California Sycamore

41119Out in rural chaparral regions, where water is scarce, the big and bold California sycamore, Platanus racemosa, somehow seems to find the spots where groundwater is not too far below the surface of the soil. It is technically a riparian tree, that is just as comfortable competing with cottonwoods and willows along forested rivers and floodplains. It eventually get too big and messy for refined urban gardens, but is somewhat popular nonetheless.

The bulky trunks and limbs are just too striking to ignore, especially as trees defoliate to expose the mottled beige and gray bark. Trunks are typically leaning and irregularly sculptural. Many trees have multiple trunks. The biggest trees are a hundred feet tall. The big palmately lobed leaves can be eight inches wide, but unfortunately do not color well in autumn. The foliar tomentum (fuzz) can be irritating to the skin when leaves need to be raked. Athracnose causes much of the early spring foliage to fall, and sometimes distorts and discolors later summer foliage.

Arborists Specialize In Tree Horticulture

0

Why is it so difficult to believe that there are so many different kinds of horticultural professionals? No one is ever surprised that surgeons, cardiologists, dermatologists, ophthalmologists and pulmonologists are all physicians. Yet, those who do not know better consider all horticultural professionals to be ‘gardeners’. This is actually more insulting to real professionals than outsiders can imagine, because the gardening industry is more dominated by non-professionals than any other horticultural industry.

Nurserymen, landscapers and florists are also horticultural professionals. Each of these basic categories can be divided into more specialized professions. For example, production nurserymen grow nursery stock or other horticultural commodities, while retail nurserymen maintain plant material only long enough to sell it. Maintenance gardeners are probably the most familiar of horticultural professionals because so many of us use their services around our home gardens.

Arborists are the horticulturists who specialize in trees, and really should be more familiar than they are. The only landscapes that have no possible use for their services are those that are devoid of trees. Even the most proficient of maintenance gardeners should not be expected to maintain large trees or diagnose potential arboricultural problems, not only because arboriculture is so specialized, but also because maintenance gardeners have their own specialties to be concerned with.

Because trees are the most substantial features of a landscape, and they have the potential to cause proportionate problems if not maintained properly, it is very important to have them maintained by qualified arborists. Those who are certified by the International Society of Arboriculture, or ISA, have passed an exam of their expertise, and maintain their certification with regular involvement with the ISA. Such involvement includes attendance to arboricultural seminars and classes.

It is ironic that some of the least familiar of horticultural professionals need to stay so dedicated to the maintenance of their credentials. Certified arborists can be found at the website of the ISA at isa-arbor.com.

Horridculture – “One Of These Things . . . “

P91120Remember this from Sesame Street?

One of these things is not like the others
One of these things just doesn’t belong
Can you tell which thing is not like the others
By the time I finish my song?

Identifying a blue balloon as different from three red balloons might be construed as discriminatory, but was fun back before we went into kindergarten. So was selecting the bigger bowl of Big Bird’s birdseed from three small bowls; or the beanie from three pairs of sunglasses; or the letter from three numbers. It is not so fun now, when conformity to a landscape is important.

In the picture above, one of the four prominent trees in the foreground of the walkway and rail fence, excluding the obscured middle tree, is different from the others. They are all the same age. They are all sycamores. They are all happy and healthy. They were all supposed to conform to the landscape of native vegetation in the background. Which thing is not like the others?

The second tree from the left is a London plane, Platanus X acerifolia. The other trees, as well as the fifth middle tree and the sycamores in the background, are native California sycamores, Platanus racemosa. Not only is the London plane not native, but it is distinctly smaller and more symmetrical, with a conspicuously straighter trunk and relatively orangish autumn foliage.

The picture below shows the bark of London plane, with a trunk of a California sycamore in the background. The second picture shows how dissimilar the bark of the California sycamore is.P91120+P91120++

Individually, there is nothing wrong with the London plane. A few could have made a nice homogenous grove in the same spot, although they would never attain the grand scale expected of California sycamore. The problem is that the London plane is similar to, but not the same as, the California sycamores. It will always look like one of the California sycamores with problems.

A completely distinct tree would have been better. If it were a redwood or a magnolia, or anything that is not so similar to California sycamore, it would not be expected to conform to them.

I see it commonly. Himalayan birch get added to groves of European white birch, even though their trunks are whiter and straighter, and their canopies are much more upright. Taller and leaner Mexican fan palms get added to otherwise formal rows of California fan palms. The formality of rows of tall and slim Lombardy poplars is similarly disrupted by fatter Theves poplar.

These bad matches are often honest mistakes. It is not easy to distinguish Theves poplar from Lombardy poplar; and Lombardy poplar is rarely available. Sometimes, so-called ‘gardeners’ or ‘landscapers’ simply do not care. An ‘Aptos Blue’ redwood was added to a grove that was exclusive to ‘Soquel’ in a nearby park, just because it was closest to the parking lot at the nursery.

