Plants that aren’t green

finding other sources of metabolites

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Most of us think of plants as being green, at least in summer. The green comes from the pigment chlorophyll, which uses sunlight to knit carbon dioxide and water together, forming carbohydrates that the plant can metabolize. Lucky for us, oxygen is a by-product of the process. There are a few local plants, however, that don’t have chlorophyll, or at least very little, so they don’t do photosynthesis and have to obtain their energy elsewhere. Here are examples:

Northern ground cone. This interesting Beringian plant goes by the reverberating scientific name of Boschniakia rossica, named for a Russian botanist Boschniak and presumably someone named Ross. Such names reflect nothing about the plant itself, obviously, and only show who knew whom. That’s a shame, because this plant is rather weird and wonderful.

Northern ground cone got its common name because, to some people, the above-ground plant resembles a pine cone. It is common in certain places around here, mostly where there are alder trees. Lacking chlorophyll, it cannot synthesize carbohydrates for itself. Northern ground cone is entirely parasitic, getting its nutrition from other living plants, especially alders but also other species.

The brownish spike that emerges from the ground in summer is the inflorescence, bearing numerous small flowers. When mature, the spike produces huge numbers of tiny seeds.

The plant is reputed to have some medicinal value for humans (although, like many plant medicines, it has some toxic properties too), but part of my interest in it stems from observing that it seems to be a favored food item for bears. In the Dredge Lake area, for example, I often see wide swaths of ‘rototilling’, showing where bears have been foraging for northern ground cone. Bears seek out the underground base of the spike and generally leave behind the spike itself. The stem-bases are not notably rich in basic nutrients such as nitrogen, phosphorous, potassium, or calcium, and probably provide carbohydrates. When bears have been eating lots of ground cone, their scats look (to me) rather like mushy cracked-wheat porridge.

fly-entering-groundcone-flower-by-bob-armstrong
A fly enters the flower of a northern groundcone. Photo by Bob Armstrong

The tiny flowers are accessible to small insects, which are sometimes seen to visit, but it is apparently not known if they are pollinators. A different species of ground cone is reported to be self-pollinating, and a little fly sometimes attacks the flowers of that species. But the story for northern ground cone is yet to be discovered.

Pinesap. This is another strange plant that lacks chlorophyll. Pinesap (alternatively, Dutchman’s pipe) grows under conifer trees. It seems to be much rarer than ground cone in our area, as I have almost never seen it around here. It is sometimes said to be saprophytic, obtaining nutrients from decaying vegetation, but the reality is more complex. This plant and its close relatives are obligately dependent on mycorrhizal fungi whose underground filaments connect to the roots of nearby trees. The fungi draw nutrients from the host trees and delivery them to the pine sap plants. Thus, the pine saps are indirectly parasitic. Pine saps have yellowish or reddish stems, with yellowish or red-tinged flowers usually bent over to one side. When the fruits mature, however, they are upright on the stem. Bumblebees are reported to be the most important pollinators.

Certain local orchids are also saprophytic. We have two species of coral-root orchids, both of which are said to be saprophytic, but again the arrangement may be more complicated. In addition to needing mycorrhizal fungi for seed germination, these plants may, like the pine sap, actually obtain nutrition via their associated fungi that drain nutrients from nearby host plants. In addition, one coralroot orchid is said to have small amounts of chlorophyll and thus synthesize some of its own carbohydrates. Coralroots may be pollinated by small flies, such as dance flies, but probably also have the capacity for self-pollination.

Prowling the intertidal

variety and mystery in a challenging habitat

I find it great fun to go out on a minus tide and prowl along the exposed intertidal zone. It’s a bit like a treasure hunt—seeing how many different kinds of invertebrates and little fishes I can find. Being a terrestrial ecologist, I often can’t put specific names on what I see, but the variety of colors and body form is always intriguing.

Many of the critters like to hide under rocks, so I have to turn over those rocks—very carefully, so as not to crush the animals. When I’m done inspecting what’s been exposed, I try to put each rock back exactly as it was, again without crushing anybody, to preserve them and their hiding places. On a recent low tide, I was dismayed to see that other searchers had often not replaced the turned rocks, leaving the various animals exposed to hot sun and predators.

Seeing all those intertidal invertebrates made me think about the many ways they have for eating, many of which have no counterparts among the vertebrates. Most vertebrates have jaws, sometimes with teeth; only a few lack jaws altogether (lampreys and hagfish). It’s very different, among the invertebrates.

