Corchorus cunninghamii - Department of Environment and Climate ...

Draft Recovery Plan Corchorus cunninghamii
Both NSW populations of Corchorus
cunninghamii occur on basalt-derived soils.
The Toonumbar population occurs on dark
brown or chocolate soils characterised by a
friable, porous surface horizon with scattered
basalt stones, a clay subsoil and are slightly
acidic. The population at Bungabbee is on a
similar soil type formed from basaltic colluvium
overlying sedimentary rocks.
The Queensland populations occur on
metasedimentary geology (Halford 1993). The
red-yellow podzolic soils formed on
metasediments differ significantly from the
NSW basaltic soils, tending to be more acidic,
shallower and stony. Metasediments are
widespread in the Brunswick and Tweed Valleys
on the eastern side of the Mt Warning shield in
NSW, yet there are no records of Corchorus
cunninghamii from this area.
The general climatic regime of the Richmond
Valley is humid and subtropical. Corchorus
cunninghamii occurs in areas with an average
annual rainfall of 1,200–1,400 millimetres,
which is typical of much of the upper Richmond
River Valley and significantly drier than areas
near the coast (Bureau of Meteorology 1972).
The relatively narrow, lower rainfall band
preferred by C. cunninghamii may account for
its absence from metasediments in the
Brunswick and Tweed Valleys, where minimum
average annual rainfall is about 1,700
millimetres.
Sites within the Toonumbar Hoop Pine
plantation occur along old snig tracks and log
dumps in the ecotone between the open forest
and the planted Hoop Pine. The natural
vegetation of this area appears to have been dry
rainforest but was cleared for plantation in the
1940s and Corchorus cunninghamii may have
been present in the original vegetation or the
soil seed bank.
Species occurring with Corchorus
cunninghamii at specific locations are listed in
Table 1. Common canopy species occurring in
the open forest side of the ecotone are Grey
Gum (Eucalyptus propinqua), Grey ironbark
(E. siderophloia), Tallowwood (E. microcorys)
and Brush Box (Lophostemon confertus).
Typical canopy species on the rainforest side of
the ecotone include Hoop Pine, Australian Teak
(Flindersia australis), Native Elm (Aphananthe
philippinensis), Ribbonwood (Euroschinus
falcata), Grey Ebony (Diospyros pentamera),
Lacebark (Brachychiton discolor) and Morton
Bay Fig (Ficus macrophylla).
Table 1. Vegetation characteristics at Corchorus cunninghamii locations in NSW and
Queensland
Location General
Description
Toonumbar National
Park, NSW
Bungabbee Nature
Reserve, NSW
Toonumbar State Forest,
NSW
Wongawallen, south of
Beenleigh, Queensland.
Ormeau, south of
Beenleigh, Queensland
Note:
* introduced species
tall wet sclerophyll
forest - dry
rainforest ecotone
tall wet sclerophyll
forest - dry
rainforest ecotone
Hoop Pine
plantation
Common Species
Lophostemon confertus, Eucalyptus siderophloia,
Neolitsea australiensis, Alectryon subscinereus,
Croton verrauxii, *Lantana camara, Cordyline
petiolaris, Doodia aspera, Cyperus enervis,
*Ageratina adenophorum, *A. riparia
Lophostemon confertus, Araucaria cunninghamii,
Endiandra pubens, Mallotus philippensis,
Cryptocarya microneura, Croton verrauxii,
Alpinia caerulea, *Lantana camara, Doodia
aspera, Cyperus enervis, Adiantum formosum
Araucaria cunninghamii, *Lantana camara,
*Ageratina adenophora
open forest Eucalyptus propinqua, E. microcorys,
Lophostemon confertus, Rhodamnia rubescens,
Omalanthus populifolius, Melia azedarach,
Abutilon oxycarpum, Solanum stelligerum,
*Lantana camara, Derris involuta, Smilax
australis
open forest Eucalyptus propinqua, E. siderophloia, E.
intermedia, Lophostemon confertus, Polyscias
elegans, Psychotria daphnoides, Alphitonia
excelsa, *Lantana camara, Derris involuta
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