Posted on by tonytomeo · 4 Comments

Six on Saturday: Do Not Sit On Tree

 

1. Seriously!P90810

2. Allow me to explain. This is one of three small but very gnarly coast live oaks that grew from the roots of a single tree that was cut down or fell several decades ago. Because the trunks of the three trees are so horizontal and sculptural, children climb on them. Sometimes many children sit on the trunk of this particular tree to get their group picture taken. We had been concerned about how this might compromise the stability of the tree for quite a while. Before we constructed suspension devices to prop it and one of the other two trees with, it destabilized and sagged! We pruned much of the canopy away to eliminate some of the weight that exerts so much leverage against the root system, and propped the trunk with a saw horse. We hope that the tree survives the loss of roots that likely broke away in the process, but would not be surprised if it does not. We are not ready to cut it down. It and the two other trees are so well known and popular among guests. The sign is visible to the right. I will explain the colored yarn on the trunk in a moment.P90810+

3. The subject tree is to the lower right in this picture. The two other trees are sprawled to the upper left. The tree that extends farthest to the left will get propped as well. All three have been pruned more aggressively than they should have been to eliminate much of the weight.P90810++

4. The yarn on the trunks is decoration that the camp counselors installed prior to the arrival of the guests. It must have taken a long time to wrap this much yarn around the trunks, and there is a whole lot more in many other trees. I wrote about it earlier in ‘Boom! Zap! Wow! Bam! Zing!‘.P90810+++

5. This is a completely different coast live oak, with a completely different problem. It needed to be pruned for clearance from an adjacent roadway and walkway. The major limb that was here supported less than one tenth of the total canopy, but because it had been cut back repeatedly, it was unusually bulky. Consequently, the shiner that remains is about as wide ad the remaining trunk! That is VERY arboriculturally incorrect. To make matters worse, the cut was not at the correct angle, so eliminated the lower half of the ‘collar’ that is supposed to expand to compartmentalize (heal) the shiner. The problem now is that by the time the shiner heals, the interior of the trunk may be so rotten that the tree may need to be removed anyway. The limb needed to be removed. The only other option was to remove the entire tree.P90810++++

6. Nothing was done to this coast live oak. It grew like this naturally. Although not an exemplary specimen, it certainly is impressive.P90810+++++

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/

Posted on by tonytomeo · 5 Comments

Suckers For Street Trees

P90804This grand sycamore has likely been here since the third day of Genesis. A few of the top branches got broken off when Noah’s Ark floated over. When I was a little kid, it was on the edge of a vacant field where road debris was dumped, and older kids rode their dirt bikes. Now it is on the western edge of the parking lot of Felton Covered Bridge Park. I write about it sometimes.

‘California Sycamore‘, ‘Hanging Gardens Of Babylon‘, ‘Nature Is Messy‘ and ‘Tufts‘ are some of the articles that feature this exquisite specimen. The last three of these examples describe some of the difficulties of old age for sycamores. Something that I may not have mentioned in these article though, is that such mature sycamores eventually develop root suckers.

I use the term ‘suckers’ loosely. For those of us who grow grafted trees, ‘suckers’ are stems that develop from below the graft unions of grafted trees, even if above the roots. They are from the understock below, so are genetically different from the scions above. Unusually vigorous stems above graft unions or on ungrafted trees, including the roots, are known as ‘watersprouts’.

For all other intents and purposes, ‘suckers’ really are just vigorous stems that emerge from roots, which is what we have here. Because no one was here to graft this grand sycamore on the third day of Genesis, these ‘suckers’ are genetically identical to the main tree. Unfortunately, their appearance indicates that the tree is finally acknowledging that it is slowly deteriorating.

Many trees do it, especially old riparian trees. When they know that they will not be around much longer, but still have some time to do so, they divert resources into their own replacement. Suckers are expected to mature into new trees after the original is gone. They recycle the mature original root system until they eventually replace it with younger and more vigorous roots.

