If you come across a plant in Hong Kong and you wished to know its name, how would you find out? In this article, we will explore and explain how a library of plant diversity is build up and organized and how this can help you finding the name or other information about specific plants.

What is a plant specimen?

Unless you happen to know a good botanist, perhaps the quickest way would be to consult a local flora or checklist of native plants, which ideally would have been published by a reputable institution. Hong Kong, for example, has the four-volume Flora of Hong Kong series, published by the Agriculture, Fisheries and Conservation Department (AFCD) with technical support from South China Botanical Garden. In addition, there are a number of excellent books and articles on native Hong Kong plants, some of them published by KFBG. Such publications represent an as-complete-as-possible record of all plant species that naturally occur in a region, and are generally based on specimens.

A plant specimen is a permanent, scientific record of a species found growing at a particular location at a particular point in time. It consists of a piece of the actual plant, either pressed, dried and mounted onto a sheet or preserved in alcohol. A complete specimen should be labelled, bearing information on who collected it, where and when. Specimens are the foundation of plant research, and all scientific names for plants are linked to a specific specimen. They are stored in herbaria – libraries of preserved plant specimens arranged in systematic order as a reference collection of a region’s plants.

The history of plant specimen

In 1544, Italian botanist Luca Ghini (1490–1556) invented the technique of preparing herbarium specimens. Prior to this, plant research relied on observations and drawings, and was therefore limited to the period of time when a plant could be seen alive. With this invention, herbarium specimens could now be brought back indoors for long-term storage and study. Well-made specimens capture important characteristics such as leaf shape and arrangement, flower presentation and fruit type. Together with complete collection information, they form a critical scientific record of plant morphology, geography and ecology. The emergence of herbarium specimens greatly facilitated plant identification and nomenclature, and plant research has since entered a new era.

Since the nineteenth century, a large number of botanists started surveying and collecting wild plants in Hong Kong and Southern China. The specimens they collected are deposited in several herbaria in Hong Kong, the United Kingdom, the United States, and mainland China, and these have become important resources for studying plant diversity over the intervening period. Based on these specimens, botanists have published numerous new species, many of them named after Hong Kong – such as the Hong Kong azalea, Rhododendron hongkongense, for example. The number of identified (or known) vascular plants (ferns, gymnosperms and flowering plants) recorded in Hong Kong has grown to more than 2,200 species today, and this number (as well as the number of plant specimens) continues to grow every year. In the last 10 years alone, KFBG botanists have added 36 plant species to known flora of Hong Kong! This is a sure indication that our understanding of the biodiversity we seek to protect is still far from complete.

Plant Specimen in science

Specimens serve as a voucher for the existence of species new to science. To describe a new species, botanists must first be very familiar with all known species of a particular group (family or genus) so that they can determine whether the species has previously been described or not. And if not, a scientific name needs to be provided. The name is only accepted by the scientific community if the species is published properly with a full description of the plant’s morphology and distribution, as understood by an analysis of available specimens. Indeed, the paper must include information of the very specimens studied by the botanist and the herbarium where they have been deposited.

A label is essential for this purpose. Surprisingly, the most important information recorded on the label is not the plant’s scientific name or the family it belongs to, but the collector’s name and collection number, the date, and the location where the plant was found. It takes some training to record this information properly.

The KFBG Herbarium

Given all this, KFBG’s dedication to exploring, documenting and conserving Hong Kong’s plant life requires it to maintain its own refence library of local plants – its own herbarium.

Our field botanists routinely venture out into the countryside in search of novelties and rarities, and record what grows where. The specimens they collect are passed to our herbarium staff for processing. After going through the process of pressing, drying, mounting, sterilisation, barcoding and digitisation, the specimens are ready to be deposited in herbarium cabinets. The KFBG herbarium is kept cool and dry year round, providing a suitable environment for the long-term preservation of specimens.

At present, there are five herbaria in Hong Kong: AFCD’s Hong Kong Herbarium (HK), the Shiu-Ying Hu Herbarium at the Chinese University of Hong Kong (CUHK), the KFBG Herbarium (KFBG), The Hong Kong University Herbarium (HKU), and the Baptist University Herbarium (HKBU).

The KFBG Herbarium was established in 1990 by Gloria Barretto (1916–2007) and it now contains more than 18,000 specimens. Most of these have been digitized, i.e. scanned and databased for easy retrieval. The main collectors of the specimens held in our herbarium are Gloria Barretto, Chang Hung-Ta, Xing Fu-Wu, Zhang Li, Yan Yue-Hong, Ng Sai-Chit, Liu Jin-Gang and Zhang Jin-Long. Our collection of ferns and woody plants is particularly remarkable. Our oldest specimens date back to 1971 and, if well looked after, should remain functional for hundreds of years to come.

Gloria Barretto was a botanist of Portuguese descent who started collecting herbarium specimens in the 1970s. She had a strong interest in orchids and published several new orchid species together with renowned Chinese plant taxonomist Shiu-Ying Hu. Gloria’s lifelong interest in orchids culminated in the posthumous publication of The Wild Orchids of Hong Kong in 2011, still the most comprehensive book on orchids in Hong Kong to date. Many of the specimens she and her co-authors Phillip Cribb and Stephan Gale studied in preparing the book are stored in KFBG’s herbarium.

Visitors are welcome to examine the plant specimens held in our herbarium by appointment. Our opening hours are 09:00–17:00, Monday to Friday. Please contact our curators in advance at jlzhang@kfbg.org. The herbarium also occasionally offers positions for summer interns and volunteers: https://www.kfbg.org/en/facilities/herbarium. By paying us a visit, by speaking with our botanists, or by reading one of our publications, you should find a name for that plant!

Jinlong Zhang, Kit Lee (Flora Conservation Department)