In the intertidal zone, stand in one spot and contemplate the several styles of feeding used by the array of invertebrates there. Sea cucumbers filter small particles from the water using tentacles; barnacles do so with their legs. Sea stars evert their stomachs, either wrapping a prey item or inserting the stomach into a clam shell to digest the meat. Crabs mince and nibble their prey to bits, using pairs of sharp mouthparts. Snails of many sorts rasp their food with a file-like structure: predatory snails rasp a hole in the shells of mussels or clams or other snails, shredding the meaty contents, while the herbivorous ones graze by scraping algae off rocks and seaweeds. Ribbon worms, pile worms, and iridescent worms have a bulbous proboscis that can be extruded; armed with sharp hooks or daggers, the proboscis clamps onto the prey and pulls it back into the mouth of the predator. Detritus feeders, such as lugworms, vacuum up soft junk from the substrate. And that’s just a sample.

We often find several kinds of sea cucumbers, sea stars, snails, chitons, anemones, and so on, each time we go cruising the low tide line. Occasionally, we find something unusual or uncommon, such as the nudibranch (a shell-less mollusc) that eats barnacles. Recently, we found numerous odd lozenges of a jelly-like substance strewn over the sands; each little oval was about an inch long and contained rows of tiny eggs or embryos.

This was a big mystery for us, so I sent a photograph to a friendly local expert on marine invertebrates, who said that these were the cocoons of the Pacific lugworm. Lugworms can live at quite high densities in the sediment, each one in a J-shaped burrow. They feed on detritus from the surface of the sediments; in the process, they take in a quantity of dirt as well, which is eliminated in long thin coils (which observers often see on the surface). We happened to be on the beach during the reproductive season, and females had produced these cocoons of babies, each one attached by a thin string to the mother’s burrow. According to research reports, males produce packets of sperm, which get washed over the surface of the sands to a female’s burrow, where the packets break open, releasing the sperm to fertilize the female’s eggs. The eggs are brooded in cocoons by the female either in her burrow or, in the present case, tethered to her burrow. When the young emerge from the cocoon, they are little wormlets that forage over the sediments near the surface.

I’m looking forward to our next ‘treasure hunt’!

Purple mountain saxifrage

a hardy flower and a spring delight

One of the earliest flowers to appear in spring is purple mountain saxifrage. In April some of us make a point of regularly checking certain places where we know it lives, just for the pleasure of watching for the first open flower and then the appearance of more and more blossoms, until there are multiple patches of the pinkish-purple flowers on some of the local rocky outcrops.

purple-mountain-saxifrage-on-April-10-2013-at-Nugget-Falls
Photo by Bob Armstrong

This low-growing plant occurs in Arctic regions around the world, and in alpine areas of central Asia, Europe, and North America. It’s a tough little plant, quite resistant to drought and water-stress. It forms associations with mycorrhizal fungi that provide nutrients and water, in exchange for carbohydrates produced by the saxifrage leaves. As with several other early-season bloomers, the flower buds are actually formed the year before the flower opens, but eggs (in the ovary) and sperm (in pollen) don’t develop until spring.

Female parts of the flower mature before the male parts do, which reduces the chance of self-pollination (pollen fertilizing future seeds in the same flower). Most seeds are produced by out-crossing (pollen fertilizing future seeds on a different plant).

The flowers are pollinated by insects of various sorts, including bees and flies. Early in May, we watched a female margined-white butterfly visiting one flower after another, so presumably there are minute amounts of nectar therein. These insects don’t see the longer (reddish) wavelengths, so they see the flowers as bluish. However, studies have shown that seed production is often limited by low levels of pollinator activity, perhaps in part because bad spring weather sometimes reduces insect activity. In addition, one study showed that as soon as other flowers started to bloom, insect visitation to the saxifrage decreased, as the insects found preferred sources of food.

This is an ecologically variable species, with different types adapted to different conditions of soil, snow-melt, length of growing season, and so on. For example, one study showed that the plants growing in cold, wet soils with late snow-melt had higher metabolic rates and faster production of shoots than those in warmer, drier sites, but they did less well at storing carbohydrates or water for hard times. In some areas, there are two growth forms that grow side by side but differ in structure (prostrate vs cushion-like) and in reproduction: one does better at seed production but the other excels at propagating by shoot fragmentation.

On the Old World Arctic tundra, purple mountain saxifrage flowers and old seed heads are eaten by barnacle geese when they arrive on the nesting grounds, and reindeer eat it too. I have not found information on animals that consume this plant in North America.

A word of caution: If you see this pretty plant in the wild, please do not remove it! That deprives lots of other folks of the pleasure of finding and seeing it in its natural setting.

