BitB Bits: April 2023

April 1—Better late than never. The serviceberries (Amelanchier arborea) in my neighborhood have finally started blooming, marking the beginning of a month-long period where three charismatic native trees bloom in rapid succession (redbuds will follow shortly, followed by dogwood—the king of native flowering trees in Missouri). I normally see serviceberries begin blooming in mid- to late March, but the weather of late has been mostly coldish and cloudy. First bloom on April Fools Day is about as late as I’ve ever seen for this species.

Amelanchier arborea (serviceberry) in dry-mesic upland deciduous forest (Wildwood, Missouri).

April 2—Pussytoes. Native wildflowers are springing fourth now that sunshine and balmy temps have returned. Today’s first bloom is pussytoes (Antennaria parlinii), also called mouse ears. Both common names refer to the fuzzy nature of the plant—the first in reference to its flowers and the second to its leaves. This plant was, until recently known as Antennaria plantaginifolia (meaning “plantain-like leaves”), but Missouri populations were recently deemed sufficiently distinct to warrant splitting from populations further west as a separate species. I always see these plants growing in dry(ish) upland forests, but always in a more exposed situation on rocky or sloping ground where they receive more sunshine and less moisture than typically found deeper inside the forest. These plants are growing along the roadside in a small rise in my neighborhood.

Antennaria parlinii (pussytoes) in dry-mesic upland deciduous forest (Wildwood, Missouri).

April 3—Mexican plum. On yesterday’s WGNSS Botany Group outing, we observed the spectacular blossoms of American plum (Prunus americana). There is, however, a very closely related species of wild plum in the state called Mexican plum (Prunus mexicana). The two species, both members of the rose family (Rosaceae), have identical blossoms and flower at exactly the same time, making them quite difficult to distinguish from each other. One character that can be used fairly reliably though is their growth habit. Mexican plum is usually more treelike, with isolated plants well separated from their nearest neighbors, while American plum tends to be shrubbier in form and forming clonal colonies with many individual plants densely occupying an area. There are several small trees along the road in my neighborhood, all of which exploded into full bloom starting yesterday, that I take to be Mexican plum owing to this individual treelike form of growth. The flowers of both species are highly attractive to pollinating insects, so I will be checking them closely over the next week while they are in bloom to see what insects I might be able to find upon them.

Prunus mexicana (Mexican plum) along edge of dry-mesic upland deciduous forest (Wildwood, Missouri).

April 5—Today’s first blooms: sassafras and sugar maple. It’s been a rapid fire sequence of blooms since warm temps returned a few days ago. Today’s first blooms include two native trees—one known for its spring flowers (sassafras), and another one not (sugar maple). Sassafras (Sassafras albidum) flowers aren’t as showy as those of other spring flowering trees—their yellow-green color just can’t compete with the delicate white of serviceberry, bold white of dogwood, or vivid pink of redbud, but they offer more botanical interest than their charismatic contemporaries in that trees are usually dioecious—i.e., trees usually have either male flowers only or female flowers only rather than both (a condition known as monoecious) or, more commonly, flowers with both male and female parts (also monoecious, but with “perfect” flowers). Flowers on both male and female trees have 5–6 “tepals” (i.e., petals plus petal-like sepals); however, male flowers have nine stamens (the male part of the flower) and a non-functional style (female part), while female flowers have only six non-functional stamens (i.e., “staminodes”) around the central style.

Sassafras albidum (sassafras) in dry-mesic upland deciduous forest. Sassafras trees are usually dioecious – this is a female as indicated by its flowers with six staminodes (aborted stamens) (male trees have flowers with nine stamens) (Wildwood, Missouri).
Sassafras albidum (sassafras) in dry-mesic upland deciduous forest. Sassafras trees are usually dioecious – this is a male as indicated by its flowers with nine stamens (female trees have flowers with six staminodes, which are aborted stamens) (Wildwood, Missouri).

