Deciduous Foliage Is Efficient

Maple foliage only seems to be messy because it all falls at once.

(Horridculture will resume on Friday.)

Contrary to popular belief, most deciduous trees, those that drop all their leaves in autumn, are not as messy as most evergreen trees. There are of course a few exception; such as cacti that lack foliage completely, or Italian cypress that drop their finely textured foliage straight down within a very narrow drip-zone, where it decomposes and disappears unnoticed. Very few leaves fall from a big silver maple through winter, spring and summer, so that almost all of the raking is done when almost all the leaves get shed in autumn. However, a big Southern magnolia generally drops leaves throughout the year, so that raking is always necessary.

The problem is that when deciduous trees get to be messy, they are very messy. Also, they get to be messy at the worst time of year, when their leaves mix with rain to clog drains and gutters. Unraked leaves become hazardously slippery when they get wet and start to decompose. It is amazing how something that can be so appealingly colorful through autumn can so quickly become such a nuisance.

Leaves of deciduous trees somehow seem to be better for composting than those of some of the evergreen trees. Anyone with a Southern magnolia knows how slow the foliage is to decompose. Foliage of camphor, bay, carob and various eucalyptus certainly decompose slower than various maple, ash, poplar and birch. Many of us outfitted with green waste bins or curbside collection of green waste prefer to recycle the less desirable evergreen foliage, and compost primarily deciduous foliage. Those of us who do not compost but need to rake under large or many deciduous trees may fill bins for several weeks, or leave very big piles of leaves at the curb.

Small leaves, such as those of most elms, or finely textured compound leaves, such as those of silk tree, jacaranda or locust, may not need to be raked if they fall onto lower shrubbery or ground cover. Small leaves or the small leaflets of disintegrating compound leaves simply sift through the lower plant material to decompose below. However, large elms may produce such an abundance of foliage that some may need to be removed. Maple and other large leaves are not so easy to ignore. They can shade lawns, ground cover or bedding plants, so need to be raked as they fall.

Wise Old Owl (2011)

There is more to cut flowers than flowers.

(This is an old article from 2011, so much of the information within is no longer relevant.)

The sixteen acres of gardens of Filoli are spectacular and horticulturally compelling throughout the year. However, the weather through winter, although more pleasant than other places in the world, is not always quite so compelling or conducive to garden tours. At Filoli though, this is not a problem. More than six hundred volunteers and the Filoli staff merely bring the outdoors indoors, by selecting materials from the garden to adorn the interior of the 36,000 square foot Filoli residence for ‘The Wise Old Owl’, the annual fund raising Holiday Traditions Boutique.

While perusing The Wise Old Owl merchandise, guests can enjoy how so much more than flowers can be brought in from the garden to deck out the home. Bare stems, gnarly limbs, evergreen foliage, pine cones, bark and all sorts of bits and pieces of the autumn and winter garden demonstrate the potential for alternatives to traditional cut flowers that we may not even recognize as useful materials in our own gardens. Of course, there will be no shortage of the less abundant flowers that bloom through the season and decoration that are not out of the garden, as well as live music to enhance the display. Regardless of horticultural interest or boutique merchandise, the grand residence at Filoli is worth visiting even on the least eventful day of the year.

There are too many events within the Event to describe here. Guests can visit http://www.filoli.org to plan ahead and make reservations for buffet lunches and evening bistro dining, as well as an elegant Saturday Evening Dinner Party with dancing in the Ballroom. Children six to twelve years of age can enjoy a Children’s Tea on the finale of The Wise Old Owl on December 3.

The Wise Old Owl begins in only a few days on November 25, and continues through December 3. The hours of operation and admission are variable relative to the various events throughout the main Event. Reservations for specific events can be arranged and more information can be found online

Tickets can be purchased online, by fax or by telephoning Filoli weekdays between 9:00 a.m. and 4:00 p.m. At 650 – 364 8300 X 508. Order forms for fax transactions can be downloaded from the website and sent to 650 – 503 2090. Admission is limited; and tickets get exhausted somewhat early. Tickets are neither refundable nor exchangeable. Filoli is located at 86 Canada Road in Woodside (94062).

Defoliation Is A Messy Process

Defoliating deciduous foliage must go somewhere.