Ralston Island

observations by amphibious naturalists

We left our camp on Lincoln Island in sunshine, with a following breeze. Arriving quickly at the wide beach on Ralston, we set out to explore the island. The trail marked on old topo maps proved hard to find, but a maze of deer trails made it easy to move around the forest. We wandered toward the north end of the island.

All along the way, I enjoyed the numerous flowering orchids. All had tiny, intricate flowers, rather than the showy ones that most folks notice. There were twayblades, named for the paired leaves on the stem. Darwin, long ago, figured out just how the little twayblade flowers contrive to be pollinated by visiting insects: when an insect touches a certain part of the flower, a sticky drop explodes outward, carrying pollen and sticking it to the insect, which carries it to another flower.

The most common orchid was one known as one-leaved malaxis or white adder’s tongue. A single leaf sits at the base of the flowering stem. There are no adders involved here except in somebody’s over-active imagination! We also noticed several rattlesnake plantains, which are not plantains at all. Nor do they have anything to do with rattlers, except that someone decided that the patterns on the leaves looked like snakeskin.

The most colorful ones were the pink coralroot orchids, which lack green pigment and so cannot synthesize their own carbohydrates. They are variously reported to be saprophytic (feeding on decaying organic material) or indirectly parasitic on other living plants by means of fungal connections. Ralston hosted some spectacular stands of this orchid.

As we strolled around, we saw no signs of red squirrels or porcupines, which presumably would have a hard time getting out there. Juvenile ravens were loudly making known their wants, as they tried to follow their harried parents through the trees. Songbirds still sang, even in late June; I heard song sparrow, hermit thrush, ruby-crowned kinglet; one hermit scolded us severely, using notes I’d not heard before, so we must have been too close to a nest or chick. A strange-looking woodpecker moved through the canopy; after checking the books, I guessed it was a hairy woodpecker—which are darker here on the coast than they are elsewhere.

The north end of the island was productive. There’s the densest, tallest stand of crabapples I’ve ever seen, and some of the gnarliest hemlocks. As we pushed through the brush toward a boulder shore, we stumbled into a small meadow, perched on a headland and sporting a surprising and lovely stand of wild iris. Out among the boulders we finally spotted some oystercatchers displaying to each other, apparently amicably. Later, we saw an oystercatcher vigorously and loudly chasing an eagle, which presumably had had designs on an oystercatcher chick.

Then it was time to head back to camp. Ah, but by now the tide had turned, not in our favor, and the headwind had risen noticeably. It seemed do-able, however, so off we went. Around the first point, things became more difficult: a stiffer breeze, a stronger tidal current, and there were also frequent, strong gusts of wind. We had to paddle hard and constantly, just to keep from going backward! In between those gusts, slow forward progress was possible, but it still took about four hours of nonstop hard paddling to get back to camp. Ooooofff!

Rambling in winter

owl wings, wolf tracks, otter sign, and ice formations

The short December days don’t allow for long explorations, but even short ones can be productive for a curious naturalist.

I took a little stroll on the wetlands on the north side of the Mendenhall River. At least four short-eared owls were coursing low over the grassy meadows, with their distinctive slow wingbeats. They were looking for voles, their favorite prey. Vole tunnels were evident under the thin and patchy snow, but I did not witness a capture, despite some serious watching. Short-eared owls often forage during the daylight hours, probably using visual clues to supplement acoustic ones. Like other owls, they have the ability of pinpoint a prey animal by using only their ears, but in daylight, their eyes are useful too.

short-eared-owl-by-Jack-Helle
Photo by Jack Helle

Plodding on snowshoes around some mid-elevation meadows, we noted lots of deer tracks, some not-recent porcupine trails, and several sets of hare and squirrel tracks. But the big excitement, in two widely separated sets of mid-elevation meadows on two different days, was finding clear, recent footprints of wolves; they wove in and out among the trees at the edges of the meadows. That was a high point of the rambles on those days!

A friend and I walked out toward Crow Point and the Boy Scout beach, but we soon forsook the trail for explorations right along the river. There was not a lot of bird activity—a little squad of Barrow’s goldeneyes and a few gulls, but on a little grassy rise above the sandy river-shore we did find something interesting. In the snow that covered some of the grass, we saw otter tracks leading up to the top of the rise. There we found three or four spots where the grass was torn up and heaped off to the side. What were the otters doing? Just playing? Scent marking (the grassy heaps smelled faintly sweet)?

