Tone (1968) lit: 83-92 83

A FURTHER EXAMINATION OF THE PERMANENT QUADRATS ON LITTLE BARRIER ISLAND

By Barbara S. Parris* and Lynn R. Keen. *

INTRODUCTION

In 1951*1 in order to study the quantitative changes in the vegetation on a long term basis, two permanent quadrats were established on Little Barrier Island in regenerating Leptospermum which has been undisturbed since the turn of the century. Both quadrats are situated on the ridge running up behind the caretaker's house, and are accessible from the Thumb track. Pipes indicating the location of the quadrats are by the side of the track. Quadrat I is just above the 'Moss Clearing1, at an altitude of approximately 200', as noted from the altitude marker tags attached to the trees at intervals of 100' (vertical) up this track. Quadrat II is at an altitude of approximately 600'. For a full descri• ption of the location of the quadrats see Bellingham & Percy (195*0.

Since their establishment the quadrats have been examined twice before, in 1958 and 1963.

SAMPLING METHODS

English & Brock's (1963) method of sampling, has been used. The vegetation is divided as follows: - 1. Poles : Between k and 12 inches D. B. H. (diameter breast height) 2. Saplings: Between 1 and h inches D. B. H. which are further subdivided into (A) 1 - 2 inches D. B. H. (B) 2-3 inches D. B. H. (C) 3 - k inches D. B. H.

^Department of Botany, University of Auckland. TABLE I. SPECIES FOUND IN QUADRAT I ARRANGED IN ORDER OF DENSITY

DENSITY FREQUENCY SAPLINGS STRIPLING 1954 1963 1967 1954 1963 1967 POLES A 3 C a b c

1963 3 41 31 11 Myrsine austral is 1. 23 0. 37 0. 71 100 100 96 - - - 1967 5 19 33 1963 15 1 — 2 3 2 Coprosma aroorea 0. 29 0. 24 0. 23 64 63 60 1967 14 4 4 1 1963 • 11 2 Melicytus rail:; crjs 0. 13 0. 13 0. 13 32 40 36 1967 - - - a 5 - 1963 12 Leptospermum ericoides 0. 15 0. 12 0. 12 48 44 44 1967 12 _ _ _ _ _

1963 • 3 2 3 5 3 Pittosporj-3 unoeila^un 0. 17 0. 16 0. 11 40 36 28 1967 2 1 m 1 m. 2 1963 1 — 11 i • Coprosma rhamnoides 0. 30 0. 20 0. 10 56 40 28 1967 - - 9 I 1963 Pittosporum tenuifolium 0. 04 X* 0. 02 12 X 8 1967 - 1 - - - i - 1963 • 1 Gymnelaea lanceolata O. Oi 0. 01 0. 01 4 4 4 1967 - - 1 - 1963 — : : Pseudopanax crassifolium 0. 01 0. 01 0. 01 4 4 4 - - 1967 - - i - 1963 1 Dy5oxylj-i spectacle 0. 01 0. 01 0. 01 4 4 4 1967 - - - 1 - - 1963 :* Coprosma spatnulata X 0. 07 0. 01 X 24 4 1967 1 - - 1963 : : 3 Olearia furfuracea 0. 04 0. 03 X 12 12 X 1967 — _ 1963 ~ ~ : :• Cyatnea Dealbata 0. 01 0. 01 X 4 4 X • 1967 - 1963 6. 9 12. 4 1. 6 0. 0 45. 7 24. 3 9. 0 Numbers in each class as a percentage of the total number 1967 3. 22 15. 07 0. 68 0. 0 30. 14 37. 67 3. 22 • X = "not recorded" 85

3. Striplings: Less than 1 inch D. B. H. and higher than 12 inches. These are further subdivided into height classes (a) 1 - 5 feet (b) 5-10 feet (c) 10 - 15 feet (d) 15 - 20 feet 1+. Ground cover: Phanerogams and cryptogams less than 12 inches in height. Frequen• cy and density of in this category are not recorded because of their erratic occurrence. Each quadrat is divided into 6 foot square plots which are sampled separately as above. Divisions were made with strings and difficulty in keeping these taut may have led to the differences in fre• quency for some species compared to previous work where the numbers of plants have remained the same (see Tables).

The results are expressed as frequency and den• sity as in 195*+, and 1963, with the various height and D. B. H. classes also recorded, as in 1963.

Frequency and density were calculated as follows: P _ Quadrats in which species occurs ^ Total no. of quadrats _ Total no. of individuals of a given species Total area of the plot (in square yards). Heights were measured with an Abney level.

Lycopods, , Gymnosperms and Dicotyledons are as in 'Flora of New Zealand', by H. H. Allan (1961) and Monocotyledons are as in 'New Zealand Flora', by T. F. Cheeseman (1925).

