Schima







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By William A. McNamara
"On the way to Darjeeling…the roads…from March to May - are found strewn over with the white flowers of Schima Wallichii." Biswas, 1966
Schima is an attractive genus of evergreen trees of sub-tropical and warm temperate regions of Asia. Once considered to contain up to fifteen species, it is now thought by some to be only one variable species, due to a revision of Schima published in 1952 by S. Bloembergen placing them all under Schima wallichii (DC.) Korth. It is a member of the Theaceae, the tea family, and is closely related to the genus Gordonia. They occur from Nepal and India eastward to Taiwan at elevations of 200 to 2500 meters. Most become quite tall with some reportedly over 40 meters. They have showy fragrant white flowers 4 to 6 centimeters across with five petals and numerous yellow stamens. These bloom on pedicels 1.5 centimeters long in the terminal axils of the spring growth. This is accompanied by a flush of delicate shiny red new leaves.
I have seen and collected seeds from Schima in the wild in four different areas. The first time was in October of 1991 in western Sichuan on Erlang Shan at 1820 meters elevation. Only one tree was seen. It was a narrow tree to about 7 meters high growing among dense regenerating vegetation. The steep mountainsides had previously been logged and were now a dense jungle of competing trees and shrubs. The few seed capsules found were near the top of the tree. These were brown globular capsules about 1.5 centimeters across similar to camellias. Carpinus fangiana, Pterostyrax psilophylla, and Idesia polycarpa were growing nearby along with a number of rhododendrons, hydrangeas, roses, clethras, and viburnums. I have been to Erlang Shan several times and always found it to be very wet and almost always raining. The Erlang Shan typically receives over 120cm of rain in the summer months with occasional rain throughout the rest of the year.
The next time that I collected Schima was in October of 1992 returning from Muli west of Xichang in southwestern Sichuan at 2330 meters elevation. Again, only one tree was seen. It also was a narrow tree in an area of dense regenerating trees and shrubs. Like Erlang Shan, this area also receives heavy summer rainfall, although the annual rainfall is less.
The third time that I collected Schima was in October of 1993 in Nepal. There it is called Chilaune and is used in construction as well as for medicine. The leaves and roots are used for fevers and the bark is sometimes used for intestinal worms. They were growing about 10km west of Nargarkot at an elevation of 1590 meters. Unlike the two previous times, here they were plentiful. They dominated the north-facing mountainsides along with Pinus roxburghii, Castanopsis indica, and Alnus nepalensis. These Schima had rounded crowns and were from 7 to 10 meters tall.
The last time that I saw and collected Schima was in Taiwan in October of 2004. Here they were abundant and very tall, with some reaching 30 meters. Ignoring Bloembergen's revision, local botanists consider the species to be Schima superba Gard. & Champ. They were growing on a very steep northwest-facing mountainside with Acer serrulatum, Alnus formosana, Abies kawakamii, and Tsuga chinensis var. formosana at an elevation of 2150 meters in Taroko National Park. Locally the wood is used in construction, while the bark serves as a fish poison.
Although the bark is said to be a skin irritant, I suffered no harm from climbing these trees to gather the seed capsules. Of the four collections, only the first two have germinated for us. It is too soon to see if the final collection will germinate as it was only seeded in December of 2004. From the 1991 collection we now have two vigorous trees, one 10 meters tall by 6 meters wide and the other 7 meters tall by 6 meters wide, after only twelve years in the ground. Sadly, three others planted around the same time have succumbed to oak root fungus (Armillaria mellea). All were planted within a few months of each other in 1992. The survivors are both in full sun on a gentle west-facing slope. We also have one young tree started from a cutting that was planted in 2001 that is now 2.5 meters high. All are growing as low-branching single trunk trees and have large dark green leaves 18cm. by 5cm. with serrate margins. They start blooming in September and have two large bracts wrapping the bud. It took them five years in our garden to begin blooming.
From the 1992 collection we have two plants in the garden. The first was planted in the summer of 1994 and has grown much slower than the previous collection reaching only 3.5 meters in ten years. The other is from a cutting of the first and was planted in 2001. They are both growing into round shrubs, almost as wide as they are high and have considerably smaller flowers than the 1991 collection. The bluish leaves are distinctly smaller also, 9cm by 3cm, and have entire margins. They start blooming in July and have much smaller bracts surrounding the bud. This Schima also took five years to bloom in our garden.
In reading about these interesting trees and curious as to why they had been lumped under one name, I found several peculiar inconsistencies in the available literature. In leaf shape, our two Schima appear to match two of the line drawings in Gerd Krussmann's MANUAL OF CULTIVATED BROAD-LEAVED TREES & SHRUBS. This reference does not mention Bloembergen's revision and states that there are 15 species. It describes three of them, S.argentea Pritzel., S. khasiana Dyer., and S. wallichii (D.C.) Korth. The three line drawings however, are of S. argentea, S. wallichii, and S. noronhae. Our 1992 collection is similar to their drawing of Schima argentea and our 1991 collection is similar to their drawing of Schima noronhae. Krussmann's line drawings are taken from the ICONOGRAPHIA CORMOPHYTORUM SINICORUM TOMAS II. Despite having a line drawing labeled S. noronhae, the text implies that S. noronhae should be S. wallichii.
