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.

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

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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.

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.

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+

Street-Smart Gingko

P91124Much of my work involves street trees. They need more of my kind of attention than most other trees. They must conform to more restrictive limitations. They endure more abuse. They are the most prominent trees on urban properties. Because some are assets of their respective municipalities, they are more stringently protected by local ordinances than other trees are.

I planted quite a few street trees too. While selecting trees for the medians of San Vicente Boulevard in Los Angeles, we considered the clearance of the lowest limbs above the highest truck traffic, the docility of roots under curbs and pavement, the potential for foliar debris, the resiliency to neglect, and the resistance to pathogens. Those were just some of the major concerns.

We sort of wanted them to look good too.

Ginkgoes, at least modern (fruitless) cultivars, work well as street trees. They are tall and slender, and can be pruned for clearance above streets and sidewalks. Their roots are reasonably complaisant, and take many years to displace concrete. ginkgoes defoliate neatly in autumn, with no debris for the rest of the year. They are resistant to pathogens and tolerant of neglect.

They also look great in their monochromatic but brilliant yellow fall color. (Try to not notice all those utility cables.)

This pair of ginkgoes is in front of an old home in town that was formerly the office of the Los Gatos Weekly Times, before it expanded into the larger Silicon Valley Community Newspapers group. Two decades and one year ago, this was where I dropped off the first of my weekly gardening columns, first as hard copy on paper, then on floppy discs. The trees were smaller then.

One day back in about 1999 or so, I stopped by on my way back from delivering rhododendrons and other horticultural commodities from the farm. I was driving the big delivery box truck. I realized how important adequate clearance is when the truck tore a significant limb from the tree on the left. The tree and I both can attest to the resiliency of the species to such abuse.P91124+

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/

Horridculture – Sealant

P90810++++Grafting compound is a thick sealant applied to a fresh graft union to limit desiccation while the graft knits. A bit more typically gets applied to the cut distal end of the scion. There are various formulations of grafting compound, ranging from something resembling roof patch to a something with the consistency of thick paint.

The stuff, as sloppy and icky as it is, really is helpful. I can not imagine how big orchards were grafted before it was invented.

It is also useful for keeping cane borers out of the cut ends of freshly pruned roses. For those of us who remember how to prune roses properly, leaving only a few thick canes, grafting compound really is practical. I just don’t use it on roses because cane borers are not a problem here.

Since I do not use grafting compound on roses, and the plants that I graft do not need grafting compound, I presently have no use for it. I suppose I could use it on apple and pear trees, but it really is not necessary. When I get around to grafting apricots and peaches, it will only be for a few trees in my own garden, so I will just use candle wax.

This surprises people. At work, I am often asked about ‘painting’ pruning wounds and shiners as trees get pruned, presumably with sealant. Decades ago, it was actually commonly done. Even when I did my internship in arboriculture in 1988, some arborists were applying sealant because it was easier than arguing with their clients about it not being necessary.

The problem with applying sealant to large wounds is that is actually seals moisture within the otherwise exposed wood, and promotes rot. It is best to do nothing, and allow the affected trees to compartmentalize their wounds as they would do naturally if limbs were broken off by the weather. Trees know more about their processes than we do.

X Marks The Spot

P91102KHorticulture is not all about growing things. If everyone was out planting trees, the World would eventually be overwhelmed with forest. It is sometimes necessary to cut trees down. There are several at work that we have been wanting to cut down for quite a while. Some are structurally deficient enough to eventually become hazardous, which is unacceptable in public spaces.

Even here among some of the oldest trees in the World, nothing last forever. Coast live oak, like that in the picture above, has potential to survive for centuries, but eventually succumbs to decay and disease. If fact, this particular specimen is doing it right now. If not cut down soon, it will eventually fall onto an adjacent building and a parking lot below. Its days are numbered.

Literally, it will be cut down on Monday morning, along with a few other coast live oaks and bay laurels in the neighborhood. The orange ‘X’ on the trunk is so faded from the delay of getting this done, that is it barely discernible. (Actually, the can of spray paint was empty.) The trunk and even the main limbs are so rotten that there will not be much firewood left to cut and split.

Cutting this tree down may seem to be unnatural, but so was pruning it for decades so that it would not fall down. It is impossible to say what situation this tree would be in now without past or present intervention. I am more concerned with how it and other trees interact with their surroundings, and the safety of everyone involved. We can not always let nature do as it pleases.

Forest fires are very natural components to our local ecosystems, but because so many of us live here, significant effort and resources are expended on containment!

Arborists Maintain The Big Trees

91106thumbThe trees know what time of year it is. Even evergreen trees have shed some of their older foliage through late summer. Deciduous trees generally start later, but will be more blatant about their process as they defoliate completely through autumn to winter. Some get strikingly colorful first, as if to brag about it. Foliage is not so important during shorter days and dimmed sunlight anyway.

By the time storms start to arrive later in autumn, trees intend to be ready. There will be less foliage to be blown by wind, or to absorb the weight of the rain. Remaining deciduous foliage is likely to be dislodged by wind and rain before supporting limbs succumb. Trees will be mostly dormant, so will not mind so much if a few minor limbs do happen to get broken. They know their routine.

For many types of trees, this is a the best season for major pruning. While dormant, they are much less likely to be offended by it. In fact, they sort of expect to wake up in spring with a few limbs missing. They do not distinguish what was pruned away from what might have been broken by the weather. Besides, it is better to prune questionable limbs civilly, before they get broken brutally.

Trees that are beyond reach will need the attention of professional arborists.

Arboriculture is merely the horticulture of trees. An arborist is therefore a horticulturist who specializes in trees. They assess the health, stability and structural integrity of trees, and prescribe any necessary arboricultural procedures. They or their associated crews are qualified to perform the work that the trees need. The most proficient of arborists are those who are certified with the ISA.

The ISA is the International Society of Arboriculture. ISA Certified Arborists have passed an examination of their arboricultural expertise, and maintain their credentials by continued involvement with ISA educational seminars, classes and workshops. Information about the International Society of Arboriculture and local certified arborists can be found at their website, www.isa-arbor.com.