Flora of New Zealand Series

D. recurvatum W. R. B. Oliver in T.N.Z.I. 59, 1929, 712, t. 23 non Col. in T.N.Z.I. 21, 1889, 93.

Type locality: Little Barrier Id. Type: W, W. R. B. Oliver, 8/10/1928.

Rather slender tree up to c. 10 m. tall with smooth dark grey bark; branches slender, bark brown. Lvs thick, coriac., densely clustered towards tips of branchlets; sheath ± 5 × 4 cm., gradually tapering into lamina ± 5-6 dm. × 2.5-3 cm.; margins smooth or nearly so, apex acuminate. Panicle very stout, terminal, erect, ± conical, 20-30 × 10 cm.; branches stout, at wide angle to axis, again several times branched, branchlets up to ± 3 cm. long. Fls? Capsule ± 2 mm. diam., depressed-globose, shortly pedicelled to sessile, invested by persistent broadly ovate-oblong ciliate sepals c. 1·5 mm. long.

DIST.: N. Forest and shrubland from c. lat. 36º 30' to 38º.

HYBRIDISM

Field evidence abundantly supports the view that hybrids occur freely between several members of the subgenus Oreothamnus, but no experimental work has been done and little is known about the fertility of the hybrids. On certain boggy mountain areas (e.g. Mount Maungatua, Blue Mountains) there is a very complicated assemblage of forms. Oliver (loc. cit. 1929) has named a number of hybrids, remarking (p. 682) that "it must be remembered that a series of hybrids between any two species may include forms grading into both parents." Cockayne and Allan (Ann. Bot., Lond. 48, 1934, 36) record the following groups: D. longifolium × politum ("we think that into this group comes D. Pearsoni Kirk"); × prostratum; × recurvum (× D. varium W. R. B. Oliver, loc. cit. 700); × scoparium (× D. insulare W. R. B. Oliver, loc. cit. 703). D. uniflorum × kirkii; × prostratum (× D. erectum W. R. B. Oliver, loc. cit. 688). D. filifolium × recurvum (× D. arcuatum W. R. B. Oliver, loc. cit. 701); × subulatum (× D. vulcanicum W. R. B. Oliver, loc. cit. 697). D. lessonianum × sinclairii (× D. densiflorum W. R. B. Oliver, loc. cit. 699); × subulatum (× D. marginatum W. R. B. Oliver, loc. cit. 697). D. kirkii × pronum (× D. saxicolum W. R. B. Oliver, loc. cit 688). Cockayne and Allan (loc. cit.) also record longifolium × traversii -the only known cross between members of the two sub-genera. Good examples may be seen on Arthur Pass. Oliver's view that D. varium Col. in T. N. Z. I. 28, 1896, 603 and D. urvilleanum var. montanum Cheesem.  Man. N.Z. Fl. 1906, 424 are based on hybrids between longifolium and recurvum appears fully justified.