Wildflowers in the shade

The redwoods rise all around us, rough-textured towers. We walk in their thick shade. Just off the path, a curl of purple catches my eye. We step closer and see an orchid, a single bloom on a slim stalk, with just one leaf hugging the ground. Looking closer, we see intricate white and yellow patterns on its large lower petal. Then we notice a little trail of the same flowers under the trees, about eight or ten all together.

The western fairy-slipper lives in shady forests and bogs. Its bright color and sweet smell attracts pollinators—especially newly hatched queen bumblebees who don't realize that it offers no nectar.

Spring is wildflower season. The showiest blooms, called superblooms, happen in sunny grasslands where poppies, lupines and others paint whole hillsides, especially if the rains have been good. These are most dramatic in Central and Southern California where it is drier. In Northern California, there is enough rain that introduced European grasses take over many grasslands, leaving less room for native wildflowers. This spring, I have been appreciating a less dramatic class of wildflowers: those that bloom in deep shade in the forest, such as the western fairy-slipper.

In the superbloom grasslands, the limiting factor is water. In dry years, the blooms are much less dramatic, and the flowers disappear as the spring dries out and heats up on its way to summer. In the shade of forests, the limiting factor for flowers is often light. Only flowering plants that are adapted to photosynthesize in low-light conditions survive, and they tend not to grow in carpets but in small patches where light makes it to the forest floor.

Look carefully in the shady woods and you might see the white petals of a pacific trillium unfurled in the center of three wide leaves, or the giant wakerobin, a trillium with a larger, dark-magenta flower.

The seeds of trilliums are dispersed by ants. Ants take the seeds in order to eat the elaiosomes—little blobs of protein and fat—that grow attached to the seeds. Trilliums grow in wet shady areas, often near streams. Another wildflower found in similar habitat are largeflower fairybells, elegant white bells that hang in small bunches.

The checker lily (or chocolate lily) is a wildflower of the shade that is found in drier forests, such as oak forests in the Napa hills. Looking from above, you might not even notice the flowers, since the outside of the petals are so muted. Inside, they have brighter yellow and brick red.

Some sights in nature are thrilling because they are spectacular. Others are thrilling because they are subtle and hidden. When you find them, you feel you've uncovered a secret, a treasure you could have walked right past.

LINKS:
California Native Plant Society
Salt Point State Park (where I saw the western fairy-slipper and pacific trillium)
Steep Ravine Trail (where I saw the giant wakerobin and largeflower fairybells)

Vernal Pools at Vasco Caves

We eat our lunch on a sandstone outcropping. A pair of orange-crowned warblers appears and disappears in the bushes. A rock wren chirrs behind us. Then the ranger gathers the group and leads us to where pools, ranging from the size of a sink to a large hot tub, dot the rock.

We bend over the murky water of a pool. Mysterious small shapes move. Some resolve into black tadpoles (sierra chorus frogs), others into water boatmen (small bugs that look like rowboats with pairs of oars). Then we spot one of the creatures we've come to look for: the nymph of a California tiger salamander. The tiger salamander is poorly named- the adult is black with bright yellow spots. The nymph is semi-translucent, dappled green and brown, tadpole-shaped, with an extravagant fringe of gills.

We are also looking for vernal pool fairy shrimp; at first we see none, but later I spot one scrumping along the edge of an algae mat in one of the smallest pools. It is about a centimeter-long, gray, with a row of rippling legs. Eventually, the group finds many more fairy shrimp.

These pools fill with the winter rains, and last only a few months. Here on the east side of the coast range, spring turns hot and dry quickly most years. Fairy shrimp hatch from cysts when they are in cool water. The shrimp eat algae, mate, lay new cysts and die before the pools warm up. A fairy shrimp cyst is incredibly tough: it can survive years of drought. A cyst may hatch one year after it is laid or decades later. Tiger salamanders also use the pools to reproduce. Adults spend the dry season estivating in ground squirrel burrows, then migrate up to the pools during the wet season. They lay eggs, which hatch and become the nymphs we saw. The salamanders and their nymphs eat fairy shrimp. The shrimp thrive in pools that are hard for many salamanders to reach.

The pools, and these rare shrimp and salamanders, are protected in Vasco Caves Regional Preserve. You can only visit the park on a guided tour, a measure to protect these species, and also to protect the sacred Native sites in the park. The sandstone outcroppings and the shallow caves scooped from their sides have been sacred to the local Muwekma Ohlone, Bay Miwok, Chochenyo, and Delta Yokuts* people for hundreds and probably thousands of years. There are petroglyphs made in ceremonies in several of the caves. As we entered the park, we saw a pair of prairie falcons fly from a cliff to the top of an oak. Later, the ranger showed us a petroglyph that likely shows Wek-Wek (prairie falcon) and the myth of his death. Up until people were created, death lasted only four days. Coyote decided that with the arrival of people, death would need to become permanent to avoid overcrowding. We-Wek's was the first permanent death.

