Halocarpus bidwillii
Common name
Bog pine
Synonyms
Dacrydium bidwillii Kirk
Family
Podocarpaceae
Flora category
Vascular – Native
Endemic taxon
Yes
Endemic genus
Yes
Endemic family
No
Structural class
Trees & Shrubs - Gymnosperms
NVS code
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
HALBID
Chromosome number
2n = 18
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
Brief description
Much-branched, shrubs or small trees. Foliage distinctly dimorphic (less obvious in adults but usually evident in shaded foliage and on basal branches). Branchlets initially 4-angled, slender (thread-like), leaves bronze-green, yellow-green (often red-tinged). Fruits comprising a dark dark brown, black-brown to dark purple-brown seed sitting within a fleshy, waxy white cup.
Distribution
Endemic. New Zealand: North, South and Stewart Islands from the Central Volcanic Plateau and Kaingaroa Plain south but in the North Island patchy. Records of Halocarpus bidwillii from Te Moehau (Colville, Coromandel Peninsula) are referable to H. biformis.
Habitat
Lowland to subalpine (strictly montane to alpine in the North Island). A shrub or small tree of wetland margins, bogs, poorly draining heathland, frost-flats, river beds and also dry, stony ground and tussock grassland. Halocarpus bidwillii can be locally dominant
Features
Dioecious, spreading or erect, much-branched shrub or small tree up to 4.8 m tall. Trunk 0.3-0.4 m d.b.h, usually multiple, rarely solitary, sometimes spreading. Bark firm, flaking in irregular shards, exposed surface grey, usually covered in lichens, undersides red to red-brown. Branches spreading, bases sometimes layering on contact with soil (in extreme examples give rise to a ring of clonal shrubs surrounding ‘parent’); branchlets initially tetragonous, becoming ± terete with age, 1.2-2.0 mm diameter. Foliage dimorphic; juveniles linear, coriaceous, rigid, apetiolate, spreading,; lamina 5.0-10.0 × 1.0-1·5 mm, bronze green to yellow-green, sometimes tinged red, obtuse to subacute, midvein distinct; adults leaves closely imbricate, coriaceous; lamina 1-2 mm long, obtuse to subacute. Male strobili solitary, terminal and sessile, 2.8-4.6 mm long; apiculus obtuse. Female cones sessile, terminal, each surrounded by leaf-like, elongated bracts (1-5 of which are fertile), and terminating in a central sterile appendage. Carpidia solitary or paired, subterminal, larger than associated bracts. Epimatium adnate to base of carpidium; dorsiventrally compressed and striated, initially green, maturing dark-brown to black with the region around the micropyle swelling to form a fleshy, waxy-white (very rarely yellowish), persistent aril collar at the proximal end of the carpidium; the aril cupular to v-shaped under seed. Seed glabrous, smooth, 3.0-4.5 mm long (including aril), dark brown, black-brown to dark purple-brown, glossy, ovate-oblong, compressed.
Similar taxa
Easily recognised when fruiting by the waxy white (very rarely yellowish) arils subtending the seed. Vegetatively it is distinguished from the other Halocarpus by the smaller much-branched shrub to small tree growth habit, weakly keeled leaves (prominently so in H. biformis), and more slender, initially tetragonous, branchlets. The seeds of Halocarpus bidwillii are distinguished from H. biformis (with which it most often confused) by the ventral and dorsal surfaces usually prominently longitudinally grooved (sometimes only on the ventral surface) (see Webb & Simpson 2001).
Flowering
October - December
Flower colours
No flowers
Fruiting
February - June
Life cycle
Arrilate seeds are dispersed by frugivory (Thorsen et al., 2009).
Propagation technique
Easily grown from seed. Can be struck from semi-hardwood and hardwood cuttings - but often fickle. best grown in an open site in a well drained but moist soil. Dislikes drought and humidity.
Threats
Not Threatened - though uncommon and in decline within some parts of its North Island, eastern and southern South Island range.
Etymology
halocarpus: From the Greek hals ‘sea’, ‘salty’ and karpos ‘fruit’
bidwillii: Named after the botanist - John Carne Bidwill (born 1815 and died 16 March 1853)
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 12 November 2014: Description adapted from Allan (1961), Quinn (1982), Webb & Simpson (2001) and fresh and dried specimens.
References and further reading
Allan, H.H. 1961: Flora of New Zealand. Vol. I. Wellington, Government Printer.
Quinn, C.J. 1982. Taxonomy of Dacrydium Sol. ex Lamb. emend. de Laub. (Podocarpaceae). Australian Journal of Botany 30: 311-320.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309.
Webb, C.J.; Simpson, M.J.A. 2001: Seeds of New Zealand Gymnosperms and Dicotyledons. Christchurch, Manuka Press.
Citation
Please cite as: de Lange, P.J. (Year at time of access): Halocarpus bidwillii Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/halocarpus-bidwillii/ (Date website was queried)