Conformity Is No Simple Task

Patching bald spots within Iris moss with Scottish moss might look . . . odd.

A combination of modern horticultural apathy and too many choices was probably the demise of conformity in home gardens. Formal hedges or even informal screens of several of the same plants are nearly obsolete. Ironically, long and low barrier hedges and so called ‘orchards’ of identical trees planted in regimented rows or grid patterns have become common in large landscapes in public spaces.

Those of us who still crave formal hedges, paired trees or any such symmetry in our home gardens must be more careful with the selection of the plants that need to conform than would have been necessary decades ago when there was less variety to complicate things. It is just too easy to get different varieties of the same plant. Only plants with matching cultivar (cultivated variety) names will necessarily match. (Yet, on rare occasion, even these are inaccurate.) For example, ‘Emerald’ arborvitaes will match other ‘Emerald’ arborvitaes, but will not match ‘Green splendor’ arborvitae, no matter how they resemble each other in the nursery.

Plants that are identified by their characteristics instead of by cultivar name are riskier. Blue lily-of-the-Nile could be any one of many different cultivars with blue flowers. It is therefore best to obtain all lily-of-the-Nile for any matching group from the same group in the same nursery at the same time. What will be available next week may actually be a different variety with a different shade of blue and different foliar characteristics. Nurseries bring stock in from so many different growers.

Adding new plants to replace those that have died within established hedges or streets flanked with the same trees can be particularly difficult, especially if the old varieties are no longer available. The old fashioned yellowish Japanese boxwood that was so common for small hedges in the 1950’s has not been common in nurseries for several decades. Replacement plants are darker green. Some are even compact cultivars or different specie like English boxwood. When lined up and shorn together, they make ‘calico’ hedges.

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Cultivars Are Merely Cultivated Varieties

Cultivars are distinct within their species.

Nomenclature is simply the technique of naming. Botanically and horticulturally, it is also a precise method of classification. Large classifications divide into smaller and exclusive classifications, which likewise divide. Botanical families divide into many genera, which likewise divide into many species. Some species divide further into varieties or cultivars. 

For example, Schwedler maple is within the Sapindaceae family. This family divides into many genera including the maple genus of Acer. (Genera is plural of genus.) This genus divides into varied species, including the Norway maple species of platanoides. Norway maple divides into more cultivars, including ‘Schwedlerii’, which is the Schwedler maple. 

Therefore, the botanical name of the Schwedler maple is Acer platanoides ‘Schwedlerii’. Family names are omissible. Genus names justify capitalization. Species names do not. Both genus and species names appear in italics. (Incidentally, genera are more ‘genera’l than ‘speci’fic species.) Single quotation marks contain names of varieties and cultivars.

Varieties are, as their designation implies, variants of a species. Some are dwarf, like the dwarf pampas grass. Some bloom with atypical color, like the maroon Texas bluebonnet. Their variations are natural and at least somewhat inheritable. Cultivars are varieties that can not perpetuate naturally, so are reliant on cultivation. They are ‘cultiva’ted ‘var’ieties.

Some cultivars developed from breeding. Others are naturally occurring mutants that are desirable enough to perpetuate. Because their unique characteristics are not inheritable, perpetuation is artificial. Seed of cultivars that originated as mutants lacks any desirable mutation. Seed of extensively bred cultivars is genetically unstable, or may not be viable. 

Most cultivars therefore rely on cloning for perpetuation. Propagation by cutting, grafting, division, layering and tissue culture, generates genetically identical copies of an original. Although it is illegal to propagate patented cultivars for profit, most common cultivars are too old for patents. Many perennial cultivars, such as iris and canna, proliferate naturally. 

Cultivars Of California Native Plants

Some natives belong in the wild.

