Botanical Report

Botany of Mangemangeroa Reserve, south-east Auckland

Ewen K Cameron & Leslie Haines

 Mangemangeroa Reserve is a 22ha narrow mostly steep coastal forest along the north-west edge of Mangemangeroa Creek and parallel to Somerville Road just south of Howick, south-east Auckland (Fig. 1). The Waitemata sediments are deeply cut down by several small streams flow down the escarpment. Manukau City Council bought the land in 1994 and the pleasant walkway along it was established in 1999. A south Auckland Forest & Bird stalwart, Betty Harris, played a key role in persuading the Mayor and Council to purchase the former private farm. The land on the south-east side of the creek was less steep, and contains less native vegetation. Middens and a fortified site indicate Maori occupation previous to European farming. Farm stock was finally excluded from the forest area in 1999 and some possum control has occurred more recently.

Attendees of the Auckland Botanical Society fieldtrip to Mangemangeroa on 20 May 2006: Sally Barclay (Royal Society Teacher Fellow researching the reserve), Ewen Cameron, Holly Cox (past ecological researcher of the catchment), Gail Donaghy, Graham Falla (Friends of Mangemangeroa Reserve), Colleen Frampton, Leslie Haines, Graeme Jane, Sandra Jones, Joan Kember, Helen Lyons, Elaine Marshall, Carol & Garry McSweeney, Cara and Ros Nicholson (trip leader), Juliet Richmond, Josh Slater and Tony Williams.

In 2000 local Rotary clubs and Forest and Bird, working separately, became involved in bush restoration planting, and the Friends of Mangemangeroa was formed 1-2 years after that (incorporated in 2002) with the aim of fostering the wellbeing of Mangemangeroa with emphasis on protecting the natural features. The Friends come under the umbrella of Manukau Parks and work in consultation with them. In October 2006 a revised draft Management Plan for the reserve was released for public comment.

The author of a recent MSc thesis of the Mangemangeroa catchment, Holly Cox (2000), joined us for the trip. Holly’s thesis was written on the terrestrial ecology, with an emphasis on the large and small scale vegetation patterns, in the Mangemangeroa Catchment. This was undertaken as part of a larger study of how the catchment and protected estuary would be affected by lifestyle block development due to district plan change. She examined: land use and vegetation history and the relationship between the two; current vegetation of the catchment; conservation mechanisms of habitat on private property. The fieldwork undertaken included: permanent plots 15 x 15m; sampling of all vegetation-cover abundance; basal area and density; litter depth, soil compactness; bird counts. The data collected was analysed using classification and ordination. Analysed data was then separated into vegetation types and mapped.

Sally Barclay (2003) also joined us for part of the day. She completed a NZ Science Mathematics and Technology Teacher Fellowship in 2003. She documented the location of the larger trees in the reserve using a GPS and digital photography.

Thomas Cheeseman made notes of his visit ‘Howick to Maungamaungaroa [Mangemangeroa]’ in June 1873 (Stanley 1998) and recorded ‘scanty’ vegetation of Metrosideros robusta, akepiro (Olearia furfuracea), Coprosma lucida, C. robusta, Leucopogon fasciculatus, and Ozothamnus leptophyllus. Two of these (akipiro, Oz. leptophyllus) are not currently recorded for the reserve. Cheeseman recorded at that time on the western side of the creek “…is distinguished with several patches of bush” and on the eastern bank opposite the most common trees were tawa (Beilschmiedia tawa), taraire (B. tarairi), puriri (Vitex lucens), toro (Myrsine salicina) (not currently listed for the reserve), mapou (M. australis), kohekohe (Dysoxylum spectabile) and with a few rimu (Dacrydium cupressinum), kahikatea (Dacrycarpus dacyrdioides) and kauri (Agathis australis).