We step from one vernal pool to another, peering to glimpse the teeming, tiny lives. Bright yellow flowers and vibrant green leaves carpet the low areas between the pools. In a few weeks, the rains will stop and the pools will dry out. The tiger salamander nymphs will have grown to their black and yellow glory, and buried themselves underground.  The only fairy shrimp will be potential shrimp in time-capsule cysts. The top of the sandstone will be sun-blasted and bare.

Each individual's death is permanent. Our time in the pool is brilliant green and brief. New lives begin with the cool rains.

LINKS
Vasco Caves Regional Preserve
Muwekma Ohlone Tribe
California tiger salamander information from the Pacific Forest Trust
Vernal pool fairy shrimp information from Sacramento Splash
Prairie falcon information from the Cornell Lab of Ornithology

*These names may describe overlapping cultures and/or more than one of these names may describe the same group. This list is likely not exhaustive.

Tide Pools: Holes and the Hidden

The wind pours into our faces. We walk the short path from the parking lot at Gerstle Cove in Salt Point State Park toward the shore. We're walking past low bushes and a few purple blooms of Douglas iris. From up on the path, it doesn't look like a particularly low tide. At a gradually sloping beach, low tides are obvious—the beach stretches way out— but at a steep shore like this one it's harder to tell. We clamber down the honeycombed sandstone toward the churning waves. Now the low tide we've stumbled upon (one of the lowest of the month) becomes obvious.

There are crimson bat stars and rock walls textured in gooseneck barnacles. Shag carpets of sunburst anemones wave teal and pink tentacles.

Peering and picking our way, we discover abalone and red sea urchins—dwellers of the lower section of the intertidal zone that are only revealed by quite low tides. We even come upon a gumboot chiton, a wrinkled red burl the size of a small loaf of bread. I've only seen one once before in years of tide pooling.

A gumboot chiton lives low on rocky shores, crawling very slowly, scraping off algae with its radula (an organ like a tongue). Its radula is covered in tiny teeth tipped with magnetite. Magnetic teeth!

We see huddles of pacific purple sea urchins, each tucked into its own perfectly-sized hole in the sandstone. Did they somehow carve these homes or did they just find these spots and move in? We had seen somewhat similar holes in the sandstone much higher on the shore where no urchin could live, but these holes seem so perfectly matched to their residents.

Later, I read about a study by Michael Russell at Villanova University in which he and his team documented pacific purple sea urchins eating holes into mudstone, sandstone, and even granite. Apparently, the five teeth that a sea urchin uses to eat kelp are also used to break off and eat bits of rock. In one year, the urchins in the study ate an average of 63 cubic centimeters of sandstone each. Eating a hole into rock provides an urchin with a safer home.

These wonders we saw are almost always covered by water. We only got to see them because we caught the cycle of the tide as it pulled back the water to nearly the farthest reach, revealing what is always there but almost always hidden. There are other moments in natural cycles like this. In the fall, the yearly cycle of temperature causes leaves of deciduous trees to lose their chlorophyl. When this green pigment is pulled away, it reveals the orange, red, and yellow colors that were there in the leaves all along, but hidden by the green. Each night the light of the Sun is pulled away, revealing the stars. The stars are there in the daytime too but sunlight hides them from our view. Two days ago, I walked in snowy winter woods in Michigan. I saw several bird nests in the bare branches of the trees, holding snow rather than eggs. These nests were built in spring, but would have been invisible then, hidden by leaves.

Salt Point State Park
Tide Tables
Information about Gumboot Chitons from the Monterey Aquarium
New Scientist Article About Rock-eating Urchins

Winter "Wildflowers": Mushroom Blooms

I see a stand of live oak. Their long limbs curve over the leaf litter, wet bark arcing black like calligraphy. I park the car and walk under their canopy. My feet crunch through the wet leaves. There! Bright red peeks out at me, circles of brilliant color among the winter browns of fallen leaves.

In winter, mushrooms pop up through our forests and fields in northern California. There are redhead russulas— the ones I spotted under the oaks— dark purple amethyst laccaria, lilac blewits, yellow and red witch's hats, rusty orange jack o'lantern mushrooms, silvery blue-black midnight entolomas, glistening green parrot mushrooms, and hundreds and hundreds of other species (not all so colorful).

Besides the fact that many are colorful, mushrooms are like wildflowers in another way: they are the reproductive parts of a larger organism. Most of an individual fungus is made up of mycelia, a web of underground tendrils. When conditions are right (generally meaning the right amount of moisture, though some mushrooms are temperature dependent instead) the underground fungus send up a fruiting body: a mushroom. The mushroom releases spores that act like seeds, spreading to possibly become new individual organisms.