Native plants are obviously happy with local climates and soils. Otherwise, they would not be native. They had been living here long before the first landscapes. They survived without irrigation, fertilizer or any maintenance. Regional varieties adapted to regional environmental conditions. Some of such varieties became cultivars that are now familiar.
A variety is, more or less, a naturally occurring variant. Unnatural selection and breeding produced some varieties. Generally, varieties are genetically stable enough to replicate for at least a few generations. A cultivar is a cultivated variety. It is unable to replicate by natural processes, so propagates by cloning. All clones are genetically identical copies.
Most cultivars grow from cuttings. Some cultivars of exotic (nonnative) plants are grafts. (Not many natives are conducive to grafting.) Regardless of technique, propagation of all cultivars is vegetative (without seed). Seed of some cultivars can produce plants that are similar to the parents, but not indistinguishable. Some will likely be completely different.
Honestly, most native plants are not as appealing in home gardens as their cultivars are. Some are desert or chaparral plants, which can get scraggly through summer. Some are sparsely foliated with irregular branch structure. Like the majority of exotic plants, several native plants benefited from some degree of refinement. It is a fair aesthetic compromise.
This is partly why landscapes of native plants look nothing like forests or unlandscaped areas. The dense and strictly conical form of ‘Soquel’ redwood is very different from that of wild trees. ‘Carmel Creeper’ ceanothus is greener and more densely foliated than wild counterparts. ‘Ken Taylor’ flannel bush is likewise unnaturally dense, low and mounding.
The other primary reason that landscapes of native plants are so different from the wild is that they typically include species from other regions. Some of the penstemons that are popular as native plants throughout California are actually only native to the Siskiyous. Limiting landscapes to true regional natives would produce very different results.

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!

Horridculture – Bad Seed

P80317+California poppies are like no other wildflower. They are so perfectly bright orange, and look almost synthetically uniform in profusion, as if painted onto coastal plains and hillsides. They may be a bit more yellowish in some regions, or a bit deeper orange in others, but they are always bright and strikingly uniform.
Genetic variation is naturally very rare. I can remember hiking with my Pa up to the (lesser known) Portola Monument in the hills behind Montara, and finding a few pale white poppies, and even fewer pale purple poppies. It was like finding four leaf clovers! Genetic variants among California poppies are not quite as rare as four leaf clovers are, but finding a few of both white and purple was really strange. I never found a pink one though.
Nowadays, poppies can bloom in all sorts of shades and hues or orange, yellow, red, pink and soft purple, as well as creamy white. Some bloom with fluffy double flowers. Of course, all this variety is not natural. California poppies were bred to do this.
The potential problem with such breeding is that California poppy is naturally very prolific with seed. Any of these weirdly bred varieties could escape into the wild and interbreed with wild poppies, causing them to be more variable, and interfere with the ecosystem.
The problem is not just with California poppies. Many plants get bred extensively enough to interfere with how they behave in the wild if they happen to escape cultivation.
Fortunately for California poppies, the weird new varieties do not really get very far in the wild. The are not true-to-type, so revert back to their original bright orange in just a few generations, even without outside influence. If pollinators do not recognize their unfamiliar color and form, they are less likely to get pollinated to continue to tamper with the ecology. In fact, wild California poppies still have the advantage in that regard.
This yellow California poppy with an orange center is a second generation seedling, and is already halfway between the original yellow variety, and the wild orange.

Horridculture – Promiscuity

 

71206Nomenclature of the botanical sort was so much simpler back when we studied it back in the 1980s. It was intended to be like that. It was how the various specie of plants were identified and classified. There were certain rules that simply made sense. After ‘family’, plants were classified into general ‘genera’, and then further classified into specific ‘specie’. Some specie were further classified into ‘varieties’ and ‘cultivars’. (Cultivars are simply ‘cultivated varieties’ that need to be perpetuated by cloning because they are too genetically unstable to be true-to-type from seed.)

The genus name is always first. The species name is always second. Because they are Latin, they should be italicized. Any variety or cultivar names are last, not italicized, and in semi-quotations.

Back in the 1980s, there were a few specie that did not quite fit into such neat classification. Intergeneric hybrids (between two parents of different genera) were designated by an ‘X’ before the genus name, such as X Fatshedera lizei, which is a hybrid between Fatsia japonica and Hedera helix. Interspecific hybrids (between twp parents of different specie) were designated by an ‘X’ before the species name, such as Platanus X acerifolia, which is a hybrid between two different specie of the same genus of Platanus. Then there are different species that hybridize freely, but are still designated as separate specie, such as Washingtonia robusta and Washingtonia filifera, but that is another story.

Nowadays, with so much weirdly promiscuous breeding, it is difficult to know what specie or even genera some of the modern varieties and cultivars fit into. Consequently, species names are often omitted, and genus names are sometimes changed. It is getting difficult to know the differences between the two formerly distinct genera of Gaillardia and Rudbekia.

What is even sillier is that all this is happening while ‘sustainability’ and gardening for ‘bees’ are such fads. Weirdly bred specie . . . or whatever they are, are likely unable produce viable seed, so are just the opposite of sustainable. They only sustain their own marketability by ensuring the need for replacement. Some make no pollen for the bees that visit the flowers expecting to find some. Some make pollen of questionable nutritional value, or serve it in complicated flowers that might be difficult for bees to navigate.