Arborists may try to interfere with this process by removing suckers and watersprouts, and diverting resources back into older stems. This is actually helpful for trees that are distressed, but not yet decaying. For trees as mature as this sycamore, removal of vigorous suckers and watersprouts is mostly cosmetic, because thickets of such rampant growth becomes unsightly.

As violent as it sounds, it is best to abscise suckers like these when they first appear, and any that appear afterward. That involves literally tearing them from their roots to remove some of the callus growth from which they emerged. Cutting them at the ground not only leaves the callus growth to develop into distended burls, but also stimulates more vigorous sucker growth!

Now that these suckers have been cut down repeatedly over the past several years, simple abscision is no longer possible. Callus grown has expanded and fused into broad subterranean burl growth. Removal of such extensive burl would severely distress and possibly contribute to the destabilization of the already distressed tree. Suckers can now only be cut down to the ground.

Several years ago, when the first of the suckers started to appear, they were much easier to abscise. The process was delayed until winter dormancy. The small defoliated suckers were then abscised along with much of their associated callus. It did not accomplish much for the massive tree, and only delayed the inevitable for a few years, but generated an interesting byproduct.

The bare suckers with their bit of callus were ideal for growing into copies of the same tree. Most were plugged back into the riparian area nearby, but later killed by necessary vegetation management. A few others were canned (potted), and grew into small sycamore trees that were planted, with other sycamores, into broad medians and parkstrips in Mid City Los Angeles.

It is a long story about how those few trees ended up in Los Angeles, and were added to the fifty or so Birthday Trees that we plant annually on January 18. Sadly, their identities were lost in the process. If the other sycamores are genetically identical clones of each other, it may eventually be possible to distinguish genetic variations of those that were once root suckers here.

Posted on by tonytomeo · 15 Comments

Horridculture – Microtrees

P90731We arborists happen to like trees. That is why we are arborists. Most of us also understand that trees are not appropriate for every situation, or where they are not appreciated. There is no point in planting a tree where it will just get cut down by someone else who does not like it. We want trees to be happy. We also want those who live with them to be happy with their trees.
Trees are ‘generally’ desirable over parking lots and roadways. They provide shade that cools the pavement during hot summer weather. Arborists naturally prefer trees that get big enough to make substantial shadows. It is also important for such trees to get high enough to be pruned for minimal clearance above the biggest vehicles to use the roadways or paring lots. They should also be pruned above streetlamps and signs.
Clearance of signs is a serious problem in strip malls and commercial districts, where trees are regularly disfigured by those wanting to keep them below their signs rather than above. It takes a few years to prune trees upward, and many merchants do not want to wait that long. There is also a concern that substantial trees will make substantial messes, and damage concrete curbs, gutters and sidewalks.
Microtrees are not always the answer! They are a cop out! For many situations, it is better to contend with the problems of larger trees than to pretend that microtrees are somehow better.
These dinky crape myrtles will never be proportionate to the roadway to the left or the parking lot to the right. They will not get high enough to be pruned for adequate clearance, so will instead be mutilated for confinement. They will likely get shorn into nondescript globs that rarely get a chance to bloom, and that pedestrians will need to duck under.
Crape myrtle is the most common of the microtrees that so commonly end up where other trees would be better. That is why so many arborists sometimes misspell ‘crape myrtle’ without the first ‘e’.