Sugar maple (Acer saccharum) is not usually thought of as a “flowering” tree, but like all other broadleaf plants it possesses true flowers that produce seeds for reproduction. The flowers also appear in early spring on long stalks in drooping clusters. However, unlike sassafras, sugar maple can be either monoecious or dioecious, and in the latter case the flowers can be either imperfect or perfect. In other words, any given tree may have only male flowers or only female flowers (dioecious), or it may have both male flowers and female flowers (monoecious imperfect), or it may have flowers with both male and female parts (monoecious perfect).

Acer saccharum (sugar maple) in mesic upland deciduous forest (Wildwood, Missouri).

April 7—Woodland phlox. Now blooming in my woodland garden is woodland phlox (Phlox divaricata). This common spring wildflower is also sometimes called sweet William and blue phlox, but the flowers are more blue-purple than blue and can even be pink or white (plus, I don’t have the foggiest idea who “William” is!). The species epithet divaricata means “widely diverging” and refers to the more widely separated flowers compared to the usually tight clusters of flowers found in other species in the genus. There are a number of additional species in the genus in Missouri, but most of them have a restricted range in Missouri (usually restricted to parts of southern Missouri) or are found in non-woodland habitats. Phlox flowers are some of the most fragrant of our native wildflowers.

Phlox divaricata (wild blue phlox, woodland phlox, wild sweet william) in mesic upland deciduous forest (Wildwood, Missouri).

April 10—Brown stink bug. The most appropriately named insect in the world!

Euschiatus sp. (brown stink bug—family Pentatomidae) in dry upland deciduous forest (Lenexa, Kansas).

April 12—Violet wood-sorrel. Today’s native wildflower is violet wood-sorrel (Oxalis violacea). Many people know this plant due to the pleasantly tart flavor of the leaves and fruits when eaten. The taste is due to the presence of oxalic acid in the plant’s tissues, although it can be toxic if consumed in large quantity due to the formation of calcium oxalate crystals in the kidneys. In fact, the genus name derives from the Greek oxys meaning “sharp,” referring to the sharply sour taste of the leaves.

Oxalis violacea (violet wood-sorrel) in dry-mesic upland deciduous forest (Wildwood, Missouri).

April 12—Bridge of spiders. The Boone Bridge spiders have returned. Best I can tell they are orb weavers in the genus Larinoides (a.k.a. furrow spiders). Like most orb weavers, these spiders build a new web each night and consume it the next morning, then start all over again the next evening. Males can be distinguished by their enlarged pedipalps.

Larinoides sp. (furrow spiders—family Araneae) on web over Missouri River (Chesterfield, Missouri).

April 15—“Hey, Iris… what is the definition of dyslexia?” Not sure why she won’t answer—-maybe my iPhone is broken!

Iris sp. (cultivated iris) in woodland garden in mesic upland deciduous forest (Wildwood, Missouri).

April 16—Virginia bluebells. One of my favorite native wildflowers is Virginia bluebells (Mertensia virginica). There is but a single specimen of this fantastic species in the woodland gardens around my home, but it blooms reliably every spring showy as ever. Virginia bluebells are normally found in bottomland forests in rich soil along creek beds, so I suspect this lone individual might have been planted by a previous owner. I thank them if they did.

Mertensia virginica (Virginia bluebells) in mesic upland deciduous forest (Wildwood, Missouri).

April 18—Dogs in bloom. Our most iconic native flowering tree may well be flowering dogwood (Cornus florida). Its white showy blossoms not only grace the forests of southern Missouri, but also neighborhoods and gardens throughout the state. An interesting “factoid” about this species is that the large white “flower” is not a flower at all, but rather an inflorescence composed of many individual flowers (called “florets”) that, together, form the central yellow disc of the “flower.” The four white “petals” surrounding each inflorescence also are not true petals or even parts of flowers that can sometimes look like petals, but rather are modified leaves called “bracts” that serve the functional purpose of petals (i.e., attracting insects to the flowers for pollination). In the photo, you can see some of the individual florets are open, revealing four male stamens surrounding a central female pistil, while other florets are still closed. The florets do not actually begin opening until after the white bracts surrounding the inflorescence have opened. Thus, for a time when the bracts first open, the tree looks like it is in flower but technically is not yet. (Pull that up in dinner conversation sometime. You’re welcome.)

