A herbarium is a collection of dried plant specimens that bear witness to the existence of plant species at different stages in their life cycles, in diverse locations on the planet, and at precise moments in human history. In this manner, each specimen possesses intrinsic heuristic and heritage values and cannot be replaced. The idea of collecting plants goes back to the first stumblings in botany. At that remote time, plants were primarily destined to be used for medicinal purposes. The botanists therefore only collected living plants which they cultivated in a garden: this was the herbarium vivum or living herbarium.
With the coming of the sciences, an interest in vegetation began to develop that was beyond their strict medicinal usages. The number of known plants increased and their geographic origins diversified. Paralleling this, the number of species that were difficult to cultivate in their gardens increased. It therefore became more practical to press and dry the plants and mount them on paper in order to preserve them for a long time. Thus the herbarium siccum or dry herbarium was born. The practice of accumulating specimens and building facilities to preserve them became more widespread and herbariums were constructed in all of the centers where science was flourishing. The oldest herbariums, which were spared from wars, fires, insects, and other plagues, are found in Florence and Bologne in Italy, as well as in Leiden in the Netherlands. They date back to the 16th century.
The herbarium siccum, despite its popularity, did not completely replace the herbarium vivum. Indeed, they have persisted up to the present in the form of botanical gardens which, while still playing an important scientific role, have had their original mission to heal diseases be replaced by one emphasizing their aesthetic value. Today, the term “herbarium” applies only to the herbarium siccum.
A herbarium specimen is above all a witness to the existence of a plant species at a specific location at a given moment of time. In regards to the profound natural and anthropogenic modifications which have occurred and are still occurring to the vegetation cover of our planet, herbariums are extremely important places of scientific and cultural heritage. Herbariums constitute an important part of our “vegetation memory”. The other part of this memory is preserved in published scientific works.
In addition to their heritage value, herbariums are important teaching and research tools for several disciplines including botany, taxonomy, phylogeny, ecology, and biogeography. In order to play an essential role in these domains, a herbarium must possess three fundamental characteristics: it must assemble the greatest number of species possible, include all of the ontogenical development stages for each species, and contain a large number of specimens for each species.
A herbarium is firstly a place to preserve the diverse vegetation of a given region and secondly a tool to identify plants, at any stage of development, by comparing them with the specimens in the collection. The latter is certainly the most common usage of herbariums, as it is this fundamental starting point in plant knowledge that attracts amateurs, students, professors, and professionals in the plant sciences to herbaria.
The Louis-Marie Herbarium offers this how-to guide to anyone who may be interested in making a herbarium.
Template - Mac Office2016 (etiquettes_herbier.zip)
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Microsoft Excel et Word files
The collection of specimens needs to be done with respect for the private property and for the laws governing the parks, nature reserves and preservation zones. Furthermore, the collector must be aware that in order to protect the biodiversity of Quebec, to date, 78 taxa are protected by the law. The list of species is available on the government of Quebec website:
Espèces floristiques menacées ou vulnérables
The pressing and drying method will vary according to the different plant group. The pressing itself consists of placing a specimen in between newspaper sheets, spreading it in its natural standing position, and pressing it flat to dry so it can ultimately be mounted on a cardstock. While spreading the sample, make sure that both sides of the leaves are visible, and turn the flowers or fruits in various directions so that every sides will be visible. On hot and sunny days, it's important to quickly press the specimens or to keep the plastics bags containing the samples in the shade.
Pressing and Drying Equipment
Mounting method will vary according to the different plant group. Once mounted, vouchers should be stored in cabinets away from light, and at a constant air humidity ranging from 30 to 50%. Mesures to prevent against insect pests damages should also be taken. In these conditions, the dried plant specimens should keep for centuries.
Specimens are secured to 29 x 42 cm white cardstocks (A3, tabloid or 11 x 17 in format) using archival grade gummed linen tape. The label is placed at the bottom right corner.
In the field, leave the press in full sun, or on the luggage rack of a car, taking care of aligning corrugation flute to allow maximum air flow through the press.
In the laboratory, use a low heat-source, such as two 60 W bulbs in a plant drier. The press is built by stacking corrugated cardboards and foam (i.e., cardboard-foam-plant in newspaper-cardboard). Fasten Compress between two hardwood board and fasten with the straps. Drying can take up to 48 hours.
Fleshy plants, seaweeds and aquatic plants take more time to dry. Rotating the press everyday over the dryer should help getting a more uniform drying. Once dry, remove the specimens from the press and store in a dry place, away from direct light and insect predation. A fast and effective drying will help preserve the plants' original colors. It is however preferable to avoid overheating the specimen. Do not exceed a tempertature equivalent to that of two 60 W light bulbs.
The following informations noted in the field, in a notebook, will later help to make a label for the herbarium specimen.
L'étiquette qui accompagne chaque spécimen d’herbier est imprimée sur du papier de The label should be printed on acid-free paper and contain the following information:
Fungi
Lichens and bryophytes
