Voucher specimens, the DBN herbarium and BSBI county recording

Botany with your own herbarium voucher specimens available from previous field work allows for anatomical understanding of higher plant parts.

Only recently I was informed that a pomegranate produces 613 seeds. In checking this out further online, the ‘pomegranate seed’ statistics are on http://www.aquaphoenix.com There are numerous other anatomical features of botanical interest that can be studied with a fruit-bowl, and one’s imagination that values scientific activity and questioning. Almost fifteen ago, a bug found by a breakfaster in microwaved porridge from somewhere along the east coast of America arrived in Dublin for forensic analysis and was passed along to the herbarium for investigation. Dissections of the bug returned a satisfying result that it was an edible blueberry, Vaccinium corymbosa (Ericaceae).

As a botanist into the identification of lichens, mushrooms, micro-fungi, mosses, liverworts, slime moulds and seaweeds, my use of vascular plant herbarium resources has been focussed mainly on woody plants (trees and shrubs; native and introduced) as substrates for epiphytic life.
Higher plant parts that I am interested in, as part of epiphyte ecology, include twigs and branches with bark, buds, leaf and bud abscission scars, dead attached branches with bark, trunk bark, and twig and branch timber with tree rings. Terminal branches from leafless hedgerow bushes collected in winter from September to April in the farmed Irish landscape can be very challenging to identify without herbarium reference collections. Willow, hawthorn, sycamore, ash, sitka spruce, etc. can all be placed.

With herbaceous plants, one becomes interested in what specifically rots them down, and one begins to gather interesting plant leaves with rusts and mildews, and herbaceous litter stems from deep ditches and hedgerows for dainty ascomycete fungi for study. When one is walking by the sea, beachcombing, it is always interesting to attempt to identify plant and plant parts in the sand. Sources include wetland, dune front and salt marsh plants, with river mouth flotsam including riparian tree and reed parts. A standard reference is Ellis & Ellis’s Microfungi on Land Plants. This is now in its second 1997 edition. Ellis and Ellis consider land plants as substrates for fungi and have the following categories (1) plurivorous wood and bark fungi, (2) plurivorous leaf litter fungi, (3) fungi specific to trees, shrubs and woody climbers, (4) plurivorous fungi on herbaceous plants, (5) fungi specific to herbaceous plants in general, (5) plurivorous fungi on grasses, (6) fungi specific to grasses, (7) fungi specific to rushes, sedges, bur-reeds and reed maces, (8) fungi specific to ferns, horsetails and clubmosses, (9) fungi parasitic on rusts and powdery mildews. The jargon plurivorous refers to fungi feeding on many different kinds of plant in a non-specific way. Analagously, one could suggest most corticolous lichens are pluricolous, each species living on many host tree genera.

In order to broaden one’s experience in botany in the field, becoming a specialist in locating plants in the landscape is a very satisfying apprenticeship. Herbarium resources are built from reference collections needed by botanists, and are made for various botanical purposes. In DBN, we are keen to support floristic botany in Ireland, and our collections are open for researchers to visit and consult. We have kept a wide range of voucher samples from floristic explorations, and from ecological studies, and have filed all plant flowering shoots in a systematic sequence. There are collections of seeds, timber anatomy slides, DNA extracts and other reference materials of value for the identification of plants, and plant parts, to their botanical species. Frodin’s (2001) Guide to standard Floras of the world is a compendium of the literature created and written by botanists for botanists for use in each geographical region. This provides a good guide to what can be made with herbarium specimens. Womersley (1981) shows how ethnobotanical collections can lead to a herbarium. Dalby & Dalby (1980) provide advice on line drawing from specimens. Mitchell (2000) gives a list of floristic botanical publications in Ireland. Since then, more works have appeared (Fox, in manuscript). Lawrence & Hawthorne (2006) advise on making plant identification keys and they set out the steps involved in making such publications from herbarium voucher specimens, written with the primary purpose of assisting people with plant identification.
I would like to conclude this article by calling for the making of herbarium specimens from one’s own ad hoc collections of plants and plant tissues. Being in the field, doing botany is an expense and a luxury to satisfy ones nosiness for what grows where, and how to find it. Making voucher specimens suitable for addition to herbarium collections is a worthwhile end use for plant materials gathered from a day’s botany.

As part of a network of herbaria globally (Thiers 2011), we in DBN can support this activity of keeping herbarium specimens in a practical manner (OPW, 1992). Herbarium labels and standard mounting sheets for use with wood glue can provide impetus to encourage one to tend to processing one’s plants, pressed and dried, in folded newspapers, into something more formal and permanent. We use Evostick wood adhesive and cut out straps from paper to mount material. For advice on methods, one can turn to the herbarium handbook (Bridson & Forman, 1998).

If you are recording plants with the BSBI in Ireland, do visit us in DBN to see how your ad hoc plant gatherings, that support your studies and intellectual explorations of plants in Ireland, can be made into something more.

References:
Bridson, D. & Forman, L. 1998. The Herbarium Handbook. 3rd edition, xii, 334pp. Kew: Royal Botanic Gardens.
Dalby, C. & Dalby, D.H. 1980. Biological illustration: a guide to drawing for reproduction. Field Studies 5: 307-321. http://fsj.field-studies-council.org/media/343259/vol5.2_135.pdf
Ellis, M.B. & Ellis, J.P. 1997. Microfungi on Land Plants: an identification handbook. New enlarged edition. The Richmond Publishing Company Ltd. 868pp.
Frodin, D.G. 2001. Floras at the end of the twentieth century: philosophy, progress and prospects; references: 52– 85. In D.G. Frodin. Guide to Standard Floras of the World: An Annotated, Geographically Arranged Systematic Bibliography of the Principal Floras, Enumerations, Checklists and Chorological Atlases of Different Areas. 2nd edition. 1107pp. Cambridge University Press, Cambridge.
Lawrence, A. & Hawthorne, W. 2006. Plant Identification. Creating User-friendly Guides for Biodiversity Management. 1st edition, xvi, 268pp. Earthscan. London.
Mitchell, M.E. 2000. The Irish floras: a checklist of non-serial publications. Glasra 4: 47–57. http://www.botanicgardens.ie/glasra/ns4_3.pdf
Office of Public Works. 1992. National Botanic Gardens Management Plan. Stationery Office. Dublin. 40 pp.
Thiers, B. 2011. Index herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. http://sweetgum.nybg.org/ih/
Womersley, J.S. 1981. Plant collecting and herbarium development. A manual. In: FAO Plant Production and Protection Paper (FAO), No. 33 / FAO, Rome (Italy) 146 pp.

Reprinted from
BSBI Irish VCR Newsletter #5: 9-10, (December 2015).
http://www.bsbi.org.uk/ireland.html

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