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Shasta Lake

Shasta Lake is a large reservoir on the Sacramento River. It contains water for flood control and to generate electricity. Some of the water within is used for agricultural irrigation and, to a relatively minor degree, to supply regional municipal water.

It is a very common misconception that the volume of water within Shasta Lake is necessarily relative to ‘drought’ conditions. Low water level is supposedly indicative of a ‘drought’. High water level is supposedly indicative of ‘normal’ weather conditions, including adequate precipitation. This same misconception seems to apply to all reservoirs in California.

Well, after the rainiest winter since 1982 and 1983, Shasta Lake is still not full. The level fluctuates, so might have been full earlier, or might be full later, but regardless, is not presently full. Water must be released prior to expected rainy weather, which can still occur during spring, in order to accommodate more water to control flooding. Less water may be released as drier weather is expected. Shasta Lake could therefore be fuller or completely full for summer, when almost no rain is expected. The presently observed water level does not indicate deficiency of water any more than a potentially higher water level during summer indicates surplus.

Most of California has a chaparral climate. Some of California has a desert climate. Such climates are naturally dry through summer. It is quite normal. It does not constitute a drought. A drought is an unusually dry weather pattern. It is not so normal.

Contrary to popular belief, California is NOT in perpetual drought. Although droughts occasionally happen, they are not annual events. Dry weather that occurs annually every summer is normal climate. If there is a deficiency of water here, it is because there are nearly forty million people relying on a limited supply of water.

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Drought Tolerance Necessitates Root Dispersion

Extensive root dispersion enhances drought tolerance.

Fads certainly complicate gardening. Most are merely marketing tactics. Most are bogus. Many even contradict their justifications! For example, most new, trendy and supposedly sustainable plant cultivars are genetically weak because of extensive breeding. Drought tolerance likewise has potential to be a constructive fad, but is so commonly misapplied.

Incidentally, its terminology is somewhat inaccurate. Drought is an extended but unusual pattern of dry weather. Whether the duration is for one year, or many, it is not permanent. The dry weather that persists through summer locally is normal for the chaparral climate. It is therefore a normal characteristic of climate, rather than abnormal weather conditions.

Drought tolerance is therefore practical here as chaparral tolerance. Most plants that are drought tolerant are naturally endemic to chaparral regions or deserts. Many of the native species naturally exhibit remarkable drought tolerance. Once established, they might not require any more moisture than they get from annual rainfall. Some prefer dry conditions.

Drought tolerance should not imply that such plants are undemanding. In some regards, they are more demanding and less adaptable than plants that require frequent watering. Such plants rely on extensive root dispersion to procure the moisture they require within dry situations. Most do not adapt to confinement, even if watering is enough to cause rot.

Container gardening is therefore a fad that is incompatible with drought tolerance. It only uses less water for plants that use more water. Also, modern drip irrigation, which is very practical for plants that rely on irrigation, requires a bit more effort for plants that use less moisture. To not promote rot, emitters must move farther from main trunks as plants grow.

Many of the most sustainable and drought plants are old fashioned sorts that became too common years ago. Fortunately, some are regaining popularity again. Some of the more compact eucalypti are proportionate to modern gardens. Grevillea, bottlebrush, rockrose, juniper, rosemary, salvia, lavender and New Zealand flax are as drought tolerant as they had always been.

Posted on by tonytomeo · 6 Comments

Drought Tolerance Versus Container Gardening

Drought tolerant plants loathe root confinement.

There are probably just as many reasons to not grow plants in containers as there are reasons to justify container gardening. Some potted plants consume less water than they would in the ground, but only because their demand is proportionate to their limited size. They only want more water in the ground because they can grow larger.

The most drought tolerant of plants are actually the least practical for pots or even large containers. They tolerate drought because they efficiently disperse their roots so extensively. Since they can not adequately disperse their roots in pots, they rely on what they can get from a relatively limited volume of soil. However, even if watered generously, many drought tolerant plants simply can not produce enough finely textured roots to absorb enough moisture.

