Prickly thickets of California wild rose, Rosa californica, are not often much to look at, even while adorned with small and sparse pink roses in spring and summer. The fragrant flowers can actually range in color from white to rich pink, and may have more petals, but are not abundant enough to be very impressive at any one time. In autumn though, all the flowers that bloomed in the previous few months leave bright orange or red fruiting structures known as ‘hips’, that linger on the bare canes through winter.
The rose hips of California wild roses had historically been used to make herbal tea because they contain so much vitamin C and have a pleasant flavor. (California wild rose is a ‘tea’ rose but not a hybrid ‘T’ rose.) They can also be made into jelly or sauce. The only problem is that birds like them too, so often take them before anyone else has a chance to.
Of the few native species that share the same designation of ‘red willow’, Salix lasiandra, is likely the most common locally. However, it has a few other common names, including shining willow and Pacific willow. For those acquainted with it, recognition is easier than nomenclature. It is not a problem though, since red willow is rarely an intentional choice.
Red willows, including less common species, grow wild in local riparian situations. They sometimes sneak into home gardens, particularly if irrigation is generous. Their rampant growth is susceptible to spontaneous limb failure. Pruning can compensate for structural deficiency of young trees. However, trunks typically succumb to decay within thirty years.
Mature trees are mostly less than thirty feet tall, typically with low branches, and possibly with a few elegant trunks. The gray or light brown bark is finely furrowed. The deciduous foliage has a slight sheen, and then turns brownish yellow prior to autumn defoliation. Its narrow leaves are about three inches long. Twigs are yellowish or green rather than red, as it implies.
Gardening is quite unnatural. It involves unnatural cultivation of mostly unnaturally exotic (nonnative) species of plants. Irrigation delivers more water than seasonal rain provides. Fertilizers contribute more nutrients than endemic soils provide. Pesticides, if necessary, inhibit proliferation of pathogens. Nature simply could not accommodate such demands.
Not only is gardening unnatural, but it also interferes with established ecosystems. Many aggressively invasive plants were formerly desirable exotic plants that naturalized. Many pathogens arrived with exotic plants. Several naturalized plants have potential to distract native pollinators from native plants that rely on their pollination. It is an ecological mess.
Nonetheless, it works. Gardening within the constraints of nature would be unproductive. Most residents of California inhabit chaparral or desert climates that originally sustained limited vegetation. Such limited vegetation sustained a very limited indigenous populace within relatively vast areas. Modern residential parcels would be completely inadequate.
That is the justification for gardening, whether for sustenance, or merely to beautify home environments. Unnatural breeding continues to improve performance of many useful and appealing plants. Unnatural horticultural techniques generate more desirable vegetation within confinement of urban gardens than would naturally inhabit a few acres in the wild.
Nature remains relevant though. All plants originated within nature somewhere. Besides their basic requirements, exotic plants prefer environmental conditions that are similar to those of their natural origin. Some tropical plants crave more warmth and humidity. Some plants prefer more winter chill. Most popular exotic plants rely on supplemental irrigation.
Physical characteristics of many plants necessitate special accommodations also. Roots of plants that naturally compete in dense jungles are likely to damage pavement. Without adequate pruning, native plants that naturally exploit burn cycles can become perilously combustible. Many vines naturally try to overwhelm nearby vegetation and infrastructure.
Native plants like coast live oak, valley oak, toyon, flannel bush, Western redbud and California lilac (ceanothus) are among the most resilient of plants as the weather gets dry and warm after spring. So are plants from similar climates, like bottlebrush, oleander, rockrose, grevillea, acacia and eucalyptus. They survive dry summers by dispersing their roots deeply into soil that does not get as desiccated as surface soil naturally does (without irrigation).
Ironically, these most resilient plants can also be difficult to work with while they are young. Because they rely on extensive root dispersion for survival, new plants that have not yet dispersed their roots can not survive long without regular watering. They only become tolerant to drought as their roots disperse into deeper soil.
However, because they are adapted to arid conditions, they do not like to be too damp for too long. Roots soon rot in soil that does not drain adequately between watering. They therefore need to be watered frequently, but not too frequently. Yes, that is as confusing as it sounds.
To make it even more confusing, these plants will need less watering as they mature and disperse their roots. Bottlebrush, oleander, contoneaster, hop bush, firethorn, grevillea and juniper can certainly tolerate more water than they really need; but wasting water is contrary to selecting drought tolerant plants to conserve water. Manzanita, coyote brush, rockrose, flannel bush and redbud may actually succumb to rot if watered too much. Even perennials like Pacific coast iris and yarrow can have problems.
Pine, oak, acacia and especially eucalyptus disperse their roots as soon as they can, so do not want to be confined in containers. It is therefore best to plant smaller young specimens than larger ones. #5 (5 gallon) eucalypti get established in the garden more efficiently than larger but more expensive #15 (15 gallon) trees. If #1 trees were available, they would be even better.
Its plump and inch-long acorns are misleading. Tanoak, Notholithocarpus densiflorus, is not actually an oak. Otherwise, it would be a species of Quercus. Regardless, its wood is potentially as practical for furniture and flooring as wood of other oaks. It also works very well as firewood. Historically, tanoak bark was useful for tanning leather, hence its name.
