Bluff Lettuce

Dudleya farinosa

"Dudleya farinosa" is a species of succulent plant in the family Crassulaceae known by several common names, including bluff lettuce, powdery liveforever, and powdery dudleya. A coastal plant of northern California and southern Oregon, it is typically found on oceanic bluffs just directly above the reach of the waves.
Dudleya farinosa Garrapata State Park Trail, CA, US Dudleya farinosa,Fall,Geotagged,United States

Appearance

The plant's structures are borne from the thick, woody and succulent stems, which are otherwise known as caudices. As the plants are generally rooted in vertical bluffs and cliffs, the caudices in age become decumbent or pendent, hanging downwards from their point of origin. On the tip of the caudex is the rosette, which is a circular arrangement of the vegetative leaves. The older, outer leaves of the rosette dry out during the dormant season and are pushed backwards as the rosette and the stem grow forwards. This gives the species an abundance of dried and dead leaves covering the stem; distinguishing it from the relatively leafless stem of "Dudleya caespitosa".

Plants are usually seen with multiple rosettes and stems. Multiple rosettes and stems can be formed from a single plant by a process described as "multiplication by division," but better known as dichotomous branching. The primary rosette divides in the center and the two points eventually grow apart until they form two branches with their own rosettes. This process repeats continuously in this species, forming clumps of as little as 4 rosettes to large mats of up to 60 rosettes on a single plant. Branches only form apically, not from the axils.

A leaf-succulent, the rosettes consist of short, thick, and pointed leaves, sometimes covered heavily in a farina, or epicuticular wax, used to shield the plant from the sun and water. Another form of "D. farinosa" lacks the white wax, and presents with green and glossy foliage. Stress, cool wind, sunshine, and exposure can cause the edges or tips of the leaves to turn red, maroon or violet.

To sexually reproduce, before the summer the plant begins to erect a tall stalk that will bear flowers. The peduncle is covered in 20 to 35 leaves, similar in color to the vegetative leaves on the rosette. When the structure matures, the stalk divides into 3 to 5 branches that bear the flowers, giving an overall flat-topped shape to the flower-covered inflorescence topping the peduncle. The pale-yellow flowers, attached to tiny and erect stalks on the branches known as pedicels, face topside and have a somewhat tubular shape to them.Stems / caudices: The caudices are caespitose, branching apically and absent of axillary branches. They measure between 10–60 cm long and 1–3 cm wide, and are usually not elongate. The older parts of the stem are typically not visible between the dried leaves.

Rosettes: Plants have 4 to 60 rosettes, which measure 4–25 cm wide. The rosettes have 15 to 30 leaves.

Leaves: The leaves are evergreen, and may be gray or green, becoming reddish. They measure 2.5–6 cm long by 1–2.5 cm wide and 5–9 mm thick. The base of the leaf is 1–2.5 cm wide. The leaf shape is oblong-ovate, and the tip is acute or generally obtuse. The surfaces are sometimes farinose. The leaf margin tends to have 2 or more angles between the upper and lower faces of the leaf.

Inflorescence: The peduncle is 10–35 cm tall, and measures 3–8 mm wide. The peduncle then divides into 3 or 5 close-set branches, which may sometimes branch bifurcately themselves. The terminal branches measure 1–3.5 cm long, and are ascending in age. The terminal branches bear 3 to 11 flowers on them, on pedicels that are 1–3 mm long. The pedicels are erect and do not bend in fruit. The flowers face topside, and their terminal branches are not twisted.

Bracts: There are 20 to 35 bracts on the inflorescences. The bracts are arranging in a spreading fashion, and are shaped cordate-ovate, measuring 10–25 mm long by 10–20 mm wide, with an acute apex.

Flowers: The calyx measures 5–8 mm long by 5–6 mm wide. The sepals are 3–7 mm long, and are shaped dentate-ovate. The petals are 10–14 mm long by 3–5 mm wide, and are connate 1–2 mm. The petals are shaped oblanceolate, the apex acute to obtuse, the tips often out curved, and colored pale yellow. The upper margins of the adjacent petals are not touching. The corolla is loosely tubular, and not tightly pentagonal. The pistils are connivant and erect, and the follicles are erect.

Distribution

This section needs expansion. You can help by.
This plant is native to the coastline of parts of Oregon and northern California, where it is commonly found on bluffs and coastal hillsides. One specialized habitat in which "D. farinosa" is found is the Monterey Cypress forests at Point Lobos and Del Monte Forest in Monterey County, California.

Predators

This section needs expansion. You can help by.
Native plants are being dug up illegally in huge numbers, originally thought to satisfy demand as house plants in South Korea and China. Recent investigations show the demand may come from a smaller community of highly skilled succulent collectors and enthusiasts.

Evolution

This type specimen of this species was first collected by Theodor Hartweg around 1847, in a locality described as the "Rocks near Carmel Bay, California." A photograph of the type specimen, as well the description and type locality, indicates that the type was collected from the populations of this species growing on the rocky bluffs of the Monterey Peninsula. There, the species is well separated from "Dudleya caespitosa", as it grows only on the granitic rocks just above the reach of the waves, while "D. caespitose" is found more landwards and with a different morphology, namely more saturated yellow flowers, narrower, green leaves, and a more slender and less leafier inflorescence.

Based on Hartwig's collection, John Lindley described the species as "Echeveria farinosa." Lindley's description emphasizes the epicuticular wax on the leaves as "if they had been powdered with flour." He also notes the "remarkable whiteness" of the leaves and the pale lemon flowers as being two characters that clearly delimited the species. Lindley also described the basionym of "D. caespitose" on the same page.
† E. "farinosa "; caulescens, nana, foliis linguiformibus acutis planis candidis adultis viridibus, caule decumbente, racemis secundis corymbosopaniculatis, floribus pedunculatis.— John Lindley, The Journal of the Horticultural Society of London, v.4 p. 292

References:

Some text fragments are auto parsed from Wikipedia.

Status: Unknown
EX EW CR EN VU NT LC
Taxonomy
KingdomPlantae
DivisionAngiosperms
ClassEudicots
OrderSaxifragales
FamilyCrassulaceae
GenusDudleya
SpeciesD. farinosa