QUADRAT I. Canopy heights determined: 195*+ 27 - 33 feet 1958 30 - 35 feet 1963 1+0 - 1+5 feet 1967 32 - 36 feet TABLE II. SPECI E S D IN QUADRA T I I A R R D IN 0 R D E N S I

DENSITY FREQUENCY SAPLINGS STRIPLINGS 1954 1963 1967 1954 1963 1967 POLES A B C a b c 1963 3 62 7 2 Neopanax arboreum 0. 30 0. 36 0. 44 43 46 42 1967 - 3 - - 74 3 2 1963 0. 16 X» 0. 40 38 X 66 1967 - - - 70 9 1963 2 1 : 13 : Pittosporum tenuifolium 0. 06 0. 055 0. 19 22 24 33 • 1967 2 i 34 - - 1963 15 3 3 ~ 2 Leptospermum ericoides 0. 25 0. 18 0. 18 64 56 52 1967 17 i 10 6 2 1963 26 1 Myrsine australis 0. 09 0. 145 0. 165 23 38 34 _ 1967 - - 31 1 - 1963 20 3 Olearia furfuracea 0. 15 0. 11 0. 16 30 24 26 1967 - - - - 26 4 i 1963 35 3 Alseuosmia macrophylla 0. 03 0. 19 0. 155 26 40 34 1967 - - - - 27 4 - 1963 30 1 i Coprosma rhamnoides 0. 10 0. 155 0. 15 24 36 36 1967 - - - - 29 1 1963 2 2 1 i Olearia rani 0. 15 0. 15 0. 14 43 44 34 1967 - 2 - 16 9 i 1963 7 4 1 57 11 Coprosma arborea 0. 15 0. 40 0. 12 44 70 40 1967 - 7 4 1 7 5 - 1963 1 1 2 6 5 i Pittosoorurc umbellatum 0. 13 0. 03 0. 10 36 20 23 1967 - 3 2 9 4 2 1963 Cyathea dealbata 0. 23 X 0. 09 53 X 22 1967 - - - - 16 1 - 1963 2 3 1 1 17 1 Agathis australis 0. 08 0. 12 0. 08 30 30 22 1967 2 1 1 2 9 1 - 1963 — 1 11 Cyathodes fasciculatus 0. 08 0. 07 0. 06 23 26 20 • • 1967 — 10 2 • X = "not recorded* continued TABLE II. Continued

DENSITY FREQUENCY SAPLINGS STRIPLINGS 1954 1963 1967 1954 1963 1967 POLES A B C a b c 1963 5 6 Senecio kirkii 0. 06 0. 055 0. 055 16 16 16 1967 - - - - 6 4 1 1963 — 4 Geniostoma liqustrifolium 0. 05 0. 02 0. 045 16 8 13 _ 1967 - 8 1 - 1963 1 2 1 Gymnelaea lanceolata 0. 01 0. 023 0. 035 2 10 14 1967 1 3 2 1 - - - 1963 1 2 1 Knightia excelsa 0. 06 0. 03 0. 03 X» 10 8 • i 1967 1 2 - 1 2 - 1963 — — 2 1 — Nothofagus truncata 0. 02 0. 015 0. 015 6 6 8 1967 3 1 1963 — : 2 Beilschmiedia tawa 0. 01 0. 015 0. 015 2 4 4 — 1 1967 - - 2 1 - 1963 — 2 1 Pseudopanax discolor 0. 005 0. 015 0. 015 2 6 4 1967 - - - 2 1 - 1963 2 2 1 Gymnelaea cunninghamii 0. 005 0. 036 0. 015 2 12 6 1 1967 1 2 1963 m :i Coprosma lucida 0. 01 0. 005 0. 005 2 2 2 1967 - 1 - 1963 — i Corokia buddleoides 0. 005 0. 005 0. 005 2 2 2 1967 i - - 1963 :— : 1 Pseudopanax crassifolium 0. 02 0. 005 X 4 2 X - - 1967 : : - Cyathea medullaris 0. 03 X X 10 X X 1963 ------the number 4. 5 6. 5 5. 0 3. 0 55. -5 11. 1 r. 6 Numbers In each class as a percentage of total 4 1967 3. 96 . 72 4. 34 2. 08 71. 83 11. 70 1. 32 * X » "not recorded" 88

In view of the age of the canopy, which is all Leptospermum about TO years old, and its obvious mat• urity, it seems more reasonable to accept a height increase of 1 - 2 feet in nine years than the 10 feet increase in five years put forward by English and Brock and necessitating a spurt of growth out of character with the previous recorded height increases. Notable is the lk% increase in class b striplings and similar decrease in class a striplings over the k year period. This change in importance was not noted in quadrat 2.

Myrsine australis is still the most abundant species in the quadrat.

Seedlings are sparse in the ground cover. Those of the following species were found: Neopanax arboreum, Melicytus ramiflorus, Myrsine australis, Dysoxylum spectabile, Pittosporum tenuifolium, P. umbellatum, Coprosma spp., Olearia furfuracea and Cyathea dealbata, i. e. with the exception of Leptospermum ericoides, Gymnelaea lanceolata and Pseudopanax crassifolium, all tree and shrub species are present as seedlings. Olearia furfuracea and Cyathea dealbata, although present as seedlings and recorded as being present in 195*+, 1958 and 1963, were not found in 196T.

Neopanax arboreum, Dysoxylum spectabile and Olearia furfuracea have not previously been recorded as seedlings in this quadrat.