Alan Esler and one of his sons, Wilson, in December 1984 surveyed the escarpment on the northwestern side of the Mangemangeroa Creek before the reserve was created (Esler & Esler 1985). They briefly described the habitat, vegetation, made several management considerations and provided a vascular plant list of 115 native species. They also interestingly pointed out: “This is the most species-rich forest bordering an estuary in the Waitemata or Manukau Harbours.”

This reserve has some splendid remnants of mature coastal broadleaf forest. The area has been divided into seven vegetation communities: mature kohekohe, taraire forest, mahoe (Melicytus ramiflorus)/kawakawa (Macropiper excelsum)/mapou forest, regenerating totara (Podocarpus totara), taraire/kohekohe forest, mangroves (Avicennia marina), grassland (Fig. 2, Manukau City Council 2006). Although it is a narrow coastal strip of bush, the diversity is from saltmarsh (north end) species such as Plagianthus divaricatus, Samolus repens, Selliera radicans and oioi (Apodasmia similis), to cliff and gully species, with a small number of freshwater wetland (south end) species, including Baumea rubiginosa – others were difficult to distinguish at that time of the year. The mahoe/kawakawa/mapou forest is noticeably youngest and is located toward the narrow north-eastern end of the reserve and also adjacent to the grassed area along Somerville Road. The central bush patches of mature kohekohe forest and the taraire/kohekohe forest have some very large trees such as emergent Metrosideros robusta, and canopy species titoki (Alectryon excelsus), kohekohe, rewarewa (Knightea excelsa), taraire,  tawa, puriri, karaka (Corynocarpus laevigatus), kowhai (Sophora microphylla s.l) and pigeonwood (Hedycarya arborea).  Towards the south-western end of the reserve is the taraire dominated forest with large kahikatea. Clematis paniculata is scattered through the forest. Undergrowth is healthy for the majority of the forest, e.g. mangeao (Litsea calicaris) seedlings, although the area of dense regenerating totara c.8m tall was sparse underneath.

How appropriate to visit an area named after a fern. The reserve and estuary name means ‘valley of the mangemange’ named after the climbing fern Lygodium articulatum, which is very local in the valley (Holly Cox pers. comm.).  It may have been more common before the area was heavily disturbed. It was used by Maori for: rope, thatching (lashing the thatch), fish hooks, eel traps, cutting greenstone and coils to sleep on – the term “bushman’s mattress’ recalls how early Europeans also used it for rough bedding (Riley 1994).

Revegetation is occurring in the small patches within the fenced reserve. Over the last six years there has also been planting (evidently eco-sourced), of mostly Coprosma robusta, manuka (Leptospermum scoparium) and kawakawa, with some taraire, kahikatea, puriri and totara. Some of the planted kawakawa shrubs in the open suffered from a leaf curl – after showing photos and samples to various experts the cause was left unresolved.

Unfortunately there has been some vandalism to vines especially cutting off large rata vines, and it is thought to be possibly due to a misunderstanding of the value of these plants. However, along the protected bush edge adjacent to the grazed pasture is a number of fine specimens of rata: Metrosideros diffusa, M. fulgens, M. perforata and the most special was carmine rata (M. carminea) which was locally common. Most carmine rata were in the open climbing up old ponga trunks intermixed with M. perforata.

Comments on selected native species

Asplenium hookerianum – both forms (A. hookerianum var. hookerianum & var. colensoi) were present at one locality growing together on a shaded trackside bank under the tall coastal broadleaf forest (Fig. 3). Leon Perrie (pers. comm.) says that it is not unusual for the two forms to grow together, although it does appear to be unusual for northern New Zealand (pers. ob.).

Blechnum ?norfolkianum – as noted by Brownsey & Smith-Dodsworth (2000) B. norfolkianum is a poorly defined species which is difficult to tell apart from large mainland forms of B. chambersii and that the two may hybridise. In one forested area on a stream bank by the walkway there were several of these large ferns with sterile fronds to 50cm long x 12.5cm across, with shorter fertile fronds 27 x 6cm (AK 296885).