Posted on by tonytomeo · 7 Comments

Horridculture – Street Tree Neglect

P90717Many municipalities enforce tree preservation ordinances. Whether we agree with them or not, these ordinances are designed to preserve significant trees that are assets to the community. For the greater good, local governments have made it their business to limit what we can do with our own trees on our own properties. There are many advantages. There are many disadvantages. We arborists see it all.
Street trees, by general definition, are those that are close enough to a curb to shade a roadway and parked cars. In suburban and urban neighborhoods, many street trees are within parkstrips, which are the narrow spaces between curbs and sidewalks.
Neighborhoods of tract homes are typically outfitted with uniform trees of only one or two cultivars, that were all installed at the same time, as the homes were completed. Some neighborhoods of homes that were built individually are also outfitted with conforming street trees that were installed as parcels were subdivided. Most of such trees were installed as contingencies to development of the sites.
Since such trees were required by the associated municipality, they used to be maintained as such, just like any other trees in parks, medians or other public spaces. Municipalities that lacked tree preservation ordinances protected street trees as the public property that they were considered to be. Those who owned homes that were outfitted with such trees were not allowed to cut them down or even prune them without permission.
In some ways that sounds like a pretty good deal. The problem was that for many municipalities, it did not last. As the maintenance of maturing trees continually became more expensive, resources that used to be allocated for the maintenance of street trees were diverted to other projects. Although they do not like to talk about it, many municipalities no longer maintain their street trees, or do so selectively.
The aging trees remain. Many get cut down secretly by property owners who get frustrated by the lack of maintenance. Most are well maintained, but at the expense of those who own the properties where such trees live.
Most of us probably do not mind paying to have our street trees pruned when necessary. However, it is frustrating for those of us who must contend with some of the more problematic trees, and trees that are unusually expensive to maintain. Furthermore, property owners must assume the expense of repairing sidewalks, curbs and driveways that are damaged by roots, as well as damage to anything that limbs fall onto.
Municipalities that once required the installation of street trees, and that should still be encouraging residents to protect and appreciate their urban forests, are no longer able to assume the liability associated with street trees.
These pictures show two large limbs that fell from a big Canary Island pine onto two parked cars in Leimert Park of Los Angeles. A concerned citizen had contacted the Los Angeles Department of Public Works a few times about the tree, because one of the two fallen limbs had broken off quite some time ago, and was entangled with the other limb that broke and fell shortly before these pictures were taken on Sunday morning.P90717+

Posted on by tonytomeo · 4 Comments

Arborists Are Modern Tree Surgeons

90724thumbThe terminology has certainly changed over the years. Not many of us remember what tree surgeons were, or that there were actually a few different kinds of tree surgeons, who performed very distinct tasks. Tree surgeons are now known as ‘arborists’. Much of what they used to do is done by other types of horticultural professionals. The work that arborists still perform is ‘arboriculture’.

Back when orchards were still common in the Santa Clara Valley, Orange County, and many of the areas of California that are now urban, those who pruned deciduous fruit trees while dormant in winter were known as tree surgeons. Of course, they did other work that the trees needed through the rest of the year, and harvested fruit as well. They might be known as orchardists nowadays.

Tree surgeons also assembled new orchards, as well as individual trees in home gardens. It used to be standard procedure to install the understock of fruit trees in the first winter, and let it grow through the following year. A tree surgeon would return while it was dormant the following winter, to graft desired scions onto it. This is now done by nurserymen in nurseries that sell finished trees.

The tree surgeons who we now know as arborists are, of course, still important. The tree surgery that we now know as arboriculture is the sort or work that other horticultural professionals are not qualified or able to perform. It involves the biggest of trees that are out of reach from the ground, or even from ladders. There are still a few different kinds of arborists, but most must climb trees.

Arboriculture is the horticulture of trees. Arborists are therefore horticulturists of trees. Those who are certified with the International Society of Arboriculture, or ISA, have passed an examination of their arboricultural expertise, and maintain their credential by continued involvement with the educational seminars, classes and workshops of the ISA. Arborist can assess the health, stability and structural integrity of trees, and prescribe and supervise necessary corrective arboricultural procedures.

