davidii – Jean Pierre Armand David (1826–1900), a Jesuit French missionary, who traveled to China initially to convert people to Catholicism but who ultimately focused on the natural history (plant and animal life) of the region and identified this species for western culture

Native range: Tibet (often listed as W. China)

Leaves:

• opposite
• simple
• elliptic to oval
• 2–6” long
• 1–2.5” wide
• distinctly 3-veined
• secondary veins like ladder between primary veins
• toothed towards apex
• dark-bluish green above
• paler below
• turn burgundy in fall
• leathery

Flowers:

• dioecious
• inflorescence – flat umbel-like, 2–3” wide
• no sterile outer flowers
• radial (actinomorphic)
• 5-lobed corolla
• 5 stamens
• white to pinkish

Fruit:

• drupe
• bright, metallic blue

Other characteristics:

• small shrub to 3–4 ft.
• evergreen
• warty branchlets

Relevant info:

• indestructible plant, good for parking lots (tolerates compacted soil and is low-growing)

Ecology & Adaptations:

• native to the hills of Tibet (per 1885 publication of description of new species)
• pollination:
  • many viburnums attract buttery adults, which feed on nectar and host larvae that feed on leaves
  • pollinated by insects and wind (male and female plant needed)
• seed dispersal – aided by birds that eat fruits
• shade tolerance:
  • leaf anatomy increases photosynthesis capacity – double layer of palisade mesophyll cells on upper side of leaves channel excess irradiance (sunlight energy) to the spongy mesophyll cells on underside of leaves
  • mesophyll cells scatter light throughout the leaf, maximizing absorption
  • elongated shape of palisade cells provides high cell SA:V, which benefits CO₂ diffusion to photosynthesizing chloroplasts
  • stomata are concentrated on the underside of the leaf, where the spongy mesophyll cells facilitate the diffusion of CO₂ through a network of air spaces