Chaparral Yucca, Spanish Bayonet – the many named Hesperoyucca whipplei

Despite the cool breeze blowing off the Pacific visible 1300 feet below (400 meters) and four and a half miles away (7 kilometers), it is hot.  Blisteringly so.  The sun beats down on me heating my skin like the bank of coals left over from a bonfire.  Across the valleys the slopes of the Santa Monica mountains waver in my vision as the rising heat warps the air, changing its density and bending the light.  At my feet what looks like heat shadows dance, but upon closer investigation I realize that it is a 6 inch (15cm) layer of extremely fine alkaline dust blowing over the trail like a Martian sandstorm seen from orbit.

This is one of the most diverse areas of California for birds, but all I hear is a single crow cawing as it glides over the ridge and falls into the canyon to the west of me.  Dressed all in black, even the crows must be broiling.  Here and there fence lizards and side blotch lizards scurry abruptly across patches of orangey dust leaving sharp trails in the fine powder that flies up from beneath their feet and whip-lashing tails.

Only the flies and ants are active; green bottle flies, landing to steal a lick of sweat from my arms before I shoe them away and inexhaustible armies of red ants collecting seeds to add to their larders.

It is the middle of the day, the time when the Chumash sun god grows weary of carrying the heavy bark torch he carries across the sky and stoops under its weight, allowing the flame to fall close the the planet’s surface.

Here and there on the drably greenish slopes pillars of bright white stand proud, like blowtorches, clearly visible for great distances in the bright sunlight.

Chaparral Yucca (Hesperoyucca whipplei) 3/4 of a mile away through a 300mm lens, uncropped.

Chaparral Yucca (Hesperoyucca whipplei) 3/4 of a mile away through a 300mm lens (8.5 zoom equivalent), uncropped.

These 9+ foot (3+ meter) beacons are the  inflorescences of an iconic coastal chaparral plant and the reason why I am walking in heat that even the lizards are avoiding.

This plant has a number of common names and has recently been reclassified and renamed in the academic literature.  The most common name is simply “yucca”, with the “y” portion pronounced as in “ya-all” rather than “you”.  This is not to be confused with “yuca” (pronounced with the “you” sound), the cassava root, a common food found through much of the tropics.

This particular species of yucca is also known as Chaparral Yucca, Common Yucca, Foothill Yucca, Our Lord’s Candle, Quixote Yucca, and, perhaps the most telling, Spanish Bayonet.  I find the latter name to be particularity evocative as the long, lance-like leaves are crowned with a needle-like point that easily penetrates clothing, only to break off under your skin, leaving a mark that itches for days to weeks as your body works the barb back out.

Like many organisms, this plant has been classified and reclassified, the scientific name changing back and forth as new information comes to light.  It is currently known as Hesperoyucca whipplei, a name coined in 1892 by Georg Engelmann, but it spent many years happily living under the name Yucca whipplei, when it was thought to be more closely related to Joshua Trees than recent genetic analysis indicates that it is.  Perhaps I am lazy, but I have always referred to it as yucca, and will continue to do so, relying on context to clarify which of several I mean.

The inflorescence of Chaparral Yucca is a mighty affair, that stands high above the landscape in defiance of herbivorous predators, protected by its height and the spiky ball of needle-tipped blades below.

Unopened buds at the opt ad a yucca flower stalk

Flowers and unopened buds at the top of a yucca flower stalk

A senescent yucca with a 4 foot (3+ meter) ball of blades dying after blooming)

A senescent yucca with a 4 or 5 foot (1-2 meter) ball of blades dying after blooming)

For many years these yuccas, which are monocots (having simple leaves with no branch-like structures in them) were though to be in the lily family (Liliaceae) on the basis of their flower construction which closely mirrors the multiple sets of 3  and superior ovaries that are a characteristic of lilies.  Now the yuccas have been moved into the Asparagaceae family which includes asparagus, orchids, hyacinths, Lily-of-the-Valley, and the close relative agave, known to most people in its cooked, fermented, and distilled form, Tequila.

Superior ovaries and the parts in sets of 3 and 6

Superior ovaries and the parts in sets of 3 and 6 – this flower had fallen onto a different plant

When you look at the flowers of a plant you are looking at its genitals, a thought that should give one pause the next time you buy flowers for your partner.  Unlike animals, plants cannot wander about to seek their mates and thus many must rely upon intermediaries for reproduction.  The various colors, shapes, scents, and sizes of flowers are meant to attract very specific sexual intermediaries.  Brightly colored flowers are often attractants for birds, butterflies, and bees that are active during the day, long tube-shaped flowers attract hummingbirds and insects with long tongues, flowers with fetid scents often attract flies and beetles.  The yucca has relatively large bright white flowers with a slightly sweet, nutty smell.

Bright white yucca flowers - white flowers often attract night flying animals such as moths and bats

Bright white yucca flowers – white flowers often attract night flying animals such as moths and bats

These highly scented, bright white flowers, so visible during the day, are meant to attract night flying creatures.  In this case a very specific moth, the California Yucca Moth (Tegeticula maculata).  The relationship between the Yucca Moth and the yucca plant is one of mutual dependence; despite all the other insects that come to steal nectar, only the yucca moth pollinates the plant.  As it does so, it deposits its eggs in the developing seed pods, where the larvae grow, eating some of the seeds as they grow.  These moths only lay eggs in the yucca seed capsules.  In return for pollination (sex) the plant sacrifices some of its seeds.  At this point, neither the plant, nor the moth can survive without the other.  The specificity of the relationship suggest that it is an old one.