Posted on by tonytomeo · 11 Comments

Horridculture – Tree Removal Permits

P90703There are mixed emotions about tree removal permits that so many municipalities need to issue in order for a ‘heritage’ tree to be cut down legally. Most of us want to believe that in America, we have certain rights to do what we want to on the properties that we own. Obviously, that makes the most sense. However, if it were that simple, many more prominent trees that are collective assets to the larger communities would be removed.
As an arborist who writes the reports needed to procure these permits, I see it both ways. There are many trees that are worth preserving for the Community, and there are probably many more that must be removed for the safety of those who live around them.
I sometimes hear of common homeowners who get fined for removing a tree without a permit, just because they were not aware that it was protected by an ordnance. Most have lived in their homes longer than such ordinances existed. Most planted the tree that they were fined for removing.
Conversely, I also hear about developers who just remove whatever trees get in the way of their developments, and then just pay the necessary fines. It is nothing to them because they make so much money from the development.
The picture above is a site that one of my former employers worked on just before I left my job because it was too morally challenging. You can see that there are no significant trees. The tree crew removed all of them.
I was not aware of it of course. The Home Owners Association did not want to pay for my inspections and reports, or for the permits to remove all the big sycamores in the front gardens there. Nor did they want to replace the removed trees with something more proportionate, as the local municipality would have required. They were not worried about getting caught, since everyone there wanted the trees gone.
Now realistically, I would have had no problem writing reports recommending the removal of all the trees, because they were ridiculously disproportionate to their particular application. You can see how tiny the front gardens are. It was just easier and less expensive to cut the trees down illegally, and then not be required to replace them with trees that would have later died ‘accidentally’ anyway. (The tree crew excelled at that too.)
In the end, it is disgraceful that the trees that were required as a contingency when the site was developed years earlier are now completely gone, and will not be replaced, . . . and that no one seems to care.

Posted on by tonytomeo · 5 Comments

Horridculture – Metasequoia glyptostroboides

P90626The easier name is ‘dawn redwood’. I just used the big and fancy Latin name because that is how landscape designers with something to prove say it. If the big name does not impress clients, an explanation of how rare it is, and that it is one of only a few deciduous conifers, will likely do the job. Even back when it was still a fad, I got the impression that was its main function; to impress clients.
It is not even a particularly practical tree. If it gets too big for its situation, it is difficult to contain without disfiguring the canopy. Because the priorities for most were conformity to a fad and to dazzle a client, not much thought went into their appropriateness to their respective landscapes. Consequently, many went into landscapes that were not big enough for them.
Although deciduous, dawn redwood does not even get good color in autumn. It just turns rusty brown, and quite frankly, looks dead.
It is true that there are only a few deciduous conifers. However, the dawn redwood stopped being rare shortly after it became a fad. I mean, how rare can it be if every landscape designer with something to prove gets to plant one?! Isn’t that what happened to the formerly rare yellow clivia after it became a fad?
The only one that I work with now happened to be planted before dawn redwood became a fad. I suppose that makes it okay. It is quite tall now, and has plenty of space to mature. However, I can not help but notice how silly it looks with all the other surrounding coastal redwoods. Although very different, it is similar enough to look like a coastal redwood with some serious problems, especially when it seems to die every autumn.

Posted on by tonytomeo · 14 Comments

Spontaneous Limb Failure Is Real

90605thumbIt sounds like science fiction, but it is not. Every spring and during particular summer weather, limbs can fall from trees without warning, and seemingly for no reason at all. It happens when least expected, while the weather is warm and perhaps humid, but notably without wind. The lack of wind is what makes it so unexpected. It is a phenomenon known simply as spontaneous limb failure.

Those who witness it might think that the arborists they call to clean up the mess will not believe their descriptions of what happened. Yet, arborists are familiar with it. Quite a few species of trees are notorious for it, especially in urban landscapes where they get watered regularly. Most of such trees are either chaparral trees that do not expect much water, or riparian trees that do expect it.

Spontaneous limb failure occurs as warmth accelerates vascular activity, but humidity inhibits evapotranspiration, which is evaporation from the foliage. Accelerated vascular activity increases the weight of the foliage. Inhibition of evapotranspiration limits the ability of the foliage to eliminate some of the excess weight. Limbs break if unable to support the increasing weight of the foliage.

Spontaneous limb failure is not as easy to predict as the more familiar sort of limb failure that is caused by wind. Limbs that get blown down typically exhibit some sort of structural deficiency or disfigurement prior to failure. Some limbs that succumb to spontaneous limb failure do so as well, but most do not. They just happen to be the healthiest and most densely foliated parts of a tree.

