to read all of the posts, or interact with them like I had been. For me, it will be quite a weird adjustment. I feel obligated to read much of what others post into blogs that I follow. If someone puts effort into positing it, then it must be important. I certainly enjoy how others interact with my blog.

I certainly do not want anyone to think that I lost interest in their respective blog. Many of them provide ideas for what I should write about within the context of my own weekly gardening column. Insight into horticulture in other climates, regions and even cultures has been fascinating. This is merely something that I must sacrifice in order to continue on with my own writing.

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?!?!

Pollarding Is Extreme Tree Pruning

50128thumb
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.

Horridculture – Tree Preservation Ordinances

P00108
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.

Six on Saturday: Tree Removal

 

The forest is constantly producing trees faster than we can cut them down. Even if we were not too busy with our many other tasks, we are not equipped to safely remove all of the large trees that become hazardous as they mature. Therefore, a crew who is so equipped is sometimes hired, and was here just this last week to remove several locusts, a few bays and a live oak.

1. The 80s are over. Someone painted this water pipe like this so that a crew cutting trees down nearby would not drop anything on it. The crew would have just put an orange cone over it.P91109

2. I was much younger and healthier back in the summer of 1988, when I did an internship with some of the most excellent arborists in the Santa Clara Valley, but I never climbed like this.P91109+

3. These trees are not much more than eighty feet tall, but needed to be parted out over those roofs. They are less than forty years old, from the 1980s or so. The arborist is in the middle.P91109++

4. Locust is unpopular firewood. These locust trees were therefore cut into logs less than seven feet (or 84 inches) long to fit into a pickup for removal, but were then instead chipped on site.P91109+++

5. This structurally deficient oak will eventually need to be removed. For now, it is groomed and lightened for winter storms. It was a nice day at the time, with temperatures in the low 80s.P91109++++

6. Mature bay trees develop distended lignotubers. The trunk of this bay tree was significantly narrower just two feet above this stump. The tree was not much more than eighty years old.P91109+++++

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

https://thepropagatorblog.wordpress.com/2017/09/18/six-on-saturday-a-participant-guide/