Cornus florida (flowering dogwood) in mesic upland deciduous forest (Wildwood, Missouri).

©️ Ted C. MacRae 2023

Muir Woods National Monument

This is the best tree-lovers monument that could possibly be found in all the forests of the world. – John Muir

Coastal redwood (Sequoia sempervirens) is the tallest type of tree in the world, with maximum recorded heights approaching 380 feet. This majestic conifer grows only along the Pacific Coast in a narrow strip from Monterey to Oregon. Most of the estimated 2 million acres of original redwood forest are now gone — victims of the saw! One of the small groves that managed to escape this fate due to its relative inaccessibility grows along Redwood Creek and adjacent slopes in what is now Muir Woods National Monument. At heights approaching 260 feet, the redwoods growing here are not the tallest to be found; however, their proximity to San Francisco (just 15 miles from the Golden Gate Bridge) makes them the most heavily viewed examples of this ancient tree. Lynne and I visited Muir Woods a few times in the 90’s after moving to Sacramento — today (3/20) was our first visit since then, and the first ever for Mollie and Madison. In addition to getting to see these marvelous trees once again, we were also treated to a spectacular display of spring wildflowers.

We began our hike on the main paved trail. This is where most visitors confine themselves during a visit to this place, so the picture here documents a rare sight — no people! I apologize for its lack of focus, a consequence of the limitations of my little point-and-shoot camera in the limited amount of light that makes it through these towering trees during late afternoon.

Standing beneath one of these trees and looking up is a lesson in insignificance — the feeling one gets looking straight up the trunk of one of these giants cannot be adequately captured on film (er… microchip).

We quickly tired of the crowds and decided to hike up the Ocean View Trail, which climbs quite steeply up the east side of the valley. This marvelous trail was nearly devoid of people, and we found ourselves winding through thick, dark, cool forest with numerous side ravines. The lower elevations of the trail were dominated by redwood trees and a spectacular array of spring wildflowers. Among the most common was California toothwort (Cardamine  californica [=Dentaria californica]), a member of the mustard family (Brassicaceae). I noticed that the leaves at the base of the plant were broad and oval, while those arising from the flower stalk were slender and lanceolate, often divided into 3 leaflets.

Wake robins (genus Trillium), belonging to the lily family (Liliaceae, sometimes separated into the lily-of-the-valley family, Convallariaceae), are among my favorite wildflowers. We soon noticed Western wake robin (Trillium ovatum) growing commonly in shaded areas along the trail. We were also seeing some purple-flowered wake robins — at first I thought they were a different species, but it soon became apparent that these were older Western wake robin flowers, which change color from white to purple as they age.

A little further up the trail we began encountering small patches of Mountain iris (Iris douglasiana, family Iridaceae). Flower color for this native species ranges from cream-white to lavender, but all of the flowers we saw were of the white variety.

We saw this fat Solomon’s seal (Maianthemum racemosum ssp. amplexicaule [=Smilacina racemosa var. amplexicaulis]) growing in one of the cool, moist, side ravines. This is another member of the Liliaceae (sometimes separated into the Convallariaceae). The large, oval leaves clasping around the distinct, unbranched stem were almost as attractive as the flowers, which apparently give rise to bright scarlet berries in the summer.

In the middle elevations the redwood forest transitioned to drier oak woodland containing a mixture of Douglas-fir (Pseudotsuga menziesii), Pacific madrone (Arbutus menziesii), bigleaf maple (Acer macrophyllum), and tan oak (Lithocarpus densiflorus). Some of the Douglas-firs were enormous.