Streblus heterophyllus hybrid? – occasional wild shrubs (c.1m tall) in the sparse understorey of a dense stand of 8m-tall totara. The lower leaves fiddle-shaped but too large for this species (leaf blade to 7.0cm long x 3.5cm across (Fig. 4, AK 296884)? Perhaps they are hybrids with S. banksii?

Weeds

Esler & Esler (1985) commented that the area contained many alien plants which impair the value of forest reserves and then listed: hawthorn (Crataegus monogyna), brush wattle (Paraserianthes lophantha), blackberry (Rubus fruticosus agg.), tree privet (Ligustrum lucidum), Chinese privet (L. sinense), wild ginger (Hedychium gardnerianum), Himalaya honeysuckle (Leycesteria formosa), moth plant (Araujia sericifera), gorse (Ulex europaeus), pampas (Cortaderia selloana) and woolly nightshade (Solanum mauritianum). These are all still present today, plus many more (see Species List). However, the Friends have made weeds a high profile in the reserve with photos of target species like wandering Jew (Tradescantia fluminensis), woolly nightshade, wattle, moth plant) and collection bags and bins for regular walkers to contribute – this has been partially successful. At the eastern end of the walkway by the estuary several weed species seemed to be localised in this area by what was possibly an old house site marked by two old Morton Bay fig trees (Ficus macrophylla). The weeds here included: Plectranthus ciliatus, Port St John creeper (Podranea ricasoliana) scrambling up through other vegetation to 6m high, a couple of shrubs of Fuchsia boliviana; and on patches of an exotic moss, Fissidens taxifolius, were seedlings of Queensland poplar (Homalanthus populifolius) and loquat (Eriobotrya japonica). If not managed the small patch of Carex divisa observed on the estuary margin has the potential to spread and form extensive swards.

Birds

Birds recorded during our visit: blackbird, Eastern rosella, fantail, grey warbler, harrier, Indian myna, kingfisher, NZ pigeon, silvereye, tui, pukeko, welcome swallow, pied shag, white-faced heron, and Caspian tern.

Conclusions

It was a delight to visit such a treasure hidden away on the side of the estuary. The local residents and Manukau City are to be congratulated in keeping development off this steep land and restoring the bush areas. The walkway is a wonderful asset which gives everyone easy access through the best forested parts and wonderful vistas.

Acknowledgements

Thanks to all on the trip for their comments; Graham Falla and Ros Nicholson for information about the area; and Alan Esler, Trudy McNie and Bec Stanley for assistance in tracking down references.

References

Barclay, S. 2003: The role of Environmental Monitoring in Resource Management. Unpublished Report to?

Brownsey, P.J.; Smith-Dodsworth, J.C. 2000 (2nd ed.): New Zealand ferns and allied plants. David Bateman, Auckland.

Cox, H. 2000: Vegetation and land use of the Mangemangeroa Catchment: the retention of natural values and environmental services. Unpublished MSc thesis, University of Auckland.

Esler, A.E.; Esler, W.R. 1985: Maungamaungaroa Creek, Manukau City – Forest on west bank. Unpublished report to Manukau City.

Manukau City Council 2006: Draft Restoration Plan for Mangemangeroa Reserve. Unpublished, Manukau City.

Riley. M. 1994: Maori healing and herbal. Viking Sevenseas N.Z. Ltd, Paraparaumu.

Stanley, R. 1998: Excerpts from Cheeseman’s Field Notebooks. Auckland Botanical Society Journal 53(2): 70-71.

Stevens, D. 1995: Vegetation Survey of the Mangemangeroa Reserve. Landcare Research report for Manukau City Council.


