Beech, maple, lime tree, horse chestnut, hornbeam, elm and spruce (Figure 7.19).
Not too many, and not too vigorous. Absolutely under 25%, maybe even under 10%, of the canopy. Sometimes it is wise to avoid nursery species totally because they are often forgotten in the later thinning programs and thereby often become part of the later phases, thereby introducing an unwanted heterogeneity.
Closed edges, especially towards the south and west, are recommended to increase the sense of an inner room and darkness, but also to reduce processes which cause heterogeneity.
Field layer, type and establishment methods
A very poorly developed field layer or a field layer dominated by low perennials and mosses that will develop in the long term is likely to occur spontaneously. In order to introduce a more diverse spring and early summer flowering field layer, direct seeding and planting should be used.
Very short distance between the plants gives fewer forks at the stem and a higher inner roof, whereas a larger distance gives a lower inner roof, which will be a variant between the pillared hall character and another more open type.
Dark high woodland: an old beech stand
Dark high woodland: a horse chestnut stand in a park in Hanover,
Germany, giving the typical ‘pillared hall’ effect
The light high woodland