The ground cover is predominantly of med• ia. Adiantum hispidulum, Asplenium lucidum and Phymatodes diver si folium are less common but still important in the ground cover. Gahnia lacera, Uncinia australis, Parsonsia heterophylla, Clematis paniculata and Oplismenus undulatifolius are also present. Parsonsia was recorded in 1958 and not in 1963, while Clematis and Oplismenus have not been recorded in this quadrat before.

Percy (1958) predicted that Phymatodes diversi- 89 folium and Asplenium lucidum would increase at the expense of Doodia, but this does not appear to have taken place to any great extent. On other sites along the Thumb track in comparable areas Oplismenus appears to compete more with Doodia than do Asplen• ium or Phymatodes. At present there is only one small of this grass in Quadrat I, but its spread and possible competition with Doodia should be noted.

No epiphytes were noted in this quadrat.

A specimen of Podocarpus spicatus, identified as P. ferrugineus by Bellingham & Percy (1958) near the southern side of the quadrat, is atypical of the vegetation of this part of the ridge. Near it is a juvenile of the same species, not far from the quad• rat boundary. It will be interesting to see if this species in time establishes itself within the quadrat.

QUADRAT II. Canopy heights determined: 195*+ 25 - 30 feet 1958 29 - 3b feet 1963 37 - feet 1967 37 - k2 feet and lower at 28 - 36 feet

Leptospermum is again the dominant canopy tree. There appear to be two distinct canopies of this species. The changes in the canopy since 195^ are summarised below. 195^ 1967 Emergent Agathis australis 1 2 In canopy Agathis australis 3 2 Pittosporum tenuifolium k 1 P. umbellatum 2 1 Neopanax arboreum 2 Coprosma arborea 1 90

Pseudopanax crassifolium 1 Almost at canopy Gymnelaea cunninghamii 1 3 Pittosporum tenuifolium - 3 P. umbellatum - 1 Coprosma arborea - 1

Overtopping of Pittosporum tenuifolium, P. umbellatum and Coprosma arborea was noted in 1958 and 1963. The second Agathis has emerged from the canopy since 1963.

The two specimens of Neopanax arboreum and the one of Pseudopanax crassifolium noted in 195*+ and 1958 were not seen in 1967.

Since 195*+ the diameter of the largest Agathis has increased from 15 inches to l6 inches.

Seedlings are more abundant here than in Quadrat I. Again, nearly all the tree and shrub species in the quadrat were represented, with the notable excep• tion of Leptospermum. A new shrub species, Cyathodes juniperina(l) was noted. The specimen of Gymnelaea montana (perhaps G. cunninghamii or G. lanceolata) noted by English & Brock as a seedling in 19&3 can have made very little growth. If it is the same plant, it has not grown to 12 inches in height in four years.

Doodia media is absent from this quadrat.

Species apart from seedlings in the ground cover are Lygodium articulatum, Lindsaea trichomanoides, Grammitis ciliata, Phymatodes diversifolium, Cyathea dealbata, Asplenium flaccidum, A. lucidum, A. falcat- um, capense, Lycopodium volubile, Clematis paniculata, , Carex inversa, Gahnia setifolia, Uncinia australis, Astelia trin- ervia, A. solanderi (A. cunninghamii), Collospermum hastatum, Acianthus fornicatus, Pterostylis trullifolia, Pterostylis montana rubicola. Of these, Grammitis 91

ciliata, Asplenium falcatum, Acianthus fornicatus, Pterostylis trullifolia, Pterostylis montana rubicola and Clematis paniculata have not been recorded in the quadrat before.

No epiphytes have been recorded before. The following species were found epiphytic, chiefly on Gymnelaea, occasionally on Leptospermum: Mecodium sanguinolentum, M. dilatatum, Cardiomanes reniforme, Grammitis ciliata, Ctenopteris heterophylla, Bulbo- phyllum pygmaeum. None of these is abundant. The number and variety of epiphytes will probably increase as the vegetation becomes more dense and offers more resistance to the desiccating effect of wind.

CONCLUSIONS

Since the last examination there have been no great changes in the vegetation of the quadrats except the occurrence of six species of epiphytes in Quadrat II.

Quadrat I is homogeneous and static, while Quadrat II has a more diverse flora.

Further sampling is required to establish possible trends towards the establishment of differ• ent vegetation types in the two quadrats; perhaps a coastal forest type in Quadrat I, and a kauri - beech type in Quadrat II.

ACKNOWLEDGEMENTS

The authors wish to thank Mr. R. E. Beever for identifying the Pterostylis species in Quadrat II.

REFERENCES

Bellingham, N. O. & C. A. Percy. 195b. Permanent Vegetation Quadrats in Leptospermum Communities of Little Barrier Island. Tane 6, 110-115- 92

English, D. A. & J. L. Brock. 196U. A Further Examin• ation of the Permanent Quadrats on Little Barrier Island. Tane 10, 79-83.

Percy, C. A. 1958. Examination of the Permanent Quadrats on Little Barrier Island. Tane 8, 106-109.