Fagus is a genus
of 10 species of deciduous forest trees widely distributed in
temperate regions of the Northern hemisphere. The common or European
beech (Fagus sylvatica) is one of our most important native species
in the UK; the Japanese beech (Fagus crenata) is very closely
related. If grown as solitary specimen trees, both species mature
into tall stately trees with a spherical crown and branches that
reach down to the ground. The bark is grey in the European beech
and silvery in the Japanese species; but remains smooth even on
very old specimens of both species.
Tiny monoecious flowers of both sex appear with the leaves in Spring and are pollinated by the wind. In Autumn they form nuts which are commonly referred to as beechmast. Leaves are arranged alternatively; the European species has ovate, wavy-edged leaves to 10cm which are pale green in Spring appearing as late as May in the UK, turning glossy green in Summer and then to yellow to orange-brown in Autumn. The browned foliage commonly remains on the tree throughout the winter protecting the following years leaf-buds, sometimes not dropping until the following Spring. The Japanese beech, Fagus crenata has these same characteristics but its leaves are slightly smaller.
Though it is Fagus sylvatica and Fagus crenata that are the two Fagus species seen as bonsai; there is good potential for other Fagus species to make quality bonsai. It should be noted that except for Fagus sylvatica, Beech require long, warm summers to thrive and in parts of Northern Europe the relatively short summers can be disadvantageous to vigorous growth.
Beech species and Hornbeams (Carpinus species) are often confused as they have many similarities particularly in their leaf appearance; the simplest way to differentiate them is to inspect the trunk; Beech have an entirely smooth bark whilst Hornbeams develop silvery veins on the surface of their bark.
BONSAI CULTIVATION NOTES
POSITION Beech will grow
happily in semi-shade or full sun; they do however require a position
sheltered from the strong midday sun of the summer and from strong
winds, both of which can cause leaves to scorch and brown. In
conditions where there is strong sunlight or strong wind, Beech
require more generous quantities of water especially if planted
in a shallow pot. Frost protection is required when temperatures
reach -5°C or less.
FEEDING For refined trees it is better to withhold fertilising for 3-4 weeks after leaves appear in Spring to keep the vigorous Spring growth finer with shorter internodes; after this initial strong growth, feed fortnightly until late Summer. For trees where trunk or primary branch development is still taking place feed as soon as leaves start to unfurl.
REPOTTING Every two years in Spring as the buds extend, use basic soil mix. Older specimens can be repotted as and when necessary.
PRUNING The main growth spurt for beech is in the Spring; to improve ramification of branches it is important to pinch out the growth tip after the first or second leaf emerges, this will greatly reduce the internodal length. Allowing the shoot to extend will result in coarse growth with long internodes (though this should be allowed if trying to thicken trunks or primary branches in young trees). After Spring growth has fully extended, prune back to a bud that is facing the way you wish future growth to head. Hard pruning can be carried out in late-winter or mid-summer. Removal of large branches can be carried out in midsummer to accelerate wound healing.
For more details
see Advanced Pruning Techniques
for European Beech
Wiring needs to be carried out with great care as the bark marks very easily and wire marks can take an extremely long time to fully disappear from the smooth bark surface. Branches suddenly thicken after spring growth and wire can cut into the bark in a matter of days. Try to make use of guy wires to move branches into shape if at all possible.
PROPAGATION Sow seed outside in Autumn or after winter stratification in Spring. Air-layer in late-Spring after spring growth has hardened.
PESTS AND DISEASES Aphids, bark scale and powdery mildew.
STYLING Beech suit all formal and informal upright forms in medium to extra large sizes. Beech are slow-growing and creating a large-trunked bonsai is a slow process. For this reason, beech are commonly seen in group plantings as trees with relatively thin trunks can be used to good effect.