EcologyExcursion Report


Prepared for botany class: Resource for the future

Closer to Botanical Garden
A botanical garden can be defined as a place where a wide variety of plants are cultivated for scientific, educational, and ornamental purposes, often including a library, a herbarium, an arboretum and greenhouses (Thesaurus; 2008)

The history of botanical gardens is closely linked to the history of botany itself. The earliest botanical gardens were founded in the late Renaissance period at the University of Pisa (1543) and the University of Padua (1545) in Italy, for the study and teaching of medical botany (Wales;2004). The botanical gardens of the 16th and 17th centuries were medicinal gardens but the idea of a botanical garden changed to encompass displays of the beautiful, strange, new and sometimes economically important plant trophies being returned from the European and other distant lands. Later, in the 18th century they became more educational in function, demonstrating the latest plant classification systems devised by botanists working in the associated herbaria as they tried to order these new treasures. Then, in the 19th and 20th centuries, the trend was towards a combination of specialist and eclectic collections demonstrating many aspects of both horticulture and botany.(Hill, Arthur; 1915). Over the years botanical gardens, as cultural and scientific organizations, have responded to the interests of botany and horticulture.

In Japan there are almost 120 botanical gardens and at least six research institutes associated with these botanical gardens including Hiroshima Botanical Garden. Their size, characteristics, and plant collections, as well as activities, differ from one another. This makes Japanese botanic gardens very diverse and dynamic.  Many garden visitors enjoy, special collections of Japanese native plants from mountainous regions, deciduous woodlands and various aquatic habitas, and the plant collections representing the history as well as traditional skills and knowledge of Japanese horticulture. (Botanic Gardens Conservation International; 2010)

Objective of Excursion
To understand about Hiroshima Botanical Garden, its function, plants, and a conservatory for the fresh arrived international students of IDEC, Hiroshima University.

Schedule of Excursion

Hiroshima Botanical Garden

Hiroshima Botanical Garden is located at north latitude 34°23', and east longitude 132°20' in western Honshu facing to the Seto Inland Sea. Located on the hill 60~153m above sea level, it commands a whole view of Miyajima Island.The land area of the garde n is 18.3 hectares and quite undulated. The climate is mild; the annual mean temperature is 15.0°C, mean temperature of January is 4.0°C and August is 26.9°C, and the mean annual precipitation is 1554.6mm.
The garden is municipal and was established on November 3, 1976 for citizens, as relaxing and educational places to deepen their knowledge of plants and of nature conservation. The garden incorporates research laboratories, main conservatory, begonia displayhouse, fuchsia displayhouse, phylogenical garden, rock garden, Japanese garden, camellia garden utilizing the undulated land effectively.
There are 38 permanent staff working for the garden (4 of them hold a PhD and 50% of them are still continuing PhD). Also there are 61 part time staff who take part in the work directly concerned with plant, maintenance and cultivation.

Plant Collection and Preservation
The garden has always made an effort to collect plants since it has opened, and keeps about 11,700 taxa at the present time. In particular, the garden has collected Orchidaceae, and keeps 2,600 taxa, 29,000 plants of them.Those collections are used for exhibition or for study purposes. The garden also preserves Japanese classical horticultural plants such as morning glory and Japanese primrose and shows them to the public through each exhibition.

Begonia Conservatory
One of the conservatories in Hiroshima Botanical Garden is Begonia Foyer. It is one of the biggest conservatories in western Japan which covers around 400m2. For growing Begonia, there are three types of Begonia development such as cutting, rhyzome, and tubber. In this part, there are 1,680 kinds of species from Japan and mainly from south America.

The control of the lighting enables the tuberous begonias to bloom, so we can enjoy large, bright flowers of those begonias all year around. The foliage begonias whose leaves are uniquely shaped or beautifully patterned are exhibited too.

Greenhouses Conservatory
The main conservatory is 2,186m2, and there are about 970 taxa, 14,160 individual plants from tropical to subtropical areas. When we went inside the conservatory, we could see tropical fruits, tall palms, Orchids and so on, and we felt as if we were in a tropical rain forest. The tall plants like queen palm or traveler's tree can grow to their full capacity because the conservatory is 21 meters high. Epiphytic orchids are put on the trees or the rocks in the conservatory; the natural habitat of those plants are simulated.

In the cactus displayhouse, not only Cactaceae but fleshy plant of Aizoaceae, Liliaceae, Asclepiadaceae or Vitaceae which adapted to arid land are exhibited. We can see their unique shapes of occurring from their adaptation to the environment.

About 50 species of tropical water lilies and Amazon water lilies were exhibited in the tropical water lily displayhouse. The clear violet, blue, pink or yellow colors of the flowers attract visitors. There are about 650 species and over 2,000 individual plants of begonias in the begonia displayhouse. This displayhouse is equipped with the air conditioning and the climate is kept cool in summer and warm in winter.

There were up to 10 nursery greenhouses and the total sufrface area was 1,100m2, and they were used for raising seedlings for exhibition and preservation of plain strains, mainly of Orchids.

In the fuchsia displayhouse, we can see wonderful fuchsias called 'LADY'S EARDROPS' all year. We were attracted by enormous flower forms and colors from pure white to the extremes of violet.

Other Special Gardens

Phylogenical garden is designed to follow the phyletic line of seedplants from the primitive types to the advanced types, so that visitors can study about plant phyletic line as the y walk through the garden. The monocotyledons are planted on the left side of the main pass and on the right side, the dicotyledons.

Rose garden exhibits not only popular horticultural varieties but also 120 species of wild roses, 120 types of old roses which are the origin of the current horticultural varieties. There is also a corner of such as the one presented from Czechoslovakia to Hiroshima City as a symbol of the peace.
Arboretum is arranged by using the red pine forest effectively, which is a characteristic forest of Seto Inland sea coast. Maple forest, evergreen forest and deciduous forest are also simulated, and we could stroll around and observe them along a pass going through these trees.

Exhibition and Education Program
There are three exhibition sites in the garden. About 40 exhibitions such as displays of Orchids, Chrysanthemum as well as Japanese botanical arts are held in a year, so visitors can see a new exhibition almost any time they visit. Lectures according to the exhibitions are held occasionally, and visitors can gain new knowledge there. During the summer vacation of the primary and secondary schools, they also hold plant educational programs for school children. Children can study experimentally with real plants. Observation lectures of plants in the garden to the general public are held also according to the season.

Research Activities
Investigations of plant chromosomes, wild flora or plant conservation are undertaken in the garden.

Bailey, Liberty Hyde & Bailey, Ethel Z; 1978. Hortus Third. New York: Macmillan. ISBN 0025054708
Hill, Arthur W; 1915. The History and Functions of Botanic Gardens. Annals of the Missouri Botanical Garden
Botanic Gardens Conservation International
The Hiroshima Botanical Garden Brochure 2010
Botany Lecture Note of IDEC-Hiroshima University; 2010