betulus – refers to the birch-like (Betula) morphological characteristics of this species

Native range: Europe to Iran, including Turkey & Ukraine

Leaves:

• alternate
• simple
• ovate-oblong
• 2–3 (5) inches (5–8[13] cm) long
• acute tip
• base rounded or subcordate
• conspicuously ribbed
• parallel, prominent, impressed veins (10–13 pairs)
• doubly serrate margin
• turning yellow in autumn
• brown leaves which stay attached, dropping only in spring when the new green leaves are starting to come out
• similar to those of the beech (Fagus sylvatica), but less shiny

Flowers:

• monoecious
• males:
  • loose catkins, up to 6 cm long
  • pendulous
  • 3 flowers per scale
  • 3 stamens
  • expanding in spring as yellow curtains
• catkins open in spring, followed by hop-like fruiting catkins to 8 cm
• females inflorescence to 15 cm (6”) long and 6 cm broad w/ green bracts 5 cm (2”) long
  • bracts 3-lobed and middle lobe is longer

Fruit:

• hard nut enclosed in a green leafy bract
• 8 pairs of nutlets, each pair at the base of a green leathery tri-lobate bract, 3.5 cm long

Other characteristics:

• tree 40–60 (70) ft.
• many upright branches, rounded canopy
• many branches occur low and in semi-whorled fashion on the trunk
• smooth grey bark
• trunk sometimes having a rippled muscular character to its surface contours (“musclewood” is a common name in Britain)

Relevant info:

• popular street tree, also used in parks and gardens
• common name, hornbeam, comes from the extremely hard wood of this tree that will take a horn-like polish and was once used in Europe to make yokes for oxen (the beam between the ox horns)
• also called ironwood due to very hard wood

Ecology & Adaptations:

• native from Europe to Iran, including Turkey and Ukraine from sea level to 700 m. in Central Europe, 1000 m in the Western Alps, and 1800 m. in Iran
• found in lowlands, hills and the low mountain belt in temperate climates
• high summer temperatures limit its distribution in the south
• deep moist and well-drained soils from sub-acid to calcareous, although can tolerate wet heavy clay to light dry sandy soils
• component of classic European temperate forest on fertile soils, as well as beech (Fagus sylvatica) forests
• pollinated by wind
• vegetative regeneration/reproduction - sprouts (suckers) from roots and epicormic buds in trunk
• herbivore/microbial defense – compounds (such as phenolic acids, flavonoid glycosides, tannins, and procyanidins) affect palatability, interfere with digestion, affect respiration of herbivores, and provide protection from microbial infection
• very shade tolerant:
  • morphological modifications in response to low light include thinner leaves in shaded vs. full-sun conditions, which minimizes investment per unit area in photosynthesizing structure
  • physiological modifications include lower photosynthetic capacity in shade leaves, based on both area and mass
• succession – can colonize open sites as well as be part of the understory