A Field Trip to Albany, and Environs, Western Australia
In mid June 1995 I had the pleasure of visiting Albany, on the south coast of Western Australia and travelled as far west as Walpole and as far east as Esperance. On this trip I saw 26 species of carnivorous plant in the wild. The highlights of the trip were seeing Cephalotus follicularis and flowering plants of Utricularia menziesii in the wild and finding Drosera erythrorhiza ssp collina and D. macrantha ssp macranthaoutside their published ranges.
I had the pleasure of seeing the Western Australian pitcher Plant in the wild just east of Albany. A cluster of plants grew on a small south-facing natural bench on the edge of a swamp in an area supporting dense low woodland. At first the plants were hard to find due to the density of the shrubs and understorey of sedges, and they were identified by their large, glossy clusters of non-carnivorous leaves.
Approximately 20 pitcher plants grew in an area 3m by 1m, many in close proximity suggesting that they may be clones on the same root system. Each plant had a sparse rosette of leaves, to 15 cm diameter, consisting of 1 to 5 non-carnivorous leaves and 1 or 2 pitchers. The non-carnivorous leaves were up to 8cm long (including petiole) and to 4.4 cm wide, and were generally held horizontally. One of the non-carnivorous leaves had a bifurcated tip and all had a few small white scale insects on them. The newly produced pitchers were between 5 and 30 mm long, many of which had not yet opened. Most pitchers were covered by the non-carnivorous leaves and a few were partially buried in the thin layer of humus above the peaty sand substrate. Due to the generally low light conditions all but one of the pitchers were fully green in colour; the one exception, on the edge of the colony, had red pigmentation on its unopened lid. The plants had just completed a flush of growth (pitcher formation) and only very immature, indistinguishable new growth was present in the plants growing points.
Dead leaves and pitchers did not persist around the plants and there were no sign of scapes. When Cephalotus is seen growing at the base of tall and dense vegetation it is easy to see how the tall scapes produced by this species, with its strongly fragrant flowers and wind dispersed seeds (Erickson, 1968) is advantageous to promoting cross-pollination of flowers and enhancing seed dispersal. The only plant-animal interactions seen at this site were the slightly chewed edges of some non-carnivorous leaves; some scale insects; a spider web across the entrance of one pitcher; and a detached, torn pitcher possibly due to the travels of a kangaroo. Due to the inconspicuous nature of the pitchers, the way they are often covered by the non-carnivorous leaves, or partially buried in the substrate, and the 1 to 2 m tall overstorey of tangled stems and branches, it appears that the main prey consists of crawling invertebrates. This would change in the first few months after a bush fire has cleared the overstorey when there is much more chance of flying insects also finding their way into the pitchers. Cephalotus follicularis was found growing in the company of Drosera pulchella, D. erythrorhiza ssp collina, and near plants of D. pallida/ erythrogyna and D. erythrorhiza ssp erythrorhiza. The plants grew in well-drained moist peaty sand slightly higher than the adjacent damp soil of a permanent swamp, in well shaded conditions.
Utricularia menziesii was seen near Mt. Manypeaks and at Cape Le Grande National Park growing in small coastal plain swamps and in thin, moss-covered sandy soil on granite outcrops. These gregarious plants were easily seen by their tight cluster of lime-green leaves, to. 1.5 cm diameter. Each plant, or tuber cluster, produced between 2 and approximately 30 leaves. Within populations the size of the leaves often varied between plants; those which produced larger leaves produced fewer than those of other plants of similar tuber cluster size. Between 5 and 10% of plants per colony produced scapes; these were in variable stages of development and varied from those emerging from above the leaves and those with fully opened flowers. Even in the rare case of tuber clusters with more than one scape, these were often in different stages of development. At Cape Le Grande National Park some flower colour intensity was seen. Even though only 2 open flowers were seen here the red pigment intensity of the sepals varied between plants. Most plants had a blood red calyx, held on a green scape, but a small number of plants had a paler red calyx. The open flowers were stunning, and were held on scapes to 3cm tall so that the long spur of the flower was held just above the ground. In the coastal swamp near Mt. Manypeaks one plant was found which had a two flowers on the same scape, although these were several weeks away from opening.
This delightful bladderwort often grew in the company of other carnivorous plants. On granite outcrops it grew with Drosera microphylla, and in the coastal plains it grew with D. tubaestylus, D. menziesii ssp. menziesii and D. pulchella.
A few plants of the tuberous Drosera andersoniana grew on a low granite outcrop north of Hyden. This undulating outcrop was partially buried by a mantle of thin, seasonally damp to saturated, in which this sundew thrived. The vibrant red rosettes grew to 2.5cm diameter, had distinctive rounded lamina, were exposed to full sun and grew amongst Pincushion Grass (Borya sp) and terrestrial orchids. No plants had yet begun to form a stem and no other carnivorous plants were seen at this site.