Native coast live oak and valley oak are the two most familiar of the chaparral trees that are notorious for spontaneous limb failure. Native cottonwood, willow, box elder and sycamore are riparian trees that are perhaps even more susceptible to spontaneous limb failure. Sweetgum, carob, stone pine and various eucalypti are some of the exotic trees that might drop limbs spontaneously.

In summer, spontaneous limb failure is less likely as growth slows and limbs strengthen.

Posted on by tonytomeo · 6 Comments

Campground II

P90626This is a formerly unplanned sequel to the article ‘Campground‘ from last Sunday. That article described my concern for any of the homeless who might camp on the banks of an adjacent creek, below innately unstable and structurally deficient riparian trees. Just a few minutes after the article posted at midnight, the biggest and most deteriorated box elder tree in the area of concern coincidentally fell! No one was there at the time to be hurt.
The tree that fell was located just a few yards to the right of those in the picture of the previous article. It happened to be the only tree that was inside the fence. Therefore, as it fell inward, it did not damage the fence. The trailer that it landed on is for heavy tractors, so was undamaged. Only the top few timbers of a pile of lumber that it landed on were broken, and only because the lumber was recently milled, and stacked so loosely to dry.
The upper picture at the top shows the fallen tree laying on the trailer and loosely stacked lumber, with its dislodged trunk suspended above the ground. The middle picture here shows the base of the dislodged trunk suspended pitiably above the ground, with no roots remaining attached to the soil.P90626+

The lower picture below shows how efficiently the trunk pulled out of the crater as if there were no roots holding it down. The few roots that were there were so decayed that none stayed attached to the soil. It is amazing that the tree did not fall earlier! When if fell, it sounded just like one might imagine it would, with a loud but quick crash. There was no sound of tearing or crunching roots. Fortunately, there was no one else there to hear it!P90626++

Posted on by tonytomeo · 8 Comments

Campground

P90519There happen to be quite a few campgrounds in the region, with one about a quarter of a mile upstream from where this picture was taken, and another less than three miles past that. Both are primarily used by school age children. The vast redwood forests with creeks flowing through are ideal for such campgrounds.
This is a campground too. I know it does not look like it. It is located between a creek and an industrial building, the eave of which is visible in the top right corner of the picture. The herd of dumpsters that is barely visible at the bottom of the picture might include a dozen dumpsters at at time. (I tried to get both the eave and the dumpsters in one picture.) There really are two rows of barbed wire on top of that fence behind the dumpsters.
Nonetheless, it is a campground. You see, individuals who lack adequate shelter occasionally camp on a flat spot next to the creek, right below the big cottonwood tree in the middle of the picture. It is not a big space, so can only accommodate one or maybe two people at a time. No one has been there for quite a while. Yet, on rainy days like today, it is saddening to imagine someone camping there, so close to inaccessible buildings.
Because the area is outside of landscaped areas, I do nothing to make it any more comfortable as a campground. I only cut away the limbs that fall onto the fence.
The trees are a mix of mostly box elders, with a few cottonwoods and willows, and even fewer alders, with one deteriorating old bigleaf maple. They concern me. Box elders, cottonwoods and willows are innately unstable. All but bigleaf maple are innately structurally deficient. Although bigleaf maple should innately be both stable and structurally sound, the particular specimen in this situation is in the process of rotting and collapsing.
I really do not mind if limbs or entire trees fall into the forested riparian zone. If they fall outward, they do not damage the dumpsters. Only the fence needs to be repaired. What worries me are the potential residents of the campground. Part of my work is to inspect trees for health, stability and structural integrity, and if necessary, prescribe arboricultural procedures to make them safe. I just can not do that here.

UPDATE: Just after this article posted at midnight, a very big box elder off to the right of those in the picture fell with a loud but quick crash. It was probably the biggest and most deteriorated of the box elders in this area, and pulled completely out of the ground to reveal that the roots were so decayed, that none stayed attached to the stump. Seriously, you should see the pictures when they get posted next Sunday.