Where the trail reaches the beach, recent heavy erosion had chopped off a good part of the dense stand of little spruces and carved a steep cliff in the sandy edge of the grassy bank. The most severe erosion was very localized. Just around the corner, where the beach extends southward, erosion was much less. We wondered if there had been a big northerly wind that coincided with a good high tide. Possibly the bank around the corner was somewhat protected from wind and wave by the broad, sandy flats that extend away from shore and are exposed at low tide.

We walked south on the beach, watching gulls at the water’s edge picking up and carrying black lumps that were probably little clumps of mussels. The gulls did not do much else with those lumps, at least while we were watching. Gulls tracks were everywhere. In the dry sand at the top of the beach were many tracks of another kind of bird—something small, smaller than a robin. But not a shorebird, because this bird had a well-developed hind toe, which shorebirds lack. The unusual thing about these small birds was the gait—lots of running, with intermittent hopping. Most of our small birds, such as sparrows, seldom run; they usually hop. So what bird could this be? I think the two most likely candidates are pipits and horned larks, but December is rather late for them to stay here.

Another stroll, just after a few days of freezing temperatures, yielded some of the most beautiful ice formations we’d ever seen. Dead twigs and fallen logs had absorbed water from fall rains; as the low temperatures froze the water, it expanded. The expanding ice was extruded from the wood in thin sheets of fine, almost silk-like strands. The most elegant sheets were up to five inches long, curving gracefully like a tousled head of wavy hair. Alas, no camera!

Rambling

a stranded coho, foraging dippers and a gang of orcas

There’s little I like better than rambling around the woods, meadows, and beaches, just seeing what’s to be seen. Sharing these little explorations with a like-minded friend is the best, but solo jaunts are good too. There is always something of some interest. Although November is one of the hardest times of year for curiosity-driven rambling, here are a few observations.

We walked the west-side beach of Mendenhall Lake toward the glacier, planning to return on the West Glacier Trail. The water level is low in the lake in winter, so the beach is broad and offers easy strolling. A few bits of interstadial wood poke up out of the silt and sand, probably washed down from the area next to the glacier terminus where the stumps of this old forest still stand. Windrows of dead alder leaves lie a remarkable ten to fifteen feet into the brush above the upper limit of the beach, suggesting that there must have been a tumultuous day on the water not very long ago.

Four ravens were focused intently on something in one of the shallow streams that course over the beach to the lake. As we approached, the ravens backed away, revealing a female coho lying on her side in about an inch of water. She appeared to be a relatively recent arrival, with no fungal patches at all. But she was missing the eye on the upper side and her gills on that side had been torn up—we thought she was dead. But not quite—she could still move a bit, although her eggs were beginning leak out. Her minutes were clearly numbered, but we gently moved her into deeper water so those last minutes might be slightly more comfortable. Of course, the ravens came back as soon as we moved on and finished their meals. The big question for us was how she got into this sorry situation. There were no wounds indicating that a bear or eagle had tried to grab her but abandoned her there. Was she just a late arrival, trying to get up this little creek to spawn and finding the water too shallow?

There were a few bear tracks on the beach, not very recent ones. However, the bruins (probably) were still around, because a few days later I found two fresh-looking lower jaws of coho lying in the middle of the trail (and they had not been there on our earlier walk). Of course in the water there was no sign of the poor, mauled female we’d seen earlier.

An informal trail cuts up from the end of the beach to the West Glacier Trail and crosses a tiny stream. There we spotted a pair of very shy coho consorting, and we quickly departed, leaving them in peace.

On the way back on the main trail, we accidently spooked three ravens on a very small creek on the hillside. They were squabbling over something, which on closer inspection turned out to be the picked-over remains of another coho.

Other members of the feathered tribe included a flock of juncos in the beach-fringe alders (and they were still there a few days later), maybe collecting alder seeds, and a kingfisher who was annoyed by our passing near its hunting perch. At the little pond partway up the side of the rock peninsula, a dipper foraged along the edge, diving and swimming, for several minutes before departing downstream.

On another day, well up the Perseverance Trail, a dipper was foraging in fast water, dodging in and out among boulders. It then spent several minutes on a single large, flat rock with shallow water sheeting over it. The bird worked over the surface of that rock assiduously, picking up numerous miniscule prey items—so tiny that they could apparently be swallowed immediately, without mandibulation. Possibly blackfly larvae??

On yet another day, after enjoying some swans floating about on the far side of Windfall Lake, we had some fun with a make-believe critter on the trail. We couldn’t put a name to it, so we just called it Mossy. A Rip Van Winkle sort of critter, sleeping for a long time? An escapee from the Ark? An antediluvian creature revisiting the earth? As I said, November can be a rather slow time for little explorations, so imaginations went a tad wild.