Red leaved rosettes of the tuberous Drosera browniana grew on, and adjacent to a granite outcrop near Hyden. The leaves grew to 5cm long and were of variable width, 8 to 25 mm maximum width, between plants. Most rosettes were between 4 and 6cm diameter and often grew so thickly that they carpeted the moss and Casuarina leaf covered moist sandy soil in which they grew. Only a few plants had flowered. One plant was found was found with a recently opened the flowers, one of the last of the season, although the white petals were closed when seen. The single pedicelled flowers are pendulous in fruit, then mostly buried by the growing leaves. This species grew near D. macrantha ssp macrantha and D. subhirtella ssp subhirtella.
Drosera bulbosa ssp bulbosa
Golden green rosettes of the tuberous Drosera bulbosa ssp bulbosa were seen at one location, north of Borden, in a shallow gully beside the road on the edge ofMelaleuca woodland. These scattered rosettes were up to 3cm diameter, with up to 10 leaves, each of which had a conspicuously raised midrib. Many plants consisted of 2 to 4 crowded rosettes which had emerged from the same small area and whose leaves and scapes now jostled for space; indicating that daughter tubers had been produced adjacent to the parent tuber. At least 30% of plants seen at this colony had flowered, a few plants still had unopened buds. Three to thirty flowers were produced per rosette, each on its own pedicel, and where daughter rosettes were flowering together these clusters produced up to 70 flowers between them. The only other carnivorous plant species seen at this site was D. subhirtella ssp subhirtella.
Roadside colonies of the pygmy sundew, D. dichrosepala were seen within 20 km east and west of Albany, often discernible by the glowing drops of mucilage backlit by the morning sun. The round red leaved rosettes grew to 1.5 cm diameter, on short stems to 1cm tall, which grew in tight spaced colonies. They grew on dry-surfaced sandy clay soil, which had often been exposed for shallow road cuttings. No sign of spent scapes were seen but this species had developing gemmae, in all stages of development, in the centre of the rosettes seen. This species grew with, or near, D. erythrorhiza ssp erythrorhiza, D. pallida and D. pulchella.
Drosera erythrorhiza ssp erythrorhiza
Colonies of the tuberous Drosera erythrorhiza ssp erythrorhiza were seen in a range of habitats in many areas visited. The rosettes were up to 5cm diameter and consisted of between 2 and 5 leaves round leaves which were green to orange in colour. Due to the abundance of daughter tubers produced on stolons by this subspecies (Lowrie, 1987) when found, this subspecies occurred as close-spaced colonies of up to several hundred rosettes covering up to 3 square metres. At most only 1 to 3 plants in any colony had developing scapes. This species grew in well-drained sandy soil at the Stirling Range and east of Albany; in thin sandy soil on granite outcrops around Albany townsite; in raised areas of peaty soil in sedge swamps near Albany, and in dry-surfaced sandy clay soil and laterite derived soil with a surface cover of iron piesoliths (“pea gravel”) east of Albany. This species was found growing with , or near, Cephalotus follicularis, Drosera dichrosepala, D. erythrorhiza ssp collina, D. hugelii, D. paleacea ssppaleacea, D. pallida and D. pulchella.
Drosera eryrthrorhiza ssp collina
Attractive large rosettes of a tuberous taxa tentatively identified as Drosera erythrorhiza ssp collina were found at the Stirling Range and in Jarah woodland east of Albany. The rosettes, to 10 cm diameter, had 6 to 10 ovate leaves, which commonly had a red tinged edge. This subspecies often grew with D. erythrorhiza ssp erythrohiza and occurred as small colonies of relatively widely spaced rosettes; however, some asexual reproduction did occur in which the daughter tuber was produced immediately beside the parent tuber. Only a few plants in a few colonies had developing scapes. This subspecies was found mainly in open woodland, in moist well-drained sandy soil, in the company of Cephalotus follicularis, D. erythrorhiza ssp erythrorhiza, D. hugelii, D. pallida/ D. erythrogyna, and D. pulchella and less commonly, in moist sandy-clay soil in more open conditions, in the company of D. hugelii and D. pulchella. The occurrence of this form on this field trip is a modest range extension of its published range (Lowrie, 1987).
Golden green rosettes of the winter-growing annual Drosera glanduligera were found at only one location. Approximately 100 km east of Southern Cross. Plants grew in sodden, to saturated, thin, coarse-grained sandy soil on, and adjacent to, granite outcrops in generally unshaded positions. The rosettes grew to 3cm diameter and had not yet begun to produce scapes. This species grew with D. andersoniana and D. subhirtella ssp moorei.