Vascular plant species list

Key

EE      = records from Esler & Esler (1985) – with names updated

W       = addition from website www.aerolink.co.nz/mangemangeroa (2006)

ABS   = seen by Auckland Botanical Society, May 2006 (* = appears to be a new record)

DC     = additional records from a Landcare Research report (Stevens 1995) – a few unlikely records have been omitted

+       = was already listed on the fieldtrip handout Species List

AK     = herbarium specimens (collected by: RO Gardner, Jan 1981; AE & WR Esler, Dec 1984; RG Falla, Sep 1997; EK Cameron, May 2006)

(A) Native vascular species

Ferns

Adiantum aethiopicum               DS

A. cunninghamii                        EE, DS, ABS

A. diaphanum                           ABS+

A. fulvum                                  EE, ABS

A. hispidulum                            EE, DS, ABS                                          

Arthropteris tenella                    EE, ABS, AK

Asplenium flaccidum                  EE, ABS

A. gracillimum                           ABS*, AK (EE, DS as A. bulbiferum?)

A. hookerianum var. hookerianum          EE, ABS, AK

A. hookerianum var. colensoi     ABS*, AK

A. lamprophyllum                      EE, DS, ABS

A. oblongifolium                        EE, DS, ABS

A. polyodon                              EE, DS, ABS

Blechnum blechnoides               W                                                          

B. chambersii                            EE, ABS

B. filiforme                                EE, DS, ABS

B. fluviatile                                W                                                          

B. membranaceum                    DS, ABS

B. ?norfolkianum                       ABS*, AK

B. novae-zelandiae                   EE, DS, ABS

Cyathea dealbata                      EE, DS, ABS

C. medullaris                            EE, DS, ABS

Deparia petersenii                     ABS+

Dicksonia squarrosa                  DS

Diplazium australe                     DS, ABS

Doodia australis                        EE, DS, ABS

Grammitis billardierei                 DS

Histiopteris incisa                      DS

Hymenophyllum demissum        EE, DS, ABS

Lastreopsis glabella                  EE, DS, ABS

L. hispida                                 DS

L. microsora                             EE, DS, AK

L. velutina                                EE, AK

Leptopteris hymenophylloides    W

Lygodium articulatum                W

Microsorum pustulatum             EE, DS, ABS

M. scandens                             EE, DS, ABS

Paesia scaberula                      DS, ABS

Pellaea rotundifolia                    EE, DS, ABS

Polystichum neozelandicum       EE, DS, ABS, AK

Pneumatopteris pennigera         EE, DS, ABS

Pteridium esculentum                EE, DS, ABS

Pteris macilenta                        EE, ABS

P. tremula                                EE, ABS

Pyrrosia eleagnifolia                  EE, DS, ABS

Rumohra adiantiformis              W

Tmesipteris lanceolata               ABS+

Conifers

Dacrycarpus dacrydioides         EE, DS, ABS

Dacrydium cupressinum            DS

Phyllocladus trichomanoides      DS

Podocarpus totara                    EE, ABS (DS as P. hallii?)                       

