|
Rattans and Rheophytes -- Palms of the Mubi River
Reprinted
with permission from the July 1997 issue of Principes, Vol 41,
No 3
Journal of the International Palm Society (Renamed as Palms in
1999)
©
1997 The International Palm Society, all rights reserved
WILLIAM
J. BAKER
 Department of Botany,
Plant Science Laboratories, University of Reading, Whiteknights, P.O. Box
221, Reading, Berkshire, RG6 6AS, United Kingdom.
The island of New Guinea
holds some of the greatest botanical mysteries left on earth. It is a place
where vast tracts of rain forest still stand in an unexplored and impenetrable
landscape, where Asia meets Australia in a melting pot of fantastic biological
diversity. Although this uncharted paradise seems somewhat distant now,
with the help of my field notes and, no doubt, a little imagination, I shall
attempt to tell a few tales of my first field-trip to collect palms in New
Guinea.
As is the case for many
plant groups in New Guinea, the palms of the island are very poorly known.
This is a result of the severe lack of botanical collections from the region,
principally due to the inaccessibility of most parts of the island, coupled
with the old bugbear that general collectors do not like making specimens
of bulky plants such as palms. Enough said! Although there have been several
specialist palm collectors active in New Guinea, there is still a dearth
of material in herbaria. Thankfully, a number of palm botanists are taking
a strong interest in the palms of New Guinea and the situation should change.
Recently, I was fortunate enough to be asked to spend two months studying
rattan diversity in Papua New Guinea (PNG), the eastern half of the island,
as part of a larger rattan project at the Royal Botanic Gardens, Kew funded
by the European Union. Naturally, I was more than happy to oblige and consequently
spent January and February 1996 indulging in some of the most exciting plant
exploration that I have experienced so far.
I do not intend to give
every detail of the trip, but rather an account of some particularly excellent
collecting that I enjoyed while I was a guest of the Worldwide Fund for
Nature (WWF) project in the Kikori basin. As part of the packed program
very kindly organized for me by Tanya Leary of WWF, it was arranged that
I should spend three days based at Kantobo in the Southern Highlands where
I would collect around the Mubi river. Having already spent a week being
flown around Mount Bosavi by helicopter, courtesy of WWF, I didn't think
things could get any better, but I was wrong.
Accompanied by my field
assistant, Lawrence Kage, I was driven by car from the WWF base at the Chevron
oil camp at Moro along the road that follows the main pipeline from the
oil wells around Lake Kutubu in the Southern Highlands to the coast in Gulf
Province where the pipeline continues to a marine terminal outside the mouth
of the Kikori river. Only an hour out of Moro, we were halted by a flood
on the road and were just on the point of turning back when we made radio
contact with our hosts in Kantobo who agreed to meet us on the other side
of the flood. Having ferried our gear across the rather unappealing, tepid
water, we were met by Pamero, a wizened old man with dreadlocks and a serious
lust for life, who drove like a lunatic, although he could only just reach
the steering wheel, along the limestone road to a point where a path led
into the forest. There we met porters who helped us carry our gear down
to a launch on the Mubi river. Pamero being some what multitalented, took
control of the boat and, having introduced us to the villagers at Kantobol
set off to take us some 15 minutes downstream to the lodge where accommodation
had been arranged. As I relaxed in the knowledge that we were actually going
to reach our destination, I took more notice of my surroundings. Either
side of the broad river, whose turbid waters flowed calmly, but swiftly,
magnificent forest rose from the alluvial flats along the banks clothing
the limestone hills behind. Along the river margins, some ubiquitous New
Guinea tree palms, or limbuns, to use the PNG pidgin term, could
be seen. Metroxylon sagu, the sago palm, grew gregariously in large
quantities, which is fortunate, as the local people are dedicated and enthusiastic
sago eaters. Here and there, flowering specimens could be seen, spreading
their massive candelabras of inflorescences high above the foliage. These
individuals are quite useless to the local people as the energy required
for this reproductive effort exhausts the edible starch, which is stored
in the trunk of the palm before flowering. It is nevertheless an impressive
sight. Groups of Gulubia costata, the most common of all the robust
tree palms in New Guinea, were frequent. It is readily distinguished by
its spherical crown of straight leaves with drooping leaflets, although
this character is not reliable as it is shared by some species of Gronophyllum,
Rhopaloblaste, and Cyrtostachys. The presence of a brush-like
inflorescence narrows the options down to Gulubia and Gronophyllum
and, although probability suggests that the palm in question is Gulubia
costata, a closer look at the flowers is needed to be certain. Among
the gulubias, a few individuals were spotted with large, spreading inflorescences
which I tentatively identified as Cyrtostachys peekeliana. Striking
among these typical pinnate palms was the bipinnate Caryota rumphiana,
a robust member of the fish-tail palm genus, which is common throughout
the island.
Disembarking at a bend
in the river, we were led along a board walk through the bush to the lodge.
As we approached, I was distracted from rattan spotting when a hitherto
distant rumbling noise became gradually louder, up to the point where it
was difficult to communicate with anyone unless they were standing close
by. Arriving at the lodge, I walked to the edge of the river bank to find
myself on a cliff a hundred feet above the river, which was now hurling
itself over a great precipice into a deep limestone gorge. Equally awe-inspiring
was the forest, which towered above the gorge on the opposite side, presenting
a fantastic view of the different layers of vegetation that appeared to
be sewn together by rattans and lianas of various kinds. This was the dramatic
beginning of Wassi Falls, possibly the most spectacular chain of waterfalls
to be seen in New Guinea.
During that evening,
we made plans for the next few days of fieldwork. Lawrence visited Kantobo
village to gain permission from the landowners to collect in the area. Unlike
most other countries, PNG has retained traditional land rights and it is
vital to talk to the local landowners before doing anything on their property.
The following day, two guides from the village joined us for our first day
collecting around the falls and this proved to be extremely productive.
I found six species of Calamus, including three that I had not
come across before. Although this number may not be as high as that which
one might find in, say, most sites in Borneo, it was certainly a good score
for PNG. Unsurprisingly, the widespread Calamus hollrungii was
present. I encountered this species in every locality that I visited and
was very much bewildered by the variation that it displayed. For example,
some individuals bristled with numerous black, triangular spines, which
would penetrate my thick leather gloves as I tried to make a specimen, but
others were totally unarmed on the sheath. An extensive study is needed
before any meaningful taxonomic entities can be identified within this complex.
Another particularly interesting rattan found in the area was Calamus
humboldtianus. It had an altogether peculiar feel about it with its
large leaflets, leathery and somewhat hooded, crowded on a disproportionately
short rachis with a long petiole. The most remarkable feature was a structure
known as an ocrea, which is an extension of the leaf sheath above the insertion
of the petiole. Although ocreas occur in many rattan genera, they are a
great speciality of New Guinea Calamus species. The ocrea of C
humboldtianus is one of the most spectacular, reaching a length of
80 cm or more. It is blackish purple in color with numerous collars of soft,
fine spines.
Several small palms
grew in the undergrowth. A slender Areca related to A. novohibernica
was common, as was a species of Calyptrocalyx, which I had
already found in abundance around Mt. Bosavi. The latter was a particularly
ornamental palm. Its regularly pinnate leaf was an exquisite copper shade
on emergence and bore elliptic leaflets whose apices were drawn into fine
pendent drip tips. A very dwarf Gronophyllum of the type previously
known as Nengella was also present ...
|