Indian warrior (Pedicularis densiflora) is a member of the figwort family (Scrophulariaceae, sometimes separated into the Orobanchaceae). This plant, with its striking bright red flowers and finely divided, fern-like leaves, is a facultative parasite on the roots of other plants. Apparently, the genus name refers to an old superstition that sheep could become infested with lice if they ate this plant.


The juncture of the Ocean View Trail with the Lost Trail was closed, so we backtracked down the 1+ miles back to the main paved trail. By now it was fairly late in the afternoon, and the crowds had thinned considerably. Having gotten lots of good views of the giant trees, we began turning our attention downwards to the smaller understory flora. Ferns, of course, are a dominant component of this understory, especially along Redwood Creek. This large specimen may represent Western sword fern (Polystichum munitum) (family Dryopteridaceae), which can apparently be distinguished by small hilt-like projections from the base of the pinnae (leaflets), but I couldn’t get close enough to see for sure.


Abundant on the ground in the valley was redwood sorrell (Oxalis oregana), a member of the family Oxalidaceae. In places this plant covered the ground in thick carpets.


Among the more interesting plants we saw in the valley was California fetid adder’s tongue (Scoliopus bigelovii), yet another member of the Liliaceae or Convallariaceae. I wasn’t sure what this plant was at first, despite its highly distinctive, glossy, mottled foliage. We were too late to see the blooms, which apparently have a fetid odor to attract flies for pollination, but did find the maturing pods on their slender, drooping stems.


Close to the creek’s edge we saw this colony of horsetails (Equisetum sp.), primitive plants in the family Equisetaceae. Members of this group belong to one of the most ancient lineages of vascular plants, dating back to the Devonian period (416-359 million years ago). Their Paleozoic ancestors (Calamitaceae and Archaeocalamitaceae) were giants, reaching heights of 50 ft or more, and were major components of the Carboniferous swamplands. Along with lycopod trees (Lepidodendrales), they were important contributors to coal formation and, like the lycopods, became extinct by the mid-Permian (~270 million years ago). The genus Equisetum represents the only surviving descendants of this lineage. Unlike their extinct progenitors, these small, herbaceous plants rarely exceed 4 ft in height; however, they share many of the same characters such as articulate stems with microphylls arranged in whorls. Recent phylogenetic studies, using both molecular and morphological characters, suggest that horsetails, together with ferns, form a clade representing one of the three major lineages of vascular plants (Pryer et al. 2001).


Nearby we saw a patch of Giant wake robin (Trillium chloropetalum) in flower. These were taller than the California wake robins we saw on the slopes of the Ocean View Trail but similarly characterized by a whorl of 3 leaves and flowers composed of 3 erect petals. Mature flowers darken to a deep red purple, so it seems these plants had just begun flowering. Muir Woods appears to be a good place for observing a diversity of Convallariaceae!


Also along Redwood Creek we found this bigleaf maple (Acer macrophyllum) in full bloom. As its specific epithet suggests, this maple has the largest leaves of any member of the genus — in this example the newly-expanded leaves were distinctly purplish. The picture below shows the greenish-yellow flowers (petals inconspicuous) produced on long, pendulous racemes.


Interpretive signs along the paved main trail pointed out a redwood “family group,” formed by sprouts growing from the base of a larger tree. Eventually, the central “mother” tree died and decayed away, leaving a ring of offspring that mature into an enormous, characteristic circle of trees. This apparently also happens with other types of trees, though on a smaller scale, as demonstrated in this picture of an oak (Quercus sp.) family group.


As the day drew to a close we found ourselves back in the parking lot, where this California icon, a clump of Coast live oak (Quercus agrifolia), was spreading its wide, majestic crown from multiple, twisted trunks and gnarled branches.


Much too soon, it was time to leave this beautiful valley, but before heading back to Sacramento we stopped to take one last look down towards the valley and out to the Pacific Ocean from the Panoramic Highway.