European beech

Identification and origin

Fagus sylvatica belongs to the Fagaceae, the oak and chestnut family. Its very large native range is centered on central and western Europe, stretching from Great Britain and southern Scandinavia to the Pyrenees, the Cantabrian Mountains, the Balkans and Crimea. In the southeast it hybridizes with Oriental beech, Fagus orientalis. It grows wild in woodland on well-drained soils, especially in hills and mountains, and is not at home on poorly drained soils or low-lying plains. Its species name, sylvatica, means “growing in the woods.” Colonists brought it to North America in the mid-1700s.

It is a large deciduous tree with a short trunk, often branching low, and a dense, oval to rounded crown. In cultivation it usually reaches 50–60 ft tall and 35–50 ft wide; in forests it can reach 164 ft. It grows slowly and lives long: in the UK, 250 to 300 years is already a good age, and trees older than about 200 years can die suddenly.

Its thin, smooth gray bark stays smooth into old age and is often compared to elephant hide. It is the easiest way to tell beech from hornbeam, whose bark is rougher and veined. The slender, zigzag twigs carry long, narrow, pointed buds covered in scales.

The alternate, simple leaves are oval to elliptic and about 1–4 in long. They have five to eight pairs of parallel veins and a wavy edge fringed with silky hairs when young. Pale green in spring, glossy dark green in summer and paler underneath, they turn yellow, golden bronze or russet in fall. Many stay on the twigs, dry, all winter long: this is called marcescence, and it is especially visible on clipped hedges.

The inconspicuous flowers appear in spring on the same tree: greenish-yellow male flowers in drooping round clusters and reddish-brown female flowers in short spikes. A beech might not flower until it is 30 to 80 years old. The fruits, beechnuts, are small triangular brown nuts about 1 in long, usually in pairs inside a bristly husk about 1 in long that splits into four sections in fall. Birds, squirrels and other small mammals eat them.

There are a great many cultivars: purple beeches of the Purpurea Group, such as ‘Riversii’, with purple leaves that turn coppery in fall; columnar ‘Dawyck’ and ‘Dawyck Purple’; weeping ‘Pendula’; fern-leaved ‘Asplenifolia’; ‘Tricolor’, purple edged in pink; and twisted ‘Tortuosa’.

Light

Beech grows in full sun or part shade, with at least four hours of direct light a day. Variegated and pink-edged cultivars such as ‘Tricolor’ and ‘Roseomarginata’ prefer light shade during the hottest hours to avoid scorch. As a bonsai, shelter the tree from strong midday summer sun and from strong wind, both of which dry out and brown the leaves.

Watering

Beech likes soil that stays moist and is fairly sensitive to drought. In the ground, water thoroughly during dry spells, especially young trees. Mulch helps conserve moisture and moderates soil temperature. Its shallow roots make it vulnerable to severe droughts, which can kill old, already stressed trees.

In a container, water as soon as the surface of the mix starts to dry. Never let the root ball dry out completely, but do not keep it soggy either: excess water rots the roots. Full sun and wind raise its needs a great deal, especially in a shallow pot. Avoid very hard water, which eventually causes chlorosis.

Potting mix

Beech prefers deep, moist, well-drained soil rich in organic matter; loam, sand or shallow rocky soils all suit it. It tolerates acidic, neutral and alkaline soils. It does not tolerate soggy, poorly drained or compacted soil, so keep foot traffic off the root zone and avoid city plantings, where it performs poorly. For a bonsai, a standard, free-draining bonsai mix is enough.

Temperature

This is a very hardy tree, suited to USDA zones 4a to 7b, that withstands Europe’s harshest winters. Its weak point is heat: it does not tolerate hot summers, and in the United States it becomes increasingly unsuitable south of Maryland. Hotter, drier summers could confine it to cooler, moister areas. In a container it stays outdoors all year, but the root ball must be protected from frost.

Repotting

In the ground, opinions differ on how well it recovers from transplanting: some references call it difficult, others easy. It is therefore best to choose its permanent spot carefully. As a bonsai, repot every two years in spring, just as the buds start to extend; older trees are repotted less often, as needed.

Pruning

Beech takes pruning well and makes excellent hedges of any size; a famous hedge in Perthshire, Scotland, is 1,739 ft long and averages 98.5 ft tall. A clipped hedge keeps its dry leaves through winter. On a bonsai, heavy pruning is done in late winter or midsummer; a large branch is best removed in midsummer so the wound heals faster. In fall and winter, always leave buds on pruned twigs, or they will die back.

Propagation

Seed is the recommended method: sow beechnuts outdoors in fall, or in spring after cold stratification over winter. Cuttings root poorly, and air layering, which can be done in late spring on growth that has hardened, does not always succeed.

Common problems

Beech has no serious pests, but the same symptom can have several causes: brown leaves can come from sunscald, wind, drought or overwatering. Look at the whole tree and its growing conditions before acting.

• Pests: aphids, scale, whiteflies, mealybugs, caterpillars and Japanese beetles; borers can attack stressed trees. Gray squirrels damage young plantings.
• Diseases: powdery mildew, cankers and beech bark disease; root rot from overwatering.
• Growing conditions: summer heat, soggy or compacted soil, and very hard water, which causes chlorosis.

Toxicity

Beech has low toxicity, limited to its fruits. Eaten raw or unripe in large amounts, beechnuts can cause vomiting, diarrhea, abdominal pain and nausea in people and dogs; they contain trimethylamine and oxalic acid. Cooked, they are edible. No contact dermatitis has been reported. Keep an eye on children and dogs that pick up fallen beechnuts.