Although native and somewhat common in some coastal forests, tanoak is almost never a choice for intentional planting. Those that inhabit home gardens likely either grew from acorns, or were there prior to development of the landscapes. Young trees can grow fast to more than forty feet tall, typically with conical form. Mature trees might get twice as tall.
Tall trunks of tanoak are elegantly upright, and eventually develop lofty branch structure. Their gray or brownish bark is handsomely furrowed. The somewhat leathery evergreen foliage produces potentially objectionable tomentum. The dentate leaves are two to four inches long. Sadly, tanoak is very susceptible to Sudden Oak Death Syndrome (SODS).
Exotic plant species that appreciate endemic climates and soils seem like they should be the next best options to native plant species. A few unfortunately naturalize aggressively enough to displace native plants species, and interfere with the natural ecosystem. A few can not naturalize without their preferred pollinators that did not come with them from their origin. Some have potential to naturalize, but either refrain, or are civil about doing so. Some that are invasive within landscapes are not as invasive in the wild, particularly if they need more water than they get from local weather. I occasionally find exotic plant species, including a few that I am surprised to find.
1. Sticky monkey flower is the ‘+1’. It is the only one of these six that is native rather than exotic. Its odd name leaves one pondering how a monkey is involved and why it is sticky.
2. Mock orange seems to be naturalized, but contrary to common belief, may actually be native. A single flowered variety and a double flowered variety may be different species.
3. Jupiter’s beard is most certainly exotic and naturalized, but does not seem to be polite about it. It can get quite invasive. However, it does not get far from irrigated landscapes.
4. Iris remains a mystery to me. I grew this same seemingly simple species while in high school, but have never identified it. It naturalizes, but only where it gets sufficient water.
5. Spanish lavender is obviously not native since it is from, well, Spain. It can naturalize, but is not aggressive about it. The honeybee is much more aggressively naturalized here.
6. Crinum, like the Iris, is unidentified. I am not even sure if it is a Crinum. It grows wild with sticky monkey flower, in sandy soil that gets dusty, dry and warm through summer.
There is no way to say it delicately. Flannel bush, Fremontodendron californicum, is not easy to work with. It grows rapidly and rampantly with awkward form to about ten feet high and broad, but then starts to deteriorate when only about twelve years old. It can deteriorate even sooner if well irrigated. The fuzz on the foliage and young stems is irritating to the skin, especially during warm weather, so is very uncomfortable to handle. Otherwise, for out of the way spots, flannel bush is a striking native plant with impressively abundant bright golden yellow bloom this time of year. Neglected plants that do not get pruned or watered seem to be happier and more colorful, and can get older and much larger.
Valley oak, Quercus lobata, and Coast live oak, Quercus agrifolia, which I featured here last week, are the two formerly prominent native oaks of the Santa Clara Valley. I do not know if valley oak is native to the Santa Cruz Mountains above the Santa Clara Valley. It should be; and I should know for certain. However, I am not convinced. It is a chaparral species, not a forest species. The several old specimens in the Santa Cruz Mountains are on roadsides and in other situations where they seem to have been planted intentionally. Yet, this region developed mostly after the Great Earthquake of 1906, and not much was here prior to that, but some of the valley oaks seem to be a few centuries old.
1. A different perspective of the same valley oak from last Saturday conceals major storm damage that is otherwise so prominent. This really is a grand tree, in a perfect situation.
2. Although this is not a good picture, and does not seem to show much, it demonstrates how this tree is squarely centered within this view from the old depot baggage platform.
3. From the opposite side, the trunk obscures the baggage platform. Was it planted there intentionally? If so, why was it not centered on the window or doorway of the old depot?
4. It is just coincidence that the tree is situated so ideally on the edge of an area that was formerly used for parking? It was already old when cars still had horses in front of them.
5. Valley oak is such a grand tree. As big and sculptural as this specimen is, it is perhaps a century or so younger than the other tree. It was still quite small and shrubby in 1906.
6. Even the leaves are distinguished. The leaves of the trees in my former neighborhood had rounder lobes and sinuses. I do not know if such traits are environmental or genetic.
This is the link for Six on Saturday, for anyone else who would like to participate:
With such a weird name, beard tongue is probably less commonly known by its common name than by the Latin name of Penstemon. Of the thousands of cultivars (cultivated varieties) that have been developed over the decades, most of those that are popular for home gardens are known as cultivars of Penstemon gloxinioides, even though their actual lineage is generally unknown. In recent years, other species have become more available.
Spikes of red, pink, purple or white flowers stand vertically above the foliage. Yellow flowers are still rather rare. Individual flowers are bisymmetrically tubular, with two conspicuous lips and a fuzzy tongue. Some beard tongue have relatively wide leaves and plump flowers, like really big snapdragons. Others have narrow leaves and thin flowers. Mature plants get only 1 to 2½ feet high and a bit wider, although some of the rare specie can get significantly larger.
On the West Coast between British Columbia and Mexico, the largest native fern might be the giant chain fern, Woodwardia fimbriata. In sheltered and damp coastal forests, it can get taller than six feet, although it is typically about three feet tall and wide in home gardens. The lightly colored and almost yellowish green fronds generally stand upright and flare outward from the center. The foliage is doubly lobed and lacy, but quite substantial. The thick rhizomes spread rather slowly. Established plants are remarkably resilient. They can tolerate almost full sun exposure if watered enough. Those in partial shade can tolerate lapses of watering. However, they do not recover too readily from relocation or division.