The real excitement was in Auke Bay (and I wasn’t there): a friend recorded a gang of orcas attacking a couple of sea lions—circling, circling, head butting, body slamming from above and side, flipping out of the water, tail bashing. Then quiet, cruising back and forth, presumably grabbing the pieces, and the gulls came to get the scraps. Maybe I should be spending more time near the big water!

Today, my verbal rambling may match the real rambling!

Recent finds along the trail

eggs and erosion, flowers and porcupine nibbles

A stroll across Bridget Cove tide flats in early July brought us to a stand of eelgrass. To our surprise, the eelgrass was dotted with many thousands of fish eggs. We thought this was too late in the season for herring, but a forage-fish expert told me that herring have been known to spawn there in early July. The eggs would need to incubate for about two weeks (at a temperature of eight degrees centigrade) and the embryos of these eggs appeared to be in early stages of development. If we went back a week or so later, they probably would have hatched.

After the recent jökulhlaup, I went to inspect the ‘gooseneck’ area on the lower Mendenhall River, where a sweeping loop in the river has created a narrow peninsula just upstream from Vintage Park. I imagined that the big water coming down would have breached the really narrow part of the peninsula, flowing over the top and eroding at least an overflow channel. But no! There is indeed some new erosion of the bank on the upstream side. On top, trees now lean downstream, their roots tipping up and making large cracks in the soil; they will probably fall rather soon, reducing the top of the peninsula to just a couple of feet in width. Something to keep our eyes on!

Just on the other side of Cropley Lake, in a wet area, is a stand of pale yellow flowers. This is a species of fireweed called yellow fireweed or sometimes called yellow willowherb (Epilobium luteum). The familiar pink flowers of the usual fireweed (formerly a species of Epilobium but now reclassified in a separate genus, Chamaenerion) are evident all over town, but the yellow one is much rarer. We’ve seen small numbers of this in only a few places around here. It can propagate vegetatively, so once a plant gets established from seed, it can spread locally if the habitat is suitable. And by the way, why is the pollen of the pink fireweed sometimes blue-green?

Another familiar local plant is known as goatsbeard (Aruncus dioicus). This species is dioecious, bearing male and female flowers on different individuals. On a recent stroll up Perseverance Trail, we looked more closely at the narrow flowering tassels. Indeed, just as expected, males and females were distinguishable. However, we were interested to see that in a very few male plants, a small number of seed pods were developing on some of the tassels. I recall that some other reportedly dioecious plant species have similar transgender issues at least upon occasion. Because the female plants were well past flowering and had well-developed seed pods, we could not tell if any of them had once sported male parts.

On Gold Creek, a female harlequin duck was foraging, dipping and diving among the rocks. We enjoyed watching her skillful maneuvers, swimming upstream underwater, skittering rapidly on the surface of a broad, flat rapid, doing balanced skids on wet rocks, and ferrying across the fast chutes just like a kayaker or a canoeist would do. Humans may have learned this technique, long ago, from the ducks.

A friend reported a dipper nest in the spillway on Gold Creek, so I went to look. Sure enough, in a big crack in the concrete was a pile of moss with an opening through which I could see movement. Mama dipper was either incubating eggs or brooding chicks, while Papa was on guard on a boulder nearby. Later, I looked again, and now the adults were both outside, feeding three or four small, piping nestlings. Big loads of caddisfly larvae and other goodies went down the begging mouths. Very satisfying to observers, as well!

One day we walked on the sand flats of Eagle River along the Boy Scout Trail. There were small footprints in the sand, looking a bit like a baby’s foot but with five claw marks well ahead of the pad. Hmmmm, probably a porcupine. And presently we saw the perpetrator, busily nipping of the ends of beach greens (a.k.a. seabeach sandwort; Honkenya peploides) shoots. After some minutes, the critter bustled off toward the woods, and we went to look at the nibbled shoots. It had ignored the shoots with seed pods and seemed to have concentrated on the shoots with flowers.

This area of sand flats has many clumps of beach greens, whose shoots sprawl out in all directions. In one portion of this plant colony, most of the clumps had been rolled up from one side…the long shoots on that side were flopped over the ones on the other side, consistently in the same direction. We know from reports of other observers that porcupines sometimes roll up outdoor carpets and lick what is underneath. Could these plants reflect similar behavior? If so, what are the animals getting?

Thanks to Darcie Neff for information and references.