Autumn foliar color eventually gets messy. Actually, any deciduous foliage can become messy during its autumn defoliation. Color is not a prerequisite. Some deciduous foliage remains green through the process. Furthermore, some evergreen foliage contributes to the mess. A few evergreen species shed a bit more as the weather becomes more wintry.

Contrary to popular belief, deciduous vegetation is neater than evergreen vegetation. It only seems to be messier because it defoliates completely at once. Also, such complete defoliation exposes bare stems. Evergreen vegetation sheds slower throughout the year. As it replaces old foliage with new, it sheds more in seasonal phases, but incompletely.

Deciduous leaves also seem to be messier because they are generally bigger. They do not disintegrate into landscapes as efficiently as tiny evergreen leaves do. They require raking from lawns, as well as groundcover that can absorb smaller leaves. So, they fall most abundantly, and dissipate least efficiently. That is why defoliation is so very messy.

Defoliation of deciduous foliage occurs at both the best and worst time of year. It allows more warming sunlight into homes and gardens while the weather is cooling. It leaves deciduous trees more resilient to eventual windy wintry weather. However, it gets messy while the weather begins to get less conducive to gardening. Summer is about finished.

It truly is ironic. Rain and wind will eventually dislodge the last deciduous foliage during winter. Rain is also why this same foliar debris must not clog eavestroughs and gutters. Yet, it is why removal of such debris can be such an unpleasant chore. Removal of foliar debris from hardscapes is also important. It stains and gets slippery if dampened by rain.

While defoliation decreases shade above, it can increase shade below. Accumulation of foliar debris can detrimentally overwhelm turf and groundcover. Some large leaves can do the same on top of dense shrubbery. Fungal pathogens proliferate within the dark and stagnant dampness below such debris. Shade from such debris inhibits photosynthesis.

Colorado Blue Spruce

Colorado blue spruce is densely evergreen.

Most trees behave very differently in cultivation than in the wild. Colorado blue spruce, Picea pungens, is naturally a grand tree. It slowly but surely grows almost a hundred feet tall in the Rocky Mountains. Locally, if not competing with taller trees, it rarely gets as tall as thirty feet. Mild winter weather does not stimulate much more than necessary growth.

Furthermore, most home garden Colorado blue spruce are densely compact cultivars. Most are plumply conical. A few are quite rounded or globular. They function more as big shrubbery than trees. They are less conducive to major pruning than shrubbery though. Removal of low limbs for clearance compromises their strict but naturally elegant form.

Foliar color is as appealing as form and foliar texture. Obviously, Colorado blue spruce should be blue. Some are a bit more silvery or grayish. Trees that grow from seed tend to be greener and a bit less dense than cultivars. Such seedlings are sometimes available online. The stiff and prickly needles of Colorado blue spruce are only about an inch long.

Deciduous Trees Are Not Necessarily The Messiest

This weird Euphorbia is one of the few small evergreen trees that drops no foliage.

Contrary to popular belief, most deciduous trees, those that drop all their leaves in autumn, are not as messy as most evergreen trees. There are of course a few exception; such as cacti that lack foliage completely, or Italian cypress that drop their finely textured foliage straight down within a very narrow drip-zone, where it decomposes and disappears unnoticed. Very few leaves fall from a big silver maple through winter, spring and summer, so that almost all of the raking is done when almost all the leaves get shed in autumn. However, a big Southern magnolia generally drops leaves throughout the year, so that raking is always necessary.

The problem is that when deciduous trees get to be messy, they are very messy. Also, they get to be messy at the worst time of year, when their leaves mix with rain to clog drains and gutters. Unraked leaves become hazardously slippery when they get wet and start to decompose. It is amazing how something that can be so appealingly colorful through autumn can so quickly become such a nuisance.

Leaves of deciduous trees somehow seem to be better for composting than those of some of the evergreen trees. Anyone with a Southern magnolia knows how slow the foliage is to decompose. Foliage of camphor, bay, carob and various eucalyptus certainly decompose slower than various maple, ash, poplar and birch. Many of us outfitted with green waste bins or curbside collection of green waste prefer to recycle the less desirable evergreen foliage, and compost primarily deciduous foliage. Those of us who do not compost but need to rake under large or many deciduous trees may fill bins for several weeks, or leave very big piles of leaves at the curb.