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The descriptions of two species of Schima in TREES & SHRUBS HARDY IN
THE BRITISH ISLES, seem to fit ours. Our 1991 collection appears to be
what they call S. khasiana and our 1992 collection appears to be what
they call S. argentea. They do mention the revision though, and go on to
state that S. khasiana should be known as S. wallichii subsp. wallichii
var. khasiana and that S. argentea should known as S. wallichii subsp.
noronhae var. superba.
If that isn't confusing enough,
several references refer to the bud as being red or scarlet. HORTUS
THIRD and the INDEX OF GARDEN PLANTS both read "scarlet in bud". The
MANUAL OF CULTIVATED BROAD-LEAVED TREES & SHRUBS states "flowers
scarlet-red in bud". None of our Schima however, display this
characteristic and instead are creamy white in bud.
Several of
the references refer to the flowers as blooming in April, May and/or
June. Frank Kingdon-Ward in PLANT HUNTER IN MANIPUR mentions Schima as
being "covered in June with large Camellia-like fragrant creamy white
flowers with a large central brush of orange stamens". Roy Lancaster in A
PLANTSMAN IN NEPAL writes "the schima with its attractive white
fragrant camellia-like flowers in April to June make a magnificent tree …
in the eastern Himalaya". In the TREES AND SHRUBS OF NEPAL AND THE
HIMALAYAS one reads "The flowers, which appear in May…" and lastly,
according to the FLOWERS OF THE HIMALAYA, Schima wallichii blooms in
May-June.
Ours however, bloom in late summer and into the fall. The MANUAL OF
CULTIVATED BROAD-LEAVED TREES & SHRUBS says that S. argentea blooms
in August, S. khasiana blooms in September-October and S. wallichii
blooms in the late summer. THE HILLIER MANUAL OF TREES & SHRUBS,
despite mentioning the revision by Bloembergen, describes four species
with S. argentea blooming in late summer, S. khasiana blooming in
September and October, S. noronhae blooming in late summer and autumn,
and S. wallichii blooming in late summer. In the paragraph above, all
the Schima described were in the wild, while those referred to as
blooming in the late summer and autumn, were all cultivated trees.
Perhaps this is an anomaly of cultivation in Western Europe and North
America. I did, however, see a few lingering flowers on naturally
occuring Schima superba in Taiwan last October.
In discussing the
cultivation of Schima, THE NEW ROYAL HORTICULTURAL SOCIETY Dictionary
of Gardening, mentions that they should be protected from frost when
young and that if under glass the temperature should not drop below 3-5
degrees centigrade. Ours were planted out quite young (the 1991
collection were one year from seed and the 1992 collection was 2 years
from seed) and have experienced numerous frosts every winter with
temperatures as low as -8 degrees centigrade. Both were less than 30
centimeters high in 4" pots when planted in the ground. None of them
have suffered from our frequent frosts.
Clearly, our experience has shown that Schima have promise as ornamental
trees in California. Along with showing no frost damage in Sonoma
County in Sunset's zone 14/15, they have withstood our intense summer
sun with no sign of sunburn. To date, there are no signs of insect
damage either. Unlike many introduced exotics, they have not reseeded in
our garden, nor have they suckered. They are also resistant to fire.
Though not heavy bloomers, they are in flower at a time when little else
is. Their lush evergreen leaves have a cooling effect in summer and
contrast nicely with the starkness of winter. Other than their
occasional susceptibility to oak root fungus, which I believe can be
ameliorated through proper culture, they seem ideal ornamentals. The
fragrant white flowers of this little known tree could easily compliment
many gardens.
ReferencesBAILEY,
L.H. & BAILEY, E.Z. (1976). Hortus Third, A Concise Dictionary of
Plants Cultivated in the United States and Canada. Macmillan Publishing
Company, New York, New York.
BEAN, W.J. (1989). Trees & Shrubs Hardy in the British Isles, Volume IV. John Murray Ltd, London, England.
BISWAS,
K. (1966). Plants of Darjeeling and the Sikkim Himalayas, Volume I.
West Bengal Government Press, Alipore, West Bengal, India.
GRIFFITHS, M. (1994). Index of Garden Plants. Timber Press, Portland, Oregon.
GRIFFITHS,
M. (1992). The New Royal Horticultural Society Dictionary of Gardening,
Volume 4. The Macmillan Press Limited, London, England.
HILLIER, H. (1992). The Hillier Manual of Trees & Shrubs. David & Charles, Devon, England.
KANEHIRA, R. (1973). Formosan Trees. Inoue Book Company, Tokyo. Japan.
KINGDON-WARD, F. (1952). Plant Hunter in Manipur. Jonathan Cape, London, England.
KRUSSMANN, G. (1986). Manual of Cultivated Broad-leaved Trees & Shrubs, Volume III. Timber Press, Portland, Oregon.
LANCASTER, R. (1995). A Plantsman in Nepal. Antique Collectors' Club Ltd., Woodbridge, Suffolk, England.
POLUNIN, O. & STAINTON, A. (1988). Flowers of the Himalaya. Oxford University Press, New Delhi, India.
STORRS, A. & STORRS, J. (1990). Trees and Shrubs of Nepal and the Himalayas. Pilgrims Book House, Kathmandu, Nepal.