A colorful wildflower is colorful in order to attract a pollinator-- a bee, a butterfly, a hummingbird. Most wildflowers bloom in the spring when temperatures are warm enough for these pollinators to be active but there is still plenty of moisture. Fungi don't depend on pollinators. When they produce mushrooms and spores, they have already engaged in sexual gene swapping underground, or their reproduction may be asexual without combining genes from different individuals. Since they don't need warm temperatures for pollinators, many mushrooms bloom at the height of our wet season when spores are most likely to land in welcoming wet soil.

But why are mushrooms colorful, if they don't need to attract a pollinator? Some mushrooms may benefit from using bright color to attract animals to eat them: if an animal lifts a mushroom or breaks it apart, that gives the spores a better chance of spreading far to a new suitable location. Some mushrooms are eaten by flies which disperse the spores when they poop them out later. On the other hand, some mushrooms have powerful toxins that can harm or even kill any animal (or mushroom hunting human) that eats them. This may be to keep animals from eating the mushrooms before the spores have fully developed, but no one really knows.

Mushroom blooms are a beautiful and mysterious part of our winters. Fungus are some of the least-well-understood organisms in our ecosystems. Their evolution and their relationships with other species in our ecosystems are full of unsolved mysteries. Even the identifying of species is an ongoing puzzle. A few weeks ago, I came across mushrooms that I think were Cortinarius ohlone-- a species only described about 10 years ago. And there are new species of fungi discovered in California every year.

MykoWeb: California fungi website

Mushrooms of the Redwood Coast: the best field guide for our area

Tilden Regional Park: lots of mushroom habitat

Redwood Regional Park: more mushroom habitat

Slime mold networks

As I passed through a eucalyptus grove on campus, something brilliant yellow caught my eye. I bent closer. A gloopy, ruffled smear of yellow covered a curl of eucalyptus bark. Tendrils crept out from one end. A slime mold? I took a picture and uploaded it to iNaturalist when I got home.

iNaturalist is a website or app in which you can upload photographs of living things, tag their location, and add your guess of an identification. The site's artificial intelligence suggests possible species to help you with your identifications. Once you put up a picture, other people can confirm your i.d. or suggest an alternative. The site suggested dog vomit slime mold-- Fuligo septica-- for my picture. I don't know much about slime molds but that sounded like a good description of what I'd seen!

The next day, Sarah Lloyd, a slime mold expert from Tasmania, Australia had left a comment on my post: "It's the plasmodial stage of a slime mould that's still transforming. Can you return and get a photo of mature fruiting bodies?I don't think it's Fuligo. It's more likely to be Leocarpus fragilis; the substrate looks right and the species seems to be extremely common at the moment in California." I went back to the same spot two days later, and there was nothing yellow to be seen. I started poking around, and found tiny brick-red bulbs coating the eucalyptus bark on the ground.

It was indeed Leocarpus fragilis! This slime mold, like others in its class, spends much of its life as a tiny single-celled organism. But after rain, it is able to find much more of the bacteria and fungi it eats, and the cell begins to expand dramatically. That blob of yellow slime I saw was one single enormous cell! The cell send out thin tendrils searching for nutrients. A slime mold in this phase grows into a web or network, passing nutrients through its pathways, growing thicker where conditions are good. Researchers have found that slime molds can solve mazes and generate efficient solutions to problems of how to connect a set of dispersed resources. Slime mold networks can take a range of forms.

Eventually, the slime mold transforms again, forming fruiting bodies where spores grow. These spores are eventually dispersed and start the life cycle anew as individual slime molds.

There's an interesting parallel I think, between the lives of slime molds and our new human way of living with the internet. Slime molds build networks and webs, finding and passing nutrients. We form virtual networks and webs, finding and passing knowledge, lies, jokes, art, crap, and memes. This web connected my photo of a yellow smear to a naturalist in Australia who knew what it was, and sent me back to see a miraculous transformation.

iNaturalist

Sara Lloyd's website

Article about Sara Lloyd from iNaturalist NEW!

Intro to slime molds from the University of California Museum of Paleontology at Berkeley

Slime mold intelligence from Nature

Newts on the move

We're under the oaks. Drips from last night's rain are filtering down from the canopy, soaking into the leaf litter. The forest floor is a mosaic of browns, oranges, and greens—oak leaves, bay leaves, acorns, lichen-covered sticks, patches of mud. We're looking for a particular orange—the creamy light-orange of chanterelles. They are late to come up this year. The series of weak storm systems we've had makes the forest floor look wet enough, but it seems we haven't had quite the necessary soaking yet. Something catches my eye, a darker, rusty orange. And it's moving. A rough-skinned newt deliberately lifts one front leg, and the back leg on the opposite side. It negotiates over a stick. I see a flash of bright orange as its belly shows. I hunker down. I watch the newt slowly make its way downhill.