Small leaves, such as those of most elms, or finely textured compound leaves, such as those of silk tree, jacaranda or locust, may not need to be raked if they fall onto lower shrubbery or ground cover. Small leaves or the small leaflets of disintegrating compound leaves simply sift through the lower plant material to decompose below. However, large elms may produce such an abundance of foliage that some may need to be removed. Maple and other large leaves are not so easy to ignore. They can shade lawns, ground cover or bedding plants, so need to be raked as they fall.

Juniper Cultivars Deserve More Consideration

Evergreen juniper foliage has distinctive texture.

Fads come and go. Many can be good, even if only briefly. A few might be bad enough to later stigmatize the object of the fad. For example, the formerly esteemed crape myrtle is now familiar as a mundanely common tree. Flashy bloom and complaisance contributed to its excessive popularity. Most sorts of juniper are similarly victims of their previous fad.

A few cultivars of juniper suddenly became overly popular during suburbanization of the 1950s. They were remarkably reliable and resilient. Most were shrubbery or low hedges. A few were groundcover. Hollywood juniper grew as a compact sculptural tree. However, most junipers grew too big. They became difficult to maintain, or impossible to renovate.

As many outgrew suburban gardens, few junipers outgrew their reputation. Even modern cultivars that were unavailable during the fad of the 1950s are perhaps less popular than they should be. Realistically, many old and new cultivars of juniper are quite practical for refined home gardens. They merely need to be appropriate to their particular application.

Many cultivars of several species of Juniperus are commonly available. Straight species are very rare from nurseries, although a few are native nearby. All junipers are evergreen with tiny awl or scale leaves. Foliar color ranges from forest green to silvery gray. Bloom is unremarkable. Some junipers produce pretty and aromatic blue, gray or black berries.

Junipers generally do not respond favorably to pruning that damages their natural forms. Those that grow as groundcovers, with stems that sprawl over the surface of the soil, are not offended by pruning to contain their edges. However, most groundcover junipers are actually just low shrubbery. Pruning might leave holes within their dense foliar canopies.

Junipers that grow as small trees do not mind removal of lower limbs at their main trunks, but object to partial pruning or ‘stubbing’ of such limbs. Regardless of their natural forms, all junipers should be proportionate to their particular applications. With sufficient space, they can mature and develop their naturally distinguished forms with minimal altercation. Maintenance could really be quite minimal.

Evergreen Foliage Has Distinct Advantages

Evergreen foliage is shady all year.

Gardening was easier before suburban lifestyles became so passe. Now, larger modern urban homes occupy smaller urban parcels. Modern fences are taller to enhance privacy for such densely situated homes. Garden space is both minimal and shaded by so much infrastructure. Ironically, shady evergreen foliage is now more practical for such gardens.

Deciduous trees are still practical for single story suburban homes on suburban parcels. They provide cooling shade for summer, and allow warming sunshine through for winter. Smaller evergreen trees and shrubs closer to fences obscure unwanted scenery beyond, without shading homes during winter. Such strategy is facilitated by sufficiency of space.

It is not so practical for confined and modern urban gardens though. Space is insufficient for big deciduous shade trees. Smaller trees can not get tall enough to shade roofs of tall modern homes. Insulation of modern homes is fortunately so efficient that summer shade and winter sunshine are not as advantageous as they still are for older suburban homes.

Therefore, most trees in modern home gardens primarily obscure unwanted scenery and provide privacy, rather than merely provide shade. Not only should they be proportionate to their gardens, but such trees should also retain evergreen foliage as low as the tops of associated fences. Some of the more practical options are actually evergreen shrubbery.

Large evergreen trees, such as Southern magnolia, California pepper, camphor, various palms and some eucalypti, are too big for some confined modern home gardens. English laurel, New Zealand tea tree, hopseed bush, various arborvitae, and particularly various pittosporum function as small evergreen trees that are proportionate to confined gardens.

As practical as evergreen foliage is for modern urban home gardens, it requires as much maintenance as other forms of vegetation. Contrary to common belief, evergreen foliage sheds. It is just sneaky about doing so slowly throughout the year. Additional foliage also innately adds shade to already shady situations, which can complicate other gardening. To become compact evergreen trees, shrubbery requires directional pruning.

Evergreen Tendencies Are No Mistake

Evergreen foliage is resilient through winter.