I was able to see for myself the incredibly rapid speed at which the outer, longest stalked retentive glands are able to move simply by placing my finger on a few leaves. This had been reported to me by I.. Snyder and F. Rivadavia (pers. comm., 1995) and is poorly known characteristic of this delightful species.
Two forms of the erect, bell-shaped leaves of the tuberous Drosera hugeliiwere on my trip. The most widespread form was a robust, generally golden green form which grew to 50 cm tall, and was seen on lower elevations of the Stirling Range and in a sedge swamp near Albany, some if which were in scape. A colony of attractive, strongly red pigmented plants, to 10 cm tall, was seen on the summit plateau of Bluff Knoll in the Stirling Range, growing to within 100m of the summit. This “alpine form” is a good candidate for subspecies status (P. Mann, pers. comm., 1995). This species grew with, or near, D. eryrthrorhiza ssp erythrorhiza, D. pallida/D. erythrorgyna, D. pulchellaand D. roseana. The alpine subspecies grew with D. stolonifera ssp monticola.
Drosera macrantha ssp macrantha
Robust climbing or scrambling plants of the tuberous Drosera macrantha sspmacrantha, to 80 cm tall, were seen in many of the eastern and inland areas visited. The generally golden green plants, with concave lamina held in alternate whorls of three, and with short stalked retentive glands over the upper half of the stem, were seen in a number of habits; in open woodland near a granite outcrop at Hyden; in well-drained sandy soil at the Stirling range; in well-drained laterite-derived soil west of Ravensthorpe; in thin sandy soil on a granite outcrop at Cape Le Grande; and in thin sandy soil around a granite outcrop 150 km north of Kalgoorlie. The latter represents a significant range extension of this species. In most cases the plant were just starting to produce flower buds. This species was found growing with, or near D. erythrorhiza ssperythrorhiza, D. browniana, D. subhirtella ssp subhirtella and D. zonaria.
Vibrant red erect plants of the tuberous Drosera microphylla, to 15 cm tall, were found growing in abundance on the northern flanks of Mt. Cape Le Grande. The plants grew in thin, sopping, moss-covered sandy soil with pincushion plant (Borya sp.) and Utricularia menziesii. Plants had not yet begun to develop scapes but from a previous visit to this site the plants are known to be white petalled (Gibson, 1992).
Drosera menziesii ssp menziesii
Erect, red, non-flowering plants of the tuberous Drosera menziesii sspmenziesii, to 30 cm tall were seen at two locations visited. One was a granite outcrop in Karri forest east of Denmark where the plants grew in abundance in thin, moss-covered soil. The other site was a near Mt. Manypeaks where a single plant grew in moist sandy peat at the edge of a small swamp. At the second site the plant grew near U. menziesii, D. pulchella, D. scorpiodes and D. tubaestylus.
A few colonies of golden green tuberous Drosera modesta were found in a range of locations on the south coast. This species often grew in shaded conditions, in well-drained, moist sandy soil on the floor of tall Eucalyptus-dominated woodland. Plants were in many stages of development, from rosettes to 1.5 cm diameter, to scrambling plants to 30 cm tall. The alternate, triangular leaves, with two prominent projections, and common formation of daughter tubers at the end of inclined stolons were key features in identifying this species. This sundew often grew apart from other carnivorous plants but at one location, just east of Albany, it grew near D. pallida.
Drosera neesii ssp neesii
A few scattered plants of Drosera neesii ssp neesii were seen at two sites near Albany in early December. The plants, to 40 cm tall, were just starting to go dormant, but the large, lime green shield shaped leaves and tips of the bright yellow petals on the dead flowers were clearly visible. The plants grew in moist peaty sand in either open woodland, near the Cephalotus site, or grew in more open low woodland which had been recently burnt. This species grew in marginally more elevated ground then Drosera pulchella at both sites visited. It also grew near Cephalotus and Drosera occidentalis ssp australis at the site.
Drosera occidentalis ssp australis
Only a few plants of this diminutive pygmy sundew, D. occidentalis sspaustralis, were seen on the expedition, and these were at Cape Le Grande. The vibrant red rosettes, to 8 mm diameter, grew in moist peaty soil, with a variable concentration of clay and sand, at the margin of swamps and lakes.
Erickson, R. 1968. Plants of Prey In Australia. UWAP
Gibson, R. 1992. Carnivorous Plants of the Esperance District, Western Australia. Bulletin of the Australian Carnivorous Plant Society, Inc.
Lowrie, A. 1987. Carnivorous Plants of Australia: Volume 1, UWAP.
Lowrie, A. 1987. Carnivorous Plants of Australia: Volume 2, UWAP.
I wish to thank Todd, Lynda and Brian for providing access to the Cephalotussite, and Phill Mann for providing details of some excellent plant locations.