Each winter, rough-skinned newts (and their close relatives, California newts) migrate to ponds and pools to reproduce. Scientists aren't exactly sure how the newts navigate, but it seems they use a combination of smells, sights, and following slopes downhill.  A newt can travel about half a mile in five days. Walking to my mushroom spot, I cross a small muddy stream that only appears in the winter. Perhaps the newt I saw was headed to a pool in this stream.

The newt's bright orange belly is a signal to possible predators of the powerful toxin in the newt. A single rough-skinned newt has enough toxin to kill several adult humans. This trait developed through co-evolution with the garter snake, the rough-skinned newt's only predator. As rough skinned newts evolved ever stronger levels of toxin, garter snakes developed ever greater capacity to withstand the toxin.

A somewhat more distant relative, also found in our area is the California slender salamander. I find these by looking under rotting logs. You might at first mistake this salamander for a worm. Then you notice the bug-eyed old man face, and the limbs, thin as angel hair pasta. These salamanders also have a seasonal rhythm. In the dry months they burrow under ground and become dormant. With enough rain they emerge, searching for insects in underground tunnels, below rotting logs, and in the leaf litter. While the rough skinned and California newts undertake epic (for their size and speed) journeys, a California slender salamander stays put. Most individuals never leave an area of about two meters.

Ensatina is another local species that lives its life in a small area. These can also be found under rotting logs.

Newts and salamanders highlight for me the different scales of our shared world. It takes a newt days to clamber down to its breeding pool—the longest walk of its life. I walk the distance in minutes. My home in the flats is like a distant galaxy for the newt. The newt experiences details of the forest floor that I pass right over: the contours that lead rainwater to filter down to a muddy pool, the routes over or under a fallen log. And what details and intricacies a slender salamander must know of its two-meter world!

(We did eventually find the first few chanterelles of the season!)

More information about newts and salamanders from Amphibiaweb:

• Rough-skinned newt
• California newt
• California slender salamander
• Ensatina

Places to see newts and salamanders:

• UC Berkeley Botanical Garden (The pond in the Japanese garden is a great place to see mating newts)
• Tilden Park (They close South Park Road for the season to keep migrating newts safe!)

A swirl of wild geese

First you hear them: a rippling, overlapping chatter. Then you see that the field is covered in geese: dark gray geese in front, a sea of white birds behind. A wave of wings lifts up from the mass and blurs the sky above. The wave spreads as more birds take off. The white geese reveal striking black on their wings.

There are so many of them. It baffles the eyes. It sends a startle of delight to your chest.

Every winter, thousands of snow geese, Ross's geese, cackling geese, and white fronted geese migrate south from their nesting grounds in Canada and Alaska. Huge flocks spend the winter in the Central Valley, including at the San Joaquin River National Wildlife Reserve where my parents and I saw them from the Beckwith viewing platform just before New Year.

The dark gray geese we saw were cackling geese. Cackling geese look almost exactly like Canada geese but smaller, and until recently the various populations were considered subspecies of Canada goose. Those we saw were Aleutian cackling geese, the subspecies of cackling goose that nests in the Aleutian Islands, the arc of volcanic islands trailing off to the southwest of mainland Alaska. They travelled over 2,000 miles from their nesting grounds to this muddy field near the San Joaquin River.  Through binoculars, I spotted a few bright orange goose feet. These belonged to greater white-fronted geese, just a few of them tucked in among the masses of cackling geese. The white geese behind were snow geese and Ross's geese, two species that are nearly identical: almost all white when on the ground, with just a touch of black near the rear, bold black on the wings in flight. The snow goose has a larger bill than the Ross's and some have a slight yellow tinge on the head and neck.

Our understanding of species has changed based on genetic evidence, and continues to change as scientists gather and analyze more of this data. Genetic evidence revealed that cackling geese are not just smaller Canada geese, but rather their own species. Cackling geese look so similar to Canada geese (and Ross's geese look so similar to snow geese) because their evolution into separate species is relatively recent. There is still some interbreeding among the species and subspecies where they overlap. Changes in land use, hunting, conservation and climate over the last several centuries has altered the ranges of these goose species and likely affected the ongoing subtle evolution of the shifting populations.

Watching the flocks of geese fly through the chill December air, the groupings  form, shift, and reform. Threats or disturbances I can't see send swaths of bird into the air. Something sends them slanting toward the river, while another group settles to the ground. The complex patterns mirror the changes and shifts in their populations on a much larger time scale.

Cornell Lab of Ornithology:
Cackling goose
Canada goose
Snow goose
Ross's goose
Greater white-fronted goose

San Joaquin River National Wildlife Refuge