Evergreen plants retain foliage throughout the year. Deciduous plants defoliate for part of the year. That is the simplest explanation. The various reasons for shedding or retaining foliage are not so simple. Annual plants die after their single growing seasons. They can not live long enough to be either evergreen or deciduous. Some plants just may be both.

Foliar color, to some extent, conforms to preferable environments. Monterey cypress and Monterey pine have richly deep green foliage. It maximizes absorption of sunlight within the foggy coastal regions that the trees inhabit. Blue spruce has glaucous bluish foliage. It reflects a bit of sunlight to protect from sun scald within severe high mountain climates.

Similarly, deciduous plants generally defoliate for environmental situations. Most go bare for winter, in order to be less susceptible to damage from wind and snow. Bare stems do not collect as much heavy snow as foliated growth. They are also less resistant to wintry winds. If foliated, they are more likely to succumb to wind or overburdening snow weight. 

Evergreen plants may retain their foliage because they are from climates in which winter weather is not so harsh. Wind may be no more extreme than it is in other seasons. Snow may never occur. Plants from tropical regions may be unfamiliar with colder weather and shorter daylength associated with winter. Their evergreen foliage might function all year.

Some tropical plants that are evergreen within their native environments may defoliate or die back as a result of even mild frost. Some recover as if deciduous. (Those that can not survive local climate conditions are not very popular here.) For example, canna die back to the ground after frost, but regenerate later. In tropical climates, they can be evergreen.

Evergreen species from mountainous regions or extreme northern latitudes are generally uncommon here. They prefer harsher weather. Although evergreen, they are remarkably resilient to wind and snow in the wild. They are likely evergreen to always stay receptive to limited sunlight whenever it is available, though wintry weather is possible at any time. 

Evergreens Make A Mess Too

Big evergreen trees make big messes.

Nature is messy. It is that simple. Leaves, flowers, fruits and stems regularly fall from vegetation onto the ground. Animals contribute their mess too. Insects and microorganisms seem to eliminate most of the mess. In reality, they merely accelerate the process of recycling the mess back into more mess. Decomposing organic matter sustains viable vegetation as it perpetuates the process.

Natural mess serves many other purposes as well. It really is an important component of ecology. It retains moisture and insulates the soil. Many plants drop foliage that inhibits the germination of competing plants. Many merely smother competing plants with their mess. Several, particularly locally, produce combustible debris to incinerate their competition in the next convenient forest fire!

Obviously, the sort of mess that is so beneficial in nature is not so desirable in home gardens. Even if weed suppression and moisture retention are appealing, combustibility is not! Neither is any mess that vegetation deposits onto hardscapes, roofs or lawns. Such mess becomes more apparent as deciduous trees defoliate this time of year. Most produced no other mess since last year.

As messy as deciduous trees are, they are generally no messier than evergreen trees. They just happen to defoliate within a very limited season, rather than throughout the year. Some evergreen trees shed more in a particular season, typically as new foliage replaces the old. Otherwise, they shed slowly and persistently throughout the year. The mess seems like less, but is just prolonged.

Both evergreen and deciduous trees serve their respective purposes. Evergreen trees obscure unwanted scenery all year. Deciduous trees provide cooling shade for summer, and allow warming sunlight through for winter. The misconception that deciduous trees are necessarily messier should not exclude them from home gardens. Deciduous trees are often the most appropriate options.

Every species and cultivar of tree is unique. Many deciduous trees actually are messier than some evergreen trees. However, most are not.

Aleppo Pine

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Aleppo pine thinks it is native.

From coastal regions around the Mediterranean Sea, the Aleppo pine, Pinus halepensis, came to be right at home on and near the coast of California. Once established, it can survive quite happily on rainfall. Trees that get too much water can actually get too heavy with foliage, and may eventually get disfigured if limbs break.

Shade under an Aleppo pine is not too dark. The light and sometimes yellowish green foliage is rather wispy, comprised of thin paired needles that are about three inches long. The sculptural trunks almost always lean to one direction or another, and often divide into multiple trunks once they grow out of reach. Bark is light gray with light brown striations.

Young trees can get big rather fast. They tend to be somewhat conical, or at least upright, until they get to be about forty feet tall. Then, they tend to shed lower stems and develop irregular branch structure with rounded tops as their growth rate slows. Only a few old trees in ideal situations slowly get to seventy feet tall. Seedlings sometimes appear where they are not wanted.