So-called ‘landscapers’ sometimes ‘sub’, or substitute, a commonly available cultivar or species for something that was specified by a landscape design, but is not so readily available. It often works out just fine. However, I once inspected a landscape in which a ground cover cultivar of cotoneaster was subbed with Cotoneaster lacteus, which promptly grew higher than the eaves!

European White Birch

91127Like a flower girl scatters rose petals ahead of a wedding procession, European white birch, Betula pendula, tosses its small deltoid leaves soon after turning soft yellow with autumn chill. Color may not last long on the trees, but becomes a delightful mess for those who appreciate such assets. The primary allure though, is the slender strikingly white trunks, accented with black furrowing.

European white birch is very informal, but also elegant enough for formal landscapes. To best display their gently leaning white trunks, they are popularly planted in relaxed groups. Their canopies are neither broad nor dense, so a few fit together nicely. As lower branches get pruned away, pendulous upper branches sway softly in the breeze. Mature trees are mostly less than fifty feet tall.

Himalayan birch, Betula utilis or Betula jacquemontii, which has become more popular than European white birch since the 1990s, has a completely different personality. Its strictly vertical trunks and upright growth are appealing separately, but incompatible with European white birch. When adding trees to an established grove of any birch, it is very important to procure more of the same.

Autumn Weather Prompts Foliar Color

91127thumb(alternate)Mild climates allow more flowers to bloom through autumn and winter here than in most other parts of America. That is why cool season annuals like pansies and violas are so popular. Cyclamen can be planted now too. None will be obscured by snow. By the time cool season annuals start to fade, warm season annuals will be replacing them. There is something to bloom in every season.

There are a few disadvantages to mild climates, though. Many plants rely on significant winter chill to stay on schedule. Inadequate chill limits the cultivars of apples and pears that are productive here. Not many spring bulbs will naturalize. Prior to winter, some deciduous plants are hesitant to resign to dormancy until they experience a chill that is cool enough to convince them it is autumn.

Some deciduous plants recognize a specific temperature as credible evidence of a change of seasons. Others want a specific temperature to be sustained for a specific duration or repeated for a few nights. Shorter days and longer nights are taken into consideration by species who want to confirm what they deduce from the weather. Different plants use different methods of observation.

That is why deciduous plants who develop foliar color before defoliating in autumn do so on their own terms. Weather conditions that promote excellent color among birches may not be the same that cause flowering cherries to color well. Warmth and minimal humidity that sometimes prompt premature and blandly colored defoliation of sycamores might enhance later color of sweetgums.

Sweetgum, Chinese pistache, flowering pear and ginkgo are the most reliable trees for foliar color in autumn. Ginkgo turns only brilliant yellow. The others exhibit an excellent mix of yellow, orange and red. Crape myrtle can be about as colorful, but is not always as reliable.

Of course, there is more to these and other deciduous trees than their colorful foliage in autumn. After all, they are trees. Their particular characteristics and appropriateness must be considered before adding any of them to a landscape.91127thumb

Rose Hips

P91117Chopped dried rose hips can be purchased from a supermarket in town that stocks an impressive variety of useful bulk herbs. They are used as a dietary supplement and remedy for several minor ailments. Although most of the copious vitamin C they contain while fresh is ruined by drying and storage, they are still popularly used as a remedy or preventative for colds and flu.

It would be reasonable to assume that the rose hips that are available in markets would be from a species that has been cultivated and developed for a few centuries. After all, rose hips have been used as an herbal supplement for a very long time. Surprisingly, those that are available in the local market here are from the common and native California wild rose, Rosa californica.

That means that those that grow wild on the outskirts of the landscapes here produce the same rose hips that can be purchased in markets. There are only a few others species of wild rose that grow wild in California, and even fewer that are endemic locally. Those in the picture were actually planted into a landscape composed of natives, but are thought to be Rosa californica.

I normally leave these rose hips for the birds; but because the birds take all my cotoneaster berries, I am not too worried bout them getting enough to eat. I left the rose hips that are pretty where they can be seen, but took quite a few that were out of view on the backside of a riparian thicket of rose bramble. I do not yet know what to do with them, but will figure that out later.

Once dried, these rose hips will be easily pulverized into coarse and seedy ‘grounds’ that can be added to blends of herbal tea.P91117+

Not Quite Rain

P91116KMost of us here agree that the minimal bit of precipitation that fell from the sky on Thursday was not real rain. There are a few different theories about what it actually was though. It could be considered to have been drizzle. It alternatively could have been heavy fog or mist. Some of us make up silly names for what it was, such as fine rain, dusting, spritzes, sprinkles or mizzle.

Is it just me, or do those last three sound like inane kitten names? ‘Dusting’, sounds dirty and dry, which it was not.