Dicotyledons

Alectryon excelsus                    EE, DS, ABS

Apium “white denticles”             EE, DS, ABS*, AK

Aristotelia serrata                      ABS+                                                     

Avicennia marina                      EE, DS, ABS

Beilschmeidia tarairi                  EE, DS, ABS    

B. tawa                                    EE, DS, ABS

Brachyglottis repanda               EE, DS, ABS*

Carmichaelia australis               ABS

Carpodetus serratus                 EE, DS, ABS

Centella uniflora                        ABS*

Clematis paniculata                   ABS*

Coprosma arborea                    EE, DS, ABS         

C. lucida                                   ABS*

C. macrocarpa                          EE, DS, ABS, AK

C. robusta                                EE, DS, ABS

Corynocarpus laevigatus           EE, DS, ABS

Cotula coronopifolia                  DS, ABS

Dysoxylum spectabile                EE, DS, ABS

Elaeocarpus dentatus               EE, DS

Euchiton gymnocephalus           EE

Fuschia excorticata                   EE, DS, ABS

Geniostoma  ligustrifolium          EE, DS, ABS

Haloragis erecta                       EE, ABS

Hebe stricta                              EE

Hedycarya arborea                   EE, DS, ABS

Knightea excelsa                      EE, DS, ABS

Kunzea ericoides                      EE, DS, ABS

Laurelia novae-zelandiae           ABS+

Leptospermum scoparium         DS, ABS

Leucopogon fasciculatus           EE, DS, ABS

Lilaeopsis novae-zelandiae        EE

Litsea calicaris                          EE, DS, ABS

Lobelia anceps                         DS, ABS

Macropiper excelsum                EE, DS, ABS

Melicytus micranthus                 EE

M. ramiflorus                            EE, DS, ABS

Metrosideros carminea              ABS+, AK

Metrosideros diffusa                 ABS*

M. excelsa                                EE, DS, ABS

M. fulgens                                EE, DS, ABS

M. perforata                             EE, DS, ABS

M. robusta                                ABS+

Muehlenbeckia australis            DS, ABS

M. complexa                             EE, DS, ABS

Myrsine australis                       EE, DS, ABS

Nestegis lanceolata                   ABS*

Parsonsia heterophylla              EE, DS, ABS

Persicaria decipiens                  ABS*

Pittosporum crassifolium            ABS

P. tenuifolium                            ABS*

Plagianthus divaricatus              EE, DS, ABS

Pseudopanax crassifolius          EE, DS, ABS

P. lessonii                                 EE, DS

Ranunculus reflexus                  EE, DS

Rubus cissioides                       EE, DS

Samolus repens                        EE, DS, ABS

Sarcocornia quinquefolia           DS

Schefflera digitata                     EE, DS, ABS

Selliera radicans                       EE, DS, ABS

Senecio glomeratus                  DS

S. hispidulus                             DS, EE

S. minimus                               EE, DS

Solanum  americanum               EE, DS, ABS

Sophora chathamica

Sophora microphylla s.lat.         EE, DS, ABS

Streblus ?banksii x S. heterophyllus ABS*, AK

S. heterophyllus                        EE, DS

Vitex lucens                              EE, DS, ABS

Wahlenbergia littoricola             EE, ABS

Monocotyledons

Apodasmia similis                      EE, DS, ABS

Astelia banksii                           EE, DS, ABS

Austrostipa stipoides                 DS

Baumea rubiginosa                   ABS*

Bolboschoenus fluviatilis            EE, DS, ABS

B. medianus                             DS

Carex dissita                            EE, DS, ABS

C. flagellifera                            EE, DS, ABS

C. geminata agg.                      EE, DS, ABS

C. lambertiana                          EE, DS, ABS

C. ochrosaccus                         EE, DS, ABS

C. spinirostris                           EE, ABS

C. virgata                                 EE, DS, ABS

Collospermum hastatum            EE, DS, ABS

Cordyline australis                    EE, DS, ABS

C. australis x C. banksii             EE, DS

Cyperus ustulatus                     EE, DS, ABS

Dianella nigra                            EE, DS

Drymoanthus adversus             ABS*

Earina mucronata                     ABS*

Echinopogon ovatus                  EE

Freycinetia banksii                    EE, DS, ABS

Gahnia lacera                           EE, DS, ABS

Isolepis cernua                         EE, DS, ABS

Juncus edgariae                       EE, DS

J. kraussii                                 EE, DS, ABS

J. pallidus                                 DS

J. planifolius                             EE, DS

J. prismatocarpus                     DS

Libertia ixioides                         EE, AK

Luzula picta var. limosa             DS

Microlaena stipoides                 EE, DS, ABS

Microtis unifolia                         EE

Oplismenus hirtellus                  EE, ABS

Phormium tenax                        EE, DS, ABS

Poa anceps                              EE, DS, ABS

Rhopalostylis sapida                 EE, DS, ABS

Ripogonum scandens                EE, DS, ABS

Rytidosperma biannulare           EE, DS

Triglochin striata                       EE

Uncinia uncinata                       EE, DS, ABS

Zostera muelleri                        EE, ABS, AK

(B) Adventive vascular species

Conifers

Cupressus macrocarpa                DS, ABS

Pinus radiata                               ABS*

 