For example, eucalyptus trees want to begin dispersing their roots while very young. If confined, their long and wiry roots simply go around within their limited volume of soil, trying to find a way out. They can develop a few more fibrous roots than they typically would, but probably not enough to compensate for limited root dispersion.

Wild lilac (Ceanothus spp.), flannel bush, manzanita and smoke tree are not only sensitive to confinement, but have difficulty recovering from confinement if put into the ground after their roots have circled too much within a container. Pines and many other conifers are likewise sensitive to confinement, but some types can recover if the binding roots get severed before they go into the ground.

Plants with dense and fibrous roots are more adaptable to containers. Most succulents and common yucca are good choices. Ferns and some grasses also work nicely, but need to be watered rather regularly. Some types of arborvitae and juniper work better than larger coniferous evergreens. Some small bamboos can stay potted, but not larger types.

Annuals, compact perennials and many ground covers that provide color and fill in space around larger plants are naturally adaptable to container gardening, but their need for regular watering can not be denied. There simply is no practical way of combining container gardening and drought tolerance.

Posted on by tonytomeo · 4 Comments

Know The Time To Conserve Water

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Automated irrigation is certainly not perfect.

In the wild, plants take water when it comes as rain. Native plants and plants that are from similar climates might be happy to get almost all of their water through winter, and almost none through summer. However, lawns and many other plants want some degree of water through summer. This is why most landscapes are irrigated.

Obviously, irrigation is unnatural. The main disadvantage is that it uses water that must be taken unnaturally from natural sources, which are often, and are presently depleted. The advantages (even during a drought) is that irrigation can be applied where needed, as needed, and when it is most appropriate.

Irrigation systems can be designed to deliver more water to plants that need it, and less water to those that are less consumptive. Watering by hose can of course be similarly tailored to the plants. The volume of water applied can be increased through warm and dry summer weather, and decreased or discontinued through winter.

Automated irrigation can be set to operate very early in the morning when no one is likely to be out in the landscape. The water gets used when the need for water in the home is minimal, so fluctuation in water pressure should not be a problem. If it operates early enough, irrigation can finish before anyone gets out to see it.

Furthermore, early morning also happens to be the best and most efficient time to apply water. Less water evaporates while the air is cooler and more humid. Therefore, more water soaks into the soil. Evapotranspiration (evaporation from foliage) is a bit subdued, so plants cycle through their own moisture a bit slower.

Many plants can just as easily be irrigated in the evening. This would allow even more time for water to soak in before the sun comes up. However, the problem for some plants and lawn is that moisture lingering on foliage all night long can promote the proliferation of all sorts of fungal diseases, including mildew.

Drip and similar irrigation is still the most efficient, simply because water is applied directly, with minimal evaporation. Broadcast irrigation from lawn sprinklers, especially fine mist, is much more susceptible to evaporation. Water evaporates as it gets sprayed through the air, and as it lingers on any wet surfaces.

Posted on by tonytomeo · 14 Comments

Eucalypti Are Innately Drought Tolerant

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Distinctive foliage provided by red ironbark.

Drought is nothing new here. There could be plenty of rain next winter and for years afterward; but eventually, there will be another series of dry winters, prompting rationing all over again. Landscapers and big box garden centers continue with business as usual. It is up to us to manage our gardens responsibly. Besides native plants, aloes, yuccas, junipers and eucalypti are four groups of formerly popular, drought tolerant plants that are worthy of more attention again.

Eucalypti had gotten a bad reputation even before they became popular the last time around. Tasmanian blue gum, Eucalyptus globulus, that was planted so extensively for wood pulp and timber throughout California, is a huge and extremely messy tree. Yet, it is still the most familiar of the eucalypti.

Garden varieties of eucalypti are much more docile. Even though they drop their evergreen foliage and hard seed capsules throughout the year, they do so on a smaller scale. The tall and elegant lemon gum constantly sheds strips of bark like the Tasmanian blue gum does, but does not get big enough to be too overwhelming.

Because they are so undemanding, and some are somewhat messy, eucalypti are best in unrefined parts of the landscape, and away from lawn. Their mess is no problem over ivy or iceplant. They are happiest where other trees might be unhappy. Generous watering actually inhibits root dispersion, and can cause vigorous but structurally deficient stem growth.