Whatever it was, it was the second occurrence of such precipitation since the rainy season ended last spring. Something similar happened on the last day of September. I wrote about it in my other blog, with a picture of it on the hood of a parked car, rather than the windshield. I think it was more of a surprise then because it was earlier, and the chance of precipitation was slim.

This weather pattern is still within what would be considered normal here. The rainy season typically starts a bit earlier, even if with just a single primary storm passing through, followed by a long pause before more follow. There is no strict schedule though. We know that the rain will eventually start, and that rainy seasons that start late tend to provide significantly more rain.

Rain is likely just as uncomfortable here as it is everywhere else. Perhaps it is even dirtier, because it rinses off dust and crud that has been accumulating since spring. No one wants to work in their garden while it is wet. Nonetheless, because there is no rain for nearly half the year, the first storm of a season is something to be celebrated. The forecast predicts no celebration yet.

Six on Saturday: The Endless Summer

 

Summer really did end here. There was a minimal frostless frost to prove it more than two weeks ago. This climate just happens to lack the more apparent seasonal changes that others get to show off. Except for a bit of drizzle last Thursday, and a bit at the end of September, there has been no rain since last spring. It may seem to be boring, but such weather is normal here.

1. There is typically more foliar color by now. Sweetgums are only beginning to yellow. However, these dogwoods started to defoliate early without much color. This is about as good as it got.P91116

2. Not all of the warm season annuals have been replaced with cool season annuals. These petunias are blooming too happily to be replaced with pansies or violas like we installed elsewhere.P91116+

3. Roses continue to bloom. This one looks like ‘Double Delight’ to me. I really do not know what it is. The flowers are rather small, so it must have noticed that nights are longer and cooler.P91116++

4. These two look silly to me because both are grafted together onto the same standard (tree rose). I believe they are ‘Iceberg’ and ‘Burgundy Iceberg’. I would not mind them individually.P91116+++

5. Even by our local standards, roses should be finishing by now, with only a few that are still blooming when they get pruned in winter. I do not know what this one is, but it still looks great.P91116++++

6. This is my favorite of these six pictures. I do not know what this rose is either. It is in a neighbor’s garden. It did not start to bloom until part was through summer, and is now at its best.P91116+++++

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/

Kalanchoe

41112It is unfortunate that, like Easter lilies and poinsettias, most kalanches, Kalanchoe blossfeldiana, are enjoyed while actively blooming, and then discarded as their blooms fade. It is so easy to simply snip out the deteriorating flowers, and grow the small perennials plants for their appealing succulent foliage until they bloom again. They do not get much more than half a foot tall, so can stay in small pots indefinitely. They seem to prefer the porosity of clay pots. Because they can rot, they should be watered when the surface of the soil seems to be getting dry, and their drainage saucers should not be allowed to hold water too long. Kalanchoes like bright but indirect sunlight. They can be acclimated to direct sun exposure, but might seem to be somewhat stunted. If brought in before frost, they can be happy out on a patio. The clustered small flowers can be white, pink, red or bright or pastel shades of orange or yellow.

Keep Vegetation Clear From Chimneys

51028thumbFireplaces simply are not what they used to be. Building regulations in many municipalities do not allow for the construction of new fireplaces, except only for pellet stoves. Fireplaces that get damaged by earthquakes are commonly removed instead of repaired. Now that urban sprawl has replaced so many of the rural areas and defunct orchards, firewood is more expensive, even if purchased from a tree service. When a tree needs to be cut down, no one seems to have the time to cut and split the wood.

Modern heating systems are so much more reliable, efficient and just plain easy. Their fuel can actually be less expensive than firewood, and is not nearly as polluting. There is no smoke to offend the neighbors. There are no potentially dangerous sparks. There is no dirty chimney that needs to be cleaned. There is no need for firewood occupying space in the garden. Yet, with all the advantages of other heating systems, many of who still have fireplaces like to use them now that the weather is getting cool.

Because so much heat and a few sparks go out through the chimney, it is extremely important to keep trees and vines away from the top of the chimney. Cypress, pines, cedars, large junipers, eucalypti and fan palms that are not groomed of their dried old leaves are very combustible. Vines like wisteria, bougainvillea, creeping fig and Boston ivy are not unusually combustible, but have a sneaky way of overwhelming chimneys and accumulating debris (and sometimes rat or bird nests!). Any vegetation will be combustible if it gets hot enough. Sparks from burning foliage above can easily ignite old fashioned cedar shingles.

Trees should also be pruned away from roofs, gutters, fences and anything else that can be damaged by the abrasive motion of the stems and foliage in the wind. Stems of deciduous trees lose weight as they defoliate, and may even lift off of roofs that they had been leaning onto just a few weeks ago, but should be pruned accordingly anyway. Branches that have been leaning on a roof for quite a while may have accumulated a bit more debris than would be expected. Gutters and downspouts should be cleared of debris before the rain starts, and may need to be cleared again later where deciduous trees fill them up through autumn and winter.