A Strong Foundation

P00628-1
Before: Camellias left the foundation exposed a long time ago, but instead obscured the view from the windows above.

‘Foundation planting’, which most of us think of as vegetation intended to merely obscure a foundation behind lower and prettier plants, has a simple utilitarian origin. Before homes were so commonly outfitted with rain gutters like they are now, densely shrubby foundation plantings diffused water that fell from eaves, and limited splattering of mud onto foundations and walls.

Nowadays, foundation planting only needs to look good, and maybe obscure crawlspace vents or exposed undersides of decks. They might be allowed to get as high as window sills, or higher.

These camellias got more than a bit too high. They had not obscured the cinder block foundation in a very long time, and did not contribute much to the shingled wall above. What was worse was that all of their best foliage and bloom obscured the view from the window above, and obstructed sunlight to the interior. They were impressive specimens, but were not doing their job.

We tried to prune their canopies lower and thinner, in order to promote more lower growth that we could prune down to later. They responded by merely replacing what was pruned away, exactly where it was pruned away from. We considered relocating the camellias to where such big and lanky camellia trees would be desirable, but they are too old and firmly rooted in place.

P00628-2
After: Camellias can either start over or die.

The only option was to coppice them. It was quick and easy. We cut them to the ground with the expectation that they will either regenerate from their stumps or die. If they die, we will not miss them. (Okay, I might.) The new growth will obscure the foundation well, and after a few years, should resume blooming. They will be patchy if some but not all do survive, but we tried.

The remaining sculptural specimen obscures no windows.

P00628-3
Stumps are a few inches high. Any new growth should hopefully develop on top, just above grade.

Silver Lining

P00614-1
This little silver dollar tree did well with a second chance.

Among the more than seven hundred species of Eucalyptus, nomenclature gets confusing. It certainly does not help that some species have multiple common names. Eucalyptus cinerea is a rather distinctive species with at least two equally distinctive common names. The problem with these names is that, although sensible in Australian, they are not so sensible to Californians.

‘Mealy stringybark’ is a name that must describe something of the physical characteristics of the species. The bark is rather stringy, but no more stringy than that of so many other species. The glaucous foliage might be described as mealy in Australian English. ‘Argyle apple’ is a weirder name. Again, it must make sense in Australian culture. I just know it as ‘silver dollar tree’.

A few years ago, I acquired a severely disfigured and overgrown #5 (5 gallon) specimen of silver dollar tree, along with three comparable specimens of dwarf blue gum, Eucalyptus globulus ‘Compacta’. They were about to be discarded from the nursery where I found them. They got canned into #15 cans, and coppiced back to their distended lignotubers. All regenerated nicely.

Two of the blue gums found appropriate homes. One remains here, and was coppiced again last year. The silver dollar tree stayed late too, but happened to get planted into a landscape last autumn. It is developing into such an appealing tree that one would not guess that it had experienced such neglect and subsequent trauma. The exemplary silvery gray foliage is so healthy.

As it regenerated after getting coppiced, the strongest of the new stems was bound to a stake to form a single straight trunk. All smaller basal stems were pruned away after the first season. The little tree cooperated through the process, and now lives happily ever after. I still do not know its name.

P00614-2
Silver dollar tree produces strikingly silvery foliage.

Redtwig Dogwood

00219
Colorful bark for the wintry landscape.

Most dogwoods are popular for spectacular white or pink spring bloom prior to foliation. Redtwig dogwood, Cornus sericea, is an odd one though. It is a ‘dog’wood that is appropriately grown for colorful twig ‘bark’. It blooms later than other dogwoods, and after foliation. The one to two inch wide trusses of tiny pale white flowers lack the flashy bracts that make other dogwoods so colorful.

Another difference is that, unlike more familiar dogwoods, redtwig dogwood naturally grows as a shrubby riparian thicket rather than as a small tree. Long limber branches can grow to more than fifteen feet high only by leaning into other trees or shrubbery. In home gardens, they typically get coppiced or pollarded just before foliating in spring, to develop twiggy growth for color next winter.

After a bit of autumn chill and defoliation, young stems of well exposed wild redtwig dogwood are a delightful glossy ruddy brown. Twigs of garden varieties are richer cinnamon red, rusty orange, soft yellow, orange blushed pale yellow, or yellowish green. Color is subdued by shade. Some cultivars have variegated foliage. Autumnal foliar color is more impressive in more severe climates.

Pollarding And Coppicing Appall Arborists

00212thumb
Pollarding is disturbingly severe but effective.

Very few arborists in America condone the extreme pruning techniques known as pollarding and coppicing. Both techniques essentially ruin trees, and deprive them of their natural form. Affected trees likely require such procedures to be repeated every few years or annually. Otherwise, they are likely to succumb to resulting structural deficiency. Restoration of such trees is rarely practical.

Pollarding is severe pruning to remove all except the main trunk and a few or perhaps several main limbs. Coppicing is even more severe, and leaves only a stump. Both are done while subjects are dormant through winter. Most or all new growth that develops is spring is concentrated around pruning wounds of the previous winter. Some coppiced stumps generate growth from the roots.

If pollarded or coppiced annually, all growth that developed during the previous season gets pruned cleanly away to where it grew from since the previous procedure. Distended ‘knuckles’ develop at the ends of pollarded limbs or coppiced stumps as the pruning is repeated for a few years. ‘English’ pollarding leaves a well oriented stub of any desired length to slowly elongate each knuckle.

Pruning wounds should be as flush to each knuckle as possible, without intrusive stubble. The many small pruning wounds left on each distended knuckle will compartmentalize (heal) efficiently as new growth develops during the following season. Pruning below a knuckle might seem to be more practical, but leaves a single but big wound that could decay before it gets compartmentalized.

Delaying pruning for a few years creates bigger wounds, and allows innately structurally compromised stems to get heavy.

Pollarding and coppicing were developed a long time ago to produce kindling, fence stakes, cane for basketry, and fodder for livestock, as well as silkworms. Nowadays, it is done to contain big trees, enhance the size and color of leaves, produce juvenile foliage, produce colorful twiggy growth, or prevent unwanted bloom or fruit. Not many trees are conducive to such severe techniques.