WHAT IS STUMPING?
"Stumping", or "stumping back" is the practice of removing top growth at, or a few years after planting to stimulate a vigorous new shoot. It is usually done to improve the form of the young trees. It is, in particular, a traditional method of improving poorly formed oak after, for example, repeated frosting (Evans 1984). Except that it occurs earlier in the life of the tree, it is exactly the same as coppicing in that it relies on stimulating the growth of shoots from concealed dormant buds. On the whole Q. petraea coppices more freely than Q. Robur (Jones 1959).
TIME OF YEAR FOR STUMPING
The best time of year for cutting coppice to ensure plentiful regrowth and to minimise damage both to the stump and to the new shoots by frost, is while the trees are dormant, but only a few weeks before the buds begin to swell in the spring (March and early April). At this time reserves of carbohydrates in the roots are high but they fall to low levels immediately after the formation of new leaves and shoots (Evans 1984, Smith 1986). Shoots should be singled to one in summer (Evans 1984). Autumn cutting inevitably results in some separation of the bark (and cambium) from the wood over the following winter, and some stools are killed outright. It also results in a somewhat earlier start to growth in the spring and so shoots are more liable to damage by late spring frosts. Blake (1983) cites many examples of species coppicing best, in terms of survival, number of shoots and shoot weight, if cut in winter and worst in summer.
Possibly the first forestry experiment in Britain, in 1351, aimed to detect the optimum stool height in coppice (Linnard 1982). It is desirable to cut as close to the ground as possible (preferably within 2-3 cm) because the shoots are then more likely to develop independent root systems. This is believed to reduce the entry of disease into the stems and was the former practice in well-tended coppice (Jones 1959).
The cut surface produced by removing a stem is exposed to the elements which can result in damage to the wood and cambium near it through drying and the entry of disease. This reduces the reproductive potential by killing the buds which produce the shoots. Although damage cannot be completely prevented, its extent can be reduced by careful cutting. Schlich (1899) stated that the cut surface should be smooth and slanting so it sheds rainwater. Wood and bark should have the same slope and great care should be taken not to separate the bark from the wood around the edge of the cut. To achieve this, cuts should be clean and preferably made with a saw: even a chain saw is said to be preferable to using an axe. It is also usually recommended that cuts should be south-facing so that they dry quickly after rain (Harmer and Howe 2003)
- Blake, T.J. (1983). Coppice systems for short rotation intensive forestry: The influence of cultural, seasonal and plant factors. Australian Forest Research 13, 279-291.
- Evans, J. (1984). Silviculture of broadleaved woodland. Forestry Commission Bulletin 62, p. 33.
- Harmer, R. and Howe, J. (2003). The silviculture and management of coppice woodlands. Forestry Commission, Edinburgh.
- Jones, E.W. (1959). Biological flora of the British Isles: Quercus L. Journal of Ecology 47, (1), 169-222.
- Linnard, W. (1982). Welsh woods and forests: history and utilization. National museum of Wales, Cardiff.
- Schlich, W. (1899). A manual of forestry. Bradbury, Agnew and Co., London.