Eucalypti innately prefer to be planted while very young, even from four inch or one gallon (#1) pots. Larger (and more expensive) trees, such as boxed trees, take so long to get established that they get passed up by faster growing tiny (and less expensive) trees. Because they are sensitive to confinement, eucalypti are unfortunately rare in nurseries.

The online catalog of Annie’s Annuals and Perennials, which is famous for excellently weird and undemanding plants, features lemon flowered mallee, red capped gum, silver princess gum, bell fruited mallee and fuchsia gum, all in four inch pots. The bell fruited mallee and fuchsia gum are like large but airy shrubbery that do not get much taller than the eaves.

Posted on by tonytomeo · 6 Comments

Cacti Have Bite Without Bark

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Cacti exhibit unique and striking form.

The most inhospitable spots in the garden that no one wants to put any work into seem to be the domain of cacti, whether or not any cacti actually live there. “Oh, I will just put some cactus there!” is cliché in regard to shadeless and dry spots that get too hot with glare from a south-facing wall. Yet, such spots typically continue to be neglected, and the cactus never get planted.

Why are such distinctive and interesting plants considered to be so lowly that they should be banished to the badlands? Why should they be expected to endure what not other plants are expected to endure? After all, there are so many other distinctive xeric plants, like yuccas, agaves and some aloes, that are just as resilient, and according to some, just as lowly.

Cacti really are not as independent as commonly believed. New plants should actually get watered occasionally until they disperse their roots. If they get watered regularly, they need coarse soil that drains very well. Cactus plants that were grown in sheltered spots really can get scaled if planted where they are too harshly exposed during hot weather.

The main problem with cactus is their nasty spines. Simply planting small plants without getting poked is a challenge. Moving big potted specimens or removing overgrown cactus plants without getting seriously perforated can be daunting. So, even though they might do well in the harsh exposure at the curb, they do not belong in such a high traffic area.

Without foliage or conventional stems, cactus are either awkward to prune, or can not be pruned at all. Barrel cactus have only one or very few round stems. If one of these stems gets to wide, it can not be pruned back. Prickly pear cactus is easier to accommodate only because it has enough stems to spare those that grow out of bounds.

What makes cacti so excellent is their distinctive form. Some have strictly upright stems that resemble those of the organ pipe cactus. Some grow as clumps of short and fat stems. Others grow upward and outward with rounded and flat stems like those of the beaver tail cactus.

Posted on by tonytomeo · 13 Comments

Horridculture – Car Wash

p90116Much of California is chaparral. Much of what is not chaparral is full blown desert. Some coastal climates gets quite a bit of rain; and some climates up in the Sierra Nevada are among the snowiest places in America. Generally though, the most populous and most agriculturally productive parts of California do not get much water to spare.
I certainly do not mean to say that we do not get enough water from rain and snow. We get what the region has always gotten longer than anyone can remember. Those who do not want to live in chaparral or desert need not live in California.
If there seems to be insufficient water for all of us to share, it is merely because there are too many people wanting too much of it, and too many who profit from controlling and selling it to them. Some of us conserve water and landscape accordingly. Others have no problem with vast overly irrigated lawns.
As a horticulturist who grows horticultural commodities, I use what I must for my work. I would prefer others to conserve water in home gardening, but can not complain if they choose not to. If they do not mind paying for excessive consumption of water, that is their prerogative. If rationing becomes necessary, and they do not want to pay fines, their expensive landscapes will be damaged or ruined while mine will survive.
However, it is difficult to not be disgusted with some of the waste I observe in some landscapes. One of the landscape companies that I ‘tried’ to work for years ago regularly watered almost all of their landscapes so excessively that trees succumbed to soil saturation. We then charged significantly to remove the dead or dying trees that we were hired to take care of; hence my ‘Horridculture’ articles on Wednesdays.
We have been getting quite a bit of rain here recently, and are expecting more rain through the next several days. The cloudy blue sky in the background of these pictures was the most blue sky we had seen in quite a while, and it lasted for only a few hours. The lawn in the park here is too swampy to walk on. Just in case there is a slight possibility that there is a small scrap of it that is not sufficiently swampy, it is getting watered generously.
I know mistakes like this happen, and that those who maintain this particular park are seriously overworked and understaffed. I am annoyed about this anyway. With all the modern technology available, why does the irrigation system not know that it is raining so much? If the irrigation system lacks the sort of technology that allows it to monitor the weather, why has no one told it that it is raining so much? If it can not be contacted by telephone, why does no one who know what the irrigation schedule is stop by to disable the system, or just close valves?! Okay, so I know they are understaffed, so I can not complain about it too much.
Nor should I complain about the parking lot getting watered. I know how easy it is for a sprinkler to get knocked out of adjustment. Besides, the windows are rolled up.
However, I am now a bit more concerned about the weather. Too much rain can cause flooding and mudslides. I already know what the forecast is; and now that the car got washed, the rain could get disastrous!p90116+

