A large deciduous tree 80 ft and upwards high in the wild; young shoots clothed with small brownish hairs; winter-buds 1⁄4 in. long, slender, pointed. Leaves oblong or narrowly oval, blunt or rounded at the apex, rounded or broadly wedgeshaped at the base, very finely toothed, 11⁄2 to 4 in. long, 3⁄4 to 11⁄2 in. wide, yellowish green above and downy, especially on the midrib and on the raised part of the blade between the sunken veins; paler green beneath and downy on the midrib and veins; stalk 1⁄12 to 3⁄16 in. long, hairy. Veins fourteen to eighteen each side of the midrib, parallel, sunken above, prominent beneath. Husks about 3⁄8 in. long, the four valves ornamented with conspicuous toothed or fringed glandular appendages.
Native of the Chilean Andes from 35° 30′ S. to just south of 40° S.; it also occurs in the coastal range and has a few stands in Argentina near the Chilean frontier. It was introduced to Britain in 1910 by F. R. S. Balfour of Dawyck, who distributed plants from 1914 onwards. There was also an introduction to Kew in 1913, in which year W. J. Bean received a share of the seeds imported by the Dendrological Society of France.
The rauli is perhaps the most valuable of Chilean forest trees, ready for felling when seventy to ninety years old and yielding a timber not unlike that of the common beech. Unfortunately it has the smallest natural area of the deciduous species (apart from the local endemics N. glauca and N. alessandrii) and this has been much reduced by over-exploitation. The best stands are now confined to the Andes between 38° S. and 40° S., where it forms forests with the evergreen N. dombeyi or sometimes with N. obliqua. For the most part, however, it grows at higher altitudes than N. obliqua, and seems to be at its optimum in cooler and moister conditions than that species demands.
N. procera is distinct from all the other deciduous southern beeches in its large, conspicuously ribbed leaves, which resemble those of a hornbeam or Alnus firma. It is a quick-growing tree in the rainier parts of the British Isles, remarkable in its early years for its mast-like stem evenly tapered from the base and its slender, ascending branches. The tree in the Winkworth Arboretum, only thirty-six years old, shows what a fine specimen it makes when grown on its own, and how quickly. The leaves often turn to shades of yellow, orange, and red in the autumn. There have been casualties among young trees in exceptionally severe winters, but on the whole the rauli can be considered as hardy in this country. Good crops of seed are occasionally produced by trees over twenty years of age, and afford the best means of increase. It can also be propagated by means of cuttings put into gentle heat in July or August.
The following is a selection from the older trees in this country, none of which, it should be borne in mind, can have been planted before 1914: Kew, 47 × 33⁄4 ft and 36 × 31⁄2 ft (1957); Wakehurst Place, Sussex, 56 × 83⁄4 ft (1968); Leonardslee, Sussex, 88 × 63⁄4 ft and 70 × 61⁄4 ft (1970); Borde Hill, Sussex, 75 × 71⁄4 ft in Lullings Ghyll (1967) and 63 × 43⁄4 ft in Little Bentley Wood (1968); Winkworth Arboretum, Surrey, pl. 1937, 65 × 61⁄2 ft (1969); Westonbirt, Glos., in Victory Glade, pl. 1915, 85 × 61⁄2 ft (1969); Exbury, Hants, 56 × 51⁄2 ft (1968); Caerhays, Cornwall, pl. 1920, 74 × 63⁄4 ft and 66 × 81⁄2 ft (1971); East Bergholt Place, Suffolk, pl. c. 1915, 85 × 91⁄4 ft (1972); Muncaster Castle, Cumb., pl. 1923, 82 × 81⁄4 ft (1971); Edinburgh Botanic Garden, 54 × 53⁄4 ft (1970); Brodick, Isle of Arran, 60 × 91⁄4 ft (1965); Castle Kennedy, Wigtons., 73 × 63⁄4 ft (1967); Benmore, Argyll, 75 × 7 ft (1970); Glendoick, Perths., pl. 1929, 74 × 63⁄4 ft (1970).
The following measurements show the rapid growth of young trees: Queenswood, Heref., pl. 1960, 38 × 21⁄4 ft (1970); Tavistock Woods, Devon, pl. 1961, 51 × 13⁄4 ft (1970, measd. by Lord Bradford); Rheidol, Cards., pl. 1956, 60 × 3 ft (1971).
N. procera is of great promise as a forestry tree in Britain, but its use is still limited by scarcity of seed, which is exceedingly difficult to procure from Chile. Home-raised seed is available in very small amounts but should become more plentiful when the plots planted in 1955 and 1956 start to bear fruit. At present only six plots are more than twenty-eight years old. The total area of existing plots in England, Scotland, and Wales is 28 acres (1971, excluding private estates). The rauli succeeds best where the rainfall is 30 in. and over, and should not be planted in valley bottoms and lower slopes, nor on sites exposed to cold winds.
N. obliqua also has a future as a plantation tree, though its timber is slightly inferior to that of the rauli, and it does not have the slender, lightly branched and perfect stem-development of its sister species. On the other hand, it succeeds in eastern England where the rainfall is too low for the best development of rauli, and has the ability to thrive on a wide range of soils, including the poor sandy soil of the National Pinetum at Bedgebury, Kent. The trial plots cover 34 acres (1971). Home-raised seed is relatively abundant, and has given results superior to that from wild-source seed.
For further information, see: M. Nimmo, Nothofagus Plantations in Great Britain (For. Comm. For. Rec. No. 79, 1971), on which the above note is based.
N. alpina (Poepp. & Endl.) Krasser F. alpina Poepp. & Endl. – This species was described simultaneously with N. procera and is very probably a small-leaved form of it. The two have in fact been united by the Chilean botanist Dr Muñoz Pizarro under the name N. alpina, and this name would have to be accepted if indeed only one species is involved. It has, however, been suggested that N. alpina is a natural hybrid between N. procera and N. pumilio and is therefore best kept separate from N. procera, at least for the time being.