The yucca plant is incredibly useful.  The long leaves are tough and full of strong fibers.  The whole leaves were woven into mats and sandals.  The fibers were separated and twisted into extremely strong cord; numerous time I have done this quickly in the field when I need a length of twine and do not want to cut the cord I carry in my pocket.  The flower stalk is full of water and sugar, the flowers themselves are edible, more than edible, they are delicious with a delicate nut-like flavor with a touch of bitterness, a little like cashew blended with bitter almond topped with a dash of gardenia scent.  The unripe seeds are edible raw or roasted, and the dried seeds can be ground into flour.

It is not only humans that find the plants useful and delicious, deer, rats and birds all like to eat the tasty bits, many getting water in addition to nutrients.

Yucca inflorescence being browsed on by a hungry animal

Yucca inflorescence after being browsed on by a hungry animal

It takes a yucca plant 4-6 years to reach flowering stage, then, like a century plant, it dies shortly after flowering.  Even while it is flowering the leaves begin turning color.

Yucca basal rosette with leaves dying after plant flowers

Yucca basal rosette with leaves dying after plant flowers

New plants grow from runners and dispersed seeds.

The old flower stalks can remain standing for another year or two before collapsing, often with the shredded remains of the seed pods still attached.

Fallen flower stalk with empty seed pods attached

Fallen flower stalk with empty seed pods attached

This is one of the iconic plants of the coastal chaparral environment, one which I admire, but treat with the utmost respect, having spent far too much time digging leaf-spikes out of my legs and arms over the years.

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A Brief Stopover in the Santa Monica Mountains

I am back on the West Coast of the US for a few weeks before I fly off into tomorrow sometime in November.  The specific part of the west coast I am in is the Santa Monica Mountains, a rugged stretch of steep sided hills perched over the Pacific Ocean covered with blanket of dense chaparral.

Evening sunbeams in Topanga

The precipitous, heavily weathered mountain slopes are eroding from ancient sea-floor uplifted and broken by geologic stresses, frequently manifesting in the form of earthquakes.  The region is dry, though fog is common and periodic rainstorms can quickly drench the area, causing local flooding and landslides.  The dusty ground is colored a dull orange/tan with angular, flat, broken pebbles peeling out of shallow, soft bedrock with occasional anemonite and bivalve fossils.  Under the twelve foot chaparral canopy the gritty soil is overlain by several inches of slowly decomposing leaf-litter and twigs, loose in some places, held together by dense mycelial mats in other places, particularly under the scrub and live oaks.

Infrequent damp, cool places are home to massive coastal live oak (Quercus agrifolia) and California sycamore (Platanus racemosa) while a bewildering variety of woody shrubs make up the body of the chaparral cloaking the rest of the mountains.  Here and there small meadows, potreros in the southern California vernacular, and wind-blasted rock outcrops break up the gray/green vegetation.

Lemonade Berry (Rhus integrifolia) flower buds

Chamise, Toyon, Scrub Oak, Lemonade Berry, Ceanothus, Yucca, and various sages make up much of the more common large shrubs with Black Walnut, Elderberry, Coastal Live Oak, and California Sycamore making up the primary larger trees.  The softer vegetative plants of the understory tend be short-lived, only appearing to bloom and set seed after the rain.

The thick, leathery leaves of the Lemonade Berry (Rhus integrifolia) in the image above are fairly typical of chaparral plants in that they are mostly evergreen and have evolved to husband moisture.  Some plants steal their nutrients from other plants, Dodder (Cuscuta californica) is common in the chaparral, some years blanketing their hosts with yellow-orange leafless vines sporting nearly invisible flowers.

Dodder (Cuscuta californica) on Lemonade Berry. Dodder is most active after rains.

For such a dry region the diversity of both plant and animal life is astounding.  The most obvious animal life during the day are the birds.  Birds of all sizes everywhere, year round.  Little tiny acrobatic birds such as the Bushtit traveling in small noisy flocks.

Bushtit (Psaltriparus minimus) on scrub oak

Large birds of prey soaring overhead in search of thermals or their next meal.

Red-Tailed Hawk (Buteo jamaicensis) riding the wind

Meadowlarks, finches, wrens, thrashers, scrub jays, woodpeckers, hummingbirds quail, and a host of other birds flit about within earshot, if not within eyesight.

Western Meadowlark (Sturnella neglecta) atop a Toyon (Heteromeles arbutifolia) shrub, a popular food bush for many birds. Toyon is also known as Hollywood, the plant Hollywood owes its name to.

Anna’s Hummingbird (Calypte anna) perched on a non-native Tobacco Tree (Nicotiana glauca)

Mammals abound as well.  Small rabbits scatter like frogs in a pond in the evenings, and in the mornings I find fresh coyote, fox, bobcat, skunk, raccoon, deer, and mountain lion tracks on the unused dirt roads.  In the potreros badgers are not uncommon, large woodrat piles abound, bats fly through the canyons in the evening, and ground squirrels are everywhere.  Sometimes, if you have a quiet foot, a lot of patience, and good deal of luck you sneak up on these animals.  A few years back I was out here and found a coyote sleeping in the sunlight.

Coyote (canis latrans) sleeping in the sunlight

This being a dry area there are numerous lizards and snakes, mostly hidden from sight, and insects of all sorts.

I prefer wet places, places that stay green, but I do appreciate and enjoy the diversity of life here in the steep chaparral.  It is strange to be here between damp New England and my next home in Borneo where I will receive 3-4 meters of rain a year.

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Some of these photos are taken with a Nikon D80, some with a Nikon D90, and several with a Nikon D600.  I am still learning the latter camera, but if any of you out there are debating buying the D600, I can honestly say I recommend it.  The Meadowlark and Hummingbird images were taken with the D600 and are cropped from much larger images.