Posted on by tonytomeo · 23 Comments

When It Rains It Pours

51118thumbFor those who do not remember ancient history, this wet stuff that fell from the sky recently is known as “rain”. It used to be more common, particularly through winter. It has an unfortunate way of getting everything exposed to it quite wet. It makes soil muddy. Yet, rain has many attributes. It is composed of water, so provides much of what irrigation systems have provided for so long in the absence of rain.

Most of us have already been using less water around the garden than in the past. Some plants have suffered, and a some may have died. Surviving lawns are probably not as green as we would like them to be. Just when we think that the garden can not get by with any less, the weather takes over. Even sporadic rain mixed in with mostly sunny weather provides significant moisture.

Not only is more moisture falling from the sky, but the plants and lawns that want it become less demanding through autumn and winter. Evergreen foliage loses less moisture to evapotranspiration (evaporation from foliar surfaces) because it is exposed to less sunlight during shorter days, and because the air is cooler and more humid. Deciduous plants drop their leaves, so do not lose moisture.

Even plants that are sheltered from rain by eaves will need less water because of the cool and humid weather, and shorter days. Some potted evergreen plants that are disproportionately large relative to their pots will likely want to be watered between the rain, only because their roots are so confined. Potted deciduous plants may need their soil moistened if the weather stays dry long enough for the soil to get dry.

Automated irrigation systems need to be adjusted for the changing weather. Some systems may need to be adjusted a few times. By the time the weather gets reliably rainy and cool later in winter, some irrigation systems can be temporarily disabled until the weather gets warmer and drier in spring. Not only does this conserve water; it also makes over-watering and soil saturation less likely.

Posted on by tonytomeo · 18 Comments

Horridculture – Drought

P80905It is a way of life in much of California. Many of us grew up with it, or at least believing in it. Many of us never heard the end of it. That is how it lost its meaning.
Drought is a weather condition. It might last one year or a few. Drought can even continue for several years. For us, it entails less than normal rainfall through winter, only because winter is when rain is supposed to fall here.
As a weather condition, drought is not permanent. There have been a many during the past few centuries of recorded history here, and a few of those have been in just the last half century that I can remember. They happen frequently enough that I can not remember the exact years that were drought years, although I can remember a significant drought in the middle of the 1970s. No drought lasts forever.
If drought lasts forever, or at least as long as anyone can remember, then it is not a weather condition, so is therefore not really a drought. It is ‘climate’.
The climate of much of California is naturally arid. San Jose and the entire Santa Clara Valley have a ‘chaparral’ climate, which is classified as ‘semi-arid’. Some areas near the base of the Santa Cruz Mountains get only about a foot of rainfall annually. Los Angles and the region around it in Southern California have a ‘desert’ climate, which is ‘arid’. Parts of the Mojave Desert get less annual rainfall than other climates get from a single storm.
Although droughts happen here, the limited availability of water is due to the natural climate, not weather. Those who came to California a long time ago knew how to use what was available. The problem now is that there are simply too many people wanting too much of a naturally limited supply of water. Way too many expect way too much.