Today's entry was written by Claire:

This serene photograph of an enchanted forest on the Olympic Peninsula was submitted via the BPotD Submissions Forum by ferngirl42 of Seattle, WA.

If you are familiar with Pacific coastal forests in the continental northwest US, you'll know rainfall is one of the major factors in forest density and composition. The annual rainfall in some areas exceeds 350cm (~ 12ft.), permitting blanketing forests consisting mainly of western hemlock (Tsuga heterophylla), western red cedar (Thuja plicata) and Sitka spruce (Picea sitchensis). The vegetation cover is so dense, hardly any sunlight pierces through the canopy. Close to the shoreline, though, the forest stalls, and light penetrates to the forest floor.

Near the shoreline, the Sitka spruce are not only exposed to the light, but also to the constant salt-laced maritime breeze (and sometimes ravaging winds). The burls (or burrs) are wood deformations caused by a stress to the growing tips of the plant. Some hypothesize that the salt-laced wind is responsible for burl formation in these Sitka spruces, others suggest viral or fungal damage. In general, the largest burls are found further south on coast redwoods (Sequoia sempervirens), but the first and second largest burls known are on display in British Columbia, at Port McNeill, with the largest weighing in at 30,481kg (69,200lb).

In the thread posting, ferngirl42 also makes mention of searching in this area for Polypodium scouleri, a fern commonly known as leathery polypody. Scouler's polypody (named for John Scouler), or leather-leaf fern, can be found across the western coast of North America. It is sometimes epiphytic, and ferngirl42 notes that she has found it growing on the burls of these huge conifers.

I mentioned in a previous Cercis entry a couple years ago about regretting not photographing Cercis occidentalis while in northern California, so I made sure to do so on this past trip.

Western redbud is native to southwest USA, including California, Arizona, Nevada and Utah. Like other Cercis species, it exhibits cauliflory, i.e., flowers emerge from the woody tissue of branches and stems (see previous entry for additional links on this phenomenon).

Despite there being two Cercis species in North America (the other being the eastern North American Cercis canadensis), these two taxa are not as closely related to each other as Cercis canadensis is to Cercis siliquastrum, a native of southern Europe and western Asia. An examination of the evolutionary relationships and biogeography within Cercis was done by Charles C. Davis et al. in 2002 (Phylogeny and Biogeography of Cercis (Fabaceae): Evidence from Nuclear Ribosomal ITS and Chloroplast ndhF Sequence Data in Systematic Botany 27(2):289-302). The precise reason for the close relationship between Cercis canadensis (a species of temperate climates) and Cercis siliquastrum (a species of dry Mediterranean climates) remains unknown, but most theories suggest a common arid-growing ancestor with later evolution in the Cercis canadensis lineage to become the temperate climate species observed today.

Thanks again to buildingadesert@Flickr, aka Claire W., for contributing an image to Botany Photo of the Day (via the BPotD Flickr Pool (original image)).

Cyclopia pubescens is a small shrub native to the Cape Province of South Africa. It belongs to a closely-related group of plants collectively known as the honeybush teas (see profile of Cyclopia genistoides on PlantzAfrica).

There is little information specifically about Cyclopia pubescens on the web, unless one does a little digging and discovers this 2008 thesis by Nicole Du Toit: Molecular phylogenetics of Cyclopia Vent.and its position within Podalyrieae (Fabaceae). Included within this thesis are photographs of Cyclopia species, including Cyclopia pubescens (PDF) and habit and geographical distribution information (PDF). This latter reference reveals that Cyclopia pubescens is "A rare and highly localized species that has only been recorded from the foot of the Vanstadens River Mountain west of Port Elizabeth, growing in marshy areas."

Thanks to Douglas Justice for writing today's entry. The photographs are from my recent trip to California. Douglas writes:

Up until 2006 and the publication of a paper by D. P. Little, the genus Cupressus L. was thought to be a northern Hemishere genus distributed roughly evenly (in numbers of species) between the Old and New Worlds. However, the New World cypresses (including Cupressus nootkatensis and the northern Vietnamese Cupressus vietnamensis) are now believed to be more closely related to the genus Juniperus than to the Old Word cypresses. You can read more about this change and the possibility of further name changes here.

Whatever name is applied to this species, it is a beautiful and iconic tree, forming huge, densely layered crowns with often picturesque twisted stems and braided bark. In the wild, it is known only from the Monterey Penninsula on the central California coast (see Cupressus macrocarpa on Wikipedia), but it is now very widely grown in horticulture. In gardens, it is primarily valued for its dark, dense foliage and fast growth for screens and windbreaks, but there are numerous mutant forms with a variety of branching and foliage effects (weeping, fastigiate, golden, etc.) and these appear to be extremely popular as specimen and accent plants. Despite the name, the cones of Callitropsis macrocarpa are not the largest of the cypresses. They are somewhat smaller than those of Callitropsis guadelupensis, a species from the island of Guadelupe, off the coast of Baja Cailfornia (and also smaller than those of the Italian cypress, Cupressus sempervirens). See a cone size comparison via Michael P. Frankis's wonderful cone collection.

Callitropsis macrocarpa grows well where winters are mild and there is plenty of humidity, tolerating wind and salt well, but the species doesn't fare well at all in areas with both high summer heat and humidity. Monterey cypress is the parent of the formidable Callitropsis × leylandii (C. nootkatensis × C. macrocarpa) (syn: ×Cupressocyparis leylandii), Leyland cypress, to which it lends considerable influence (most would be hard-pressed to guess the other parent from the appearance of this hybrid). Locally, both the species and its hybrids are susceptible to cypress tip moth (Argyresthia cupressella) and to cypress canker (Seiridium cardinale), but only where summers are hot (see this Australian fact sheet on cypress canker).

A contribution from fancymefoxy@Flickr gives us today's photograph to add to the series on tropical (and subtropical) fruits (original | BPotD Flickr Group Pool). Thank you!

Loquat is a member of the rose family, and native to southeastern China and (possibly) Japan. Read more via Fruits of Warm Climates: Eriobotrya japonica.

In February 3rd's BPotD entry on Erica plukenetii, I asked as an aside if anyone wanted to suggest which genus of plants in British Columbia had the most species. My one hint was a speculation that the same genus likely has the most species diversity in much of Canada and northern US.

Although Eurasian in distribution (but growing successfully in the Alpine Garden), the genus of this plant is the answer to that question: Carex, or the true sedges. This particular species is commonly known as mountain sedge (a literal translation of the Latin epithet montana) or soft-leaved sedge. Not knowing the common name at the time of the photograph, I didn't take the opportunity to test the texture of the leaves; in general, leaves of plants in the genus Carex contain silica bodies and are most decidedly not soft. Considering that silica is a component in glass production, you will likely find it believable that handling the leaves of some sedges can cut your hands in a manner akin to papercuts.

Botany resource link: Interested in tracking down books about particular groups of plants? Royal Botanic Gardens, Kew has merged its bibliographic databases creating a one-stop search tool: Kew Bibliographic Databases.