There certainly are advantages to simplicity.71129

Apologies for the delay of posting ‘Horridculture’, which is normally posted on Wednesday. I was unable to write, so advanced the article that was intended for today to Wednesday, and finished writing this rant for today.

Oasis

P80630KWhat are they doing out there, in those two pots in the island of such a vast parking lot? It is hard to say from this distance. They are so isolated. They might be happy and healthy summer blooming annuals. They might just be weeds. They could be plotting World domination. Plants can do some weird things in isolation.

Mexican fan palm is the most familiar palm in Los Angeles. Some know them as skydusters because they are so tall and lanky, and do not seem to have anything better to do than lazily brush against the undersides of clouds as they float by. In Los Angeles, there are not many clouds to keep them busy, and there is not even much smog anymore. Mexican fan palms certainly do not make much shade, and because they are so tall, their little shadows land in neighbors’ yards. They are so tall that you might be able to see them from wherever you are merely by looking towards Los Angeles. Instead of getting Frisbees and kites stuck in their canopies, they collect satellites. When they drop one of their big leaves, it burns up in the atmosphere.

In their natural environment, Mexican fan palm lives in a large and mostly contiguous native range (areas) in which individual colonies are not isolated for too long. Pollen gets shared rather thoroughly. Trees are consequently very similar throughout the range. Slight genetic variation is only perceptible in regions such as Los Angeles, where various groups of trees are grown from seed collected from various regions of the native range.P80630K+

Sometime in the ancient history of the specie, a few individuals decided to leave the rest of the herd and go live in isolation out in the adjacent deserts. They could only survive where there was a bit of water, so they inhabited any oasis they could find. This might have happened as some trees migrated up canyons that had perennial creeks flowing through them only to have the lower portion of the canyon go dry as outflow from above decreased. Seismic activity within the region has a way of altering the outflow of springs. Anyway, these more reclusive palms eventually became a separate species, or subspecies, or variety, depending on the botanist providing the information. This separate species (or subspecies or variety) is now known as the California fan palm, or the desert fan palm. It thrives on the hot and arid desert air, but is not very happy in milder and more humid coastal climates. (I am sorry that I do not have a good picture at the moment.)

Unlike Mexican fan palm that lives in a big contiguous range, California fan palms lives in small isolated colonies where they can not share their pollen freely with other colonies. Over thousands of years, each colony adapts to its specific environmental conditions. Genetic variation within colonies is not perceptible, but is quite obvious in landscape situations where trees grown from seed from different colonies can be compared.

California fan palm is much shorter and stouter than Mexican fan palm. It does not need to compete with too many other specie out in the desert. The trunks are straighter, and the canopies are fluffier. Unlike the very informal and relaxed Mexican fan palm, it is an excellent palm for formal landscapes. It is the specie that flanks the famous Palm Driveway at the Winchester House in San Jose. The only stipulation for these formal installations is that all the palms must be grown from the same batch of seeds procured from the same colony.

Cultivars Are The Real Cloned Mutants

80516thumbIt is not science fiction. It involves neither ninjas nor turtles. Cultivars really are mutant plants that can only be propagated by cloning. The word ‘cultivar’ is a portmanteau (two words combined into a single word) of ‘cultivated’ and ‘variety’. Unlike other varieties of plants that can be perpetuated by seed, cultivars must be cultivated by unnatural techniques to maintain their genetic distinction.

For example, ‘Alamo Fire’ is a variety of Texas bluebonnets with maroon flowers. The original seed were collected from a few naturally occurring variants with maroon flowers, and grown into more plants with maroon flowers, which provided more seed. No seed was collected from those that bloomed blue. By repeating this process of selection a few times, the variety was developed.

The variety ‘Alamo Fire’ is now sufficiently genetically stable to perpetuate itself, which means that subsequent generations will also bloom with maroon flowers. However, a few blue flowers might bloom in any generation; and unless they are weeded out before producing seed, they will eventually dominate until the entire colony reverts from maroon back to the more genetically stable blue.

‘Meyer’ lemon is an example of a cultivar. It must be propagated vegetatively by cuttings, or perhaps grafted onto understock. In other words, it must be cloned. It is a genetically unstable hybrid of a lemon and an orange, so plants grown from their seed would be very different from the parent. Many hybrids are so genetically unstable that they are sterile, and unable to produce viable seed.

