Carbeen Open Forest community in the Darling Riverine Plains and Brigalow Belt South Bioregions - Determination to make a minor amendment to Part 3 of Schedule 1 of the Threatened Species Conservation Act

NSW Scientific Committee

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Determination to make a minor amendment to Part 3 of Schedule 1 (Endangered ecological communities) of the Act by inserting the Carbeen Open Forest community in the Darling Riverine Plains and Brigalow Belt South Bioregions (as described in the determination of the Scientific Committee under Division 5 Part 2) and as a consequence to omit reference to the Carbeen Open Forest community in the Darling Riverine Plains and Brigalow Belt South Bioregions (as described in the final determination to list the ecological community) which was published on pages 10313 to 10316 in the NSW Government Gazette No. 124 dated 29 October 1999. Minor amendments to the Schedules are provided for by Division 5 of Part 2 of the Act.

 

The Scientific Committee is of the opinion that the amendment is necessary or desirable to correct minor errors or omissions in the Determination in relation to the Thackway and Cresswell (1995) reference.

 

The Scientific Committee has found that:

 

1. Carbeen Open Forest is the name given to the plant community that is characterised by the following assemblage of species:

 

Abutilon oxycarpum

Acacia excelsa

Acacia salicina

Alectryon oleifolius

Allocasuarina luehmannii

Alstonia constricta

Aristida calycina

Atalaya hemiglauca

Austrostipa scabra ssp scabra

Callitris glaucophylla

Capparis mitchellii

Casuarina cristata

Chloris truncata

Corymbia dolichocarpa

Corymbia tessellaris

Crinum flaccidum

Cymbidium canaliculatum

Einadia nutans

Eremophila mitchellii

Eucalyptus camaldulensis

Eucalyptus populnea

Geijera parviflora

Panicum decompositum

Petalostigma pubescens

Rhagodia spinescens

Sclerolaena birchii

 

2. The total species list of the community is larger than that given above, with many species present only in one or two sites or in very small quantity. In any particular site not all of the assemblage listed may be present at any one time (at least above ground), seeds of more species may be present in the soil seed bank. The species composition of a site will be influenced by the size of the site and by its recent disturbance history. For a number of years after a major disturbance, dominance by a few species may occur, with gradual restoration of a more complex composition and vegetation structure over time. The balance between species will change over the fire cycle, and may also change in response to changes in fire frequency.

 

3. Carbeen Open Forest occurs on siliceous sands, earthy sands and clayey sands and is a distinctive plant community on the riverine plains of the Meehi, Gwydir, MacIntyre and Barwon Rivers and has been recorded from the Local Government Areas of Moree Plains and Walgett within the Darling Riverine Plains and Brigalow Belt South Bioregions. Bioregions are defined in Thackway and Cresswell (1995).

 

4. The structure of the community was originally open-forest but may now exist as woodland or as remnant trees.

 

5. Characteristic tree species are Corymbia tessellaris and Callitris glaucophylla, associated trees include Corymbia dolichocarpa, Eucalyptus populnea, Eucalyptus camaldulensis, Casuarina cristata and Allocasuarina leuhmannii.

 

6. The community is restricted in the landscape by edaphic factors. Adjacent communities - either other woodland communities or grasslands on heavy clay soils are distinct. Corymbia tessellaris (carbeen) and Callitris glaucophylla (white cypress pine) are restricted to well drained sandy soils.

 

7. Carbeen Open Forest has been cleared for grazing and cropping , and is further threatened by clearing for agriculture, grazing, fire management practises, and land-forming for irrigated crops. Remaining stands of this community are typically fragmented and often isolated. Remnants are also threatened by weed invasion especially by Cenchrus species, Opuntia aurantiaca, Opuntia stricta, and Lycium ferrocissimum.

 

8. Less than 500 ha of the Carbeen Open Forest Community is found within Boomi, Boomi West and Boronga Nature Reserves.

 

9. In view of the small size of existing remnants, the threat of further clearing and other known threats (listed in 7), the Scientific Committee is of the opinion that the Carbeen Open Forest in the Darling Riverine Plains and Brigalow Belt South Bioregions is likely to become extinct in nature in New South Wales unless the circumstances and factors threatening its survival or evolutionary development cease to operate.

 

 

Dr Richard Major

Chairperson

Scientific Committee

 

Proposed Gazettal date: 02/12/11

Exhibition period: 02/12/11 – 03/02/12

 

Reference:

 

Thackway R, Cresswell ID (1995) An interim biogeographic regionalisation for Australia: a framework for setting priorities in the National Reserves System Cooperative Program. (Version 4.0. Australian Nature Conservation Agency: Canberra.)

Page last updated: 02 December 2011