Dicotyledons

Acacia mearnsii            ABS*

Araujia sericifera          EE, DS, ABS

Aster subulatus            ABS*

Atriplex prostrata          ABS*

Callitriche stagnalis       ABS*

Calystegia sepium x C. sylvaticum EE, ABS*

Centaurium erythraea   ABS*

Cestrum nocturnum      ABS*

Cirsium vulgare            ABS*

Crataegus monogyna   EE, DS, ABS

Conyza sumatrensis     ABS*

Duchesnea indica         ABS*

Eriobotrya japonica       ABS*, AK

Ficus macrophylla (cult.)    ABS*

Fuchsia boliviana          ABS*, AK

Galium aparine             ABS*

Gamochaeta coarctata      ABS*

Geranium homeanum   ABS*, AK

Helminthotheca echioides  ABS*

Homolanthus populifolius   ABS*, AK

Jasminum polyanthum  DS

Leycesteria formosa     EE, DS, ABS

Ligustrum lucidum        EE, DS, ABS

L. sinense                    EE, DS, ABS

Linum bienne               DS

Lythrum hyssopifolia     ABS*

Lotus pedunculatus      DS

Lycopersicon esculentum   ABS*

Mentha pulegium          DS

Myosotis sylvatica             ABS*

Nasturtium microphyllum           EE, DS, AK

N. officinale                              DS, ABS

Paraserianthes lophantha          EE, ABS

Pericallis x hybrida        DS

Physalis peruvianum     ABS*

Phytolacca octandra     DS, ABS

Plantago australis         DS

P. coronopus               DS

Plectranthus ciliatus      DS, ABS, AK

Podranea ricasoliana    ABS*, AK

Prunella vulgaris           ABS*

Ranunculus repens       DS, ABS

Rhus succedanea         ABS*, AK

Rubus fruticosus agg.   EE, DS, ABS

Rumex brownii             DS

R. crispus                    DS, ABS

R. obtusifolius              ABS*

Senecio bipinnatisectus ABS*

S. esleri                       ABS*

S. mikanioides              DS

S. skirrhodon                     ABS*

Silybum marianum        DS

Solanum mauritianum   EE, DS, ABS

S. nigrum                     ABS*

Sonchus oleraceus       DS, ABS

Stachys sylvatica          ABS*, AK

Syzygium smithii           ABS*

Tropaeolum majus        ABS*

Ulex europaeus            EE, DS, ABS

Veronica serpyllifolia     ABS*

Monocots

Asparagus asparagoides   ABS*

A. scandens                 ABS*

Carex divisa                 ABS*, AK

Cortaderia selloana      EE, DS, ABS

Cyperus eragrostis                 DS, ABS

Dactylis glomerata        DS, ABS

Gladiolus undulatus      ABS*

Hedychium gardnerianum  EE, DS, ABS

Holcus lanata               DS, ABS

Juncus acuminatus       DS,

J. articulatus                DS, ABS

J. effusus                                 ABS*

J. gerardii                                 DS

Paspalum vaginatum                 ABS*

Pennisetum clandestinum          ABS*

Schedonorus phoenix   DS, ABS

Tradescantia fluminensis    DS, ABS

Zantedeschia aethiopicum ABS*

Fig. 1. Location of Manngemangeroa Reserve, near Howick.

Fig. 2. Seven vegetation zones of the Mangemangeroa Reserve – from the Restoration Plan (Manukau City 2006).

Fig. 3. Both forms of Asplenium hookerianum: A. hookerianum var. hookerianum & var. colensoi(more finely dissected) growing together on a shaded bank.

Fig. 4. Streblus heterophyllus hybrid? – leaves too large for this species?