Many variegated or dwarf cultivars of all sorts of plants are not hybrids, but are mutants. It is common for some arborvitaes to produce ‘sports’, which are simply mutant growth that is somehow different from the original growth. If a sport has a desirable characteristic, such as densely compact growth, variegation, or golden foliage, it can be cloned as a cultivar. Just like ‘Meyer’ lemon, a dwarf golden arborvitae is very unlikely to produce genetically similar seedlings.

Sport

P80506Not just any sport; a witch’s broom sport! Remember the quidditch tournament of the first Harry Potter Movie? Well, it has nothing to do with that. You should not be watching such movies anyway.

This sort of ‘sport’ is merely a genetic variant growth. This particular sport happens to be known as a ‘witch’s broom’.

There is quite a variety of other sports.

Sometimes, a plant is going along minding its own business, when all of a sudden, it produces a stem with variegated leaves. Unlike the plain green leaves on the rest of the plant, the leaves on the sport are outfitted with white margins. In the wild, such a sport would probably not last long. Since it has less chlorophyll than the unvariegated foliage, it would grow slower, so would eventually be overwhelmed and shaded out by the more vigorous greener foliage. However, if someone happens to find this variegated sport, and determines that the variegation might be an attribute, it can be propagated as a new variegated cultivar of the species.

Sometimes, a plant is going along minding its own business, when all of a sudden, it produces a stem with bronzed foliage, or gold foliage, or leaves that are shaped differently from those on the rest of the plant. Perhaps new stems are more pendulous than they normally are. Sometimes, growth is more compact. It might even be rather stunted and disfigured, branching into a tuft of densely arranged twiggy stems known as a ‘witch’s broom’.

Such growth does not look like a witch’s broom for very long. As it grows, it develops into a densely shrubby mass that eventually gets too heavy to be supported. If the dense growth is appealing, it can be propagated as a new cultivar, like the dwarf Alberta spruce was reproduced from a witch’s broom sport of the common white spruce, or the pencil point juniper was reproduced from a witch’s broom sport of the common juniper (Juniperus communis ‘Compressa’).

This massive witch’s broom happens to be on a Douglas fir. It has been here for decades. It sure is ugly, but also interesting. It could be interesting enough to be reproduced.

Dingo

P80407K

Dogs and humans have been in a symbiotic relationship longer than history can document. Dogs naturally became more domesticated as humans did, and have been more or less selectively bred for a few thousand years.

Dingos are different. No one knows for certain how domesticated they were when they first came to Australia. They probably had been domesticated enough to come on boats with the first humans to migrate to Australia. After arriving in Australia, they became feral, although still symbiotically migrating with humans. They are now considered a native species of Australia.

Many species of plants have lived symbiotically with humans as well. As long as humans have been living with dogs, they have been domesticating and breeding plants. As plants were more extensively bred, they became more dependent on humans for their perpetuation. Some are so overly bred that they are sterile and unable to perpetuate without human intervention to propagate them vegetatively. Others, although unnaturally productive in regard to what humans want from them, are too weak or otherwise inferior to survive in the wild.

However, there are some extensively bred plants that escape their domestic lifestyles, and perpetuate feral descendants who retain some of the domestic characteristics of their extensively bred ancestors. They are not quite like naturalized plants that were merely imported in a more or less natural state from other regions, or those that naturalize and revert to a natural state. Characteristically, they are between wild plants and extensively bred and selected domestic plants. They have developed their own stable but feral lineage that can perpetuate in the wild.

For example, the purple leaf plum has been developed as an ornamental tree for a very long time. Several vegetatively propagated cultivars are now available. The ancestors were likely discovered as mutants with darker bronzed foliage. These primitive mutants were more or less genetically stable, and were likely able to perpetuate naturally. It is difficult to say for certain. From these ancestors, seedlings with even darker foliage were selected, and bred to find more seedlings with even darker foliage, and so on. Because of this selective breeding, purple leaf plum trees grown as domesticated ornamental trees now have darker foliage they would naturally in the wild. They are propagated vegetatively because some are so overly bred that they are sterile, and seedlings from those that can produce viable seed would be likely be more genetically stable, and therefore less genetically ‘developed’. This is why feral seedlings from purple leaf plums that can produce viable seed are not as dark purplish bronze as their parents. Seedlings from the seedling trees are even lighter bronze. They may never be completely green, but they will not be dark purplish bronze either. They are feral purple leaf plums, like dingoes.