INTRODUCTION Unfortunately, many or most herbaria throughout the United States have recently experienced significant neglect. Biology and botany programs have slowly discontinued taxonomic and organismal aspects of their curricula, and molecular and cellular emphasis has created a gross academic imbalance. Faculty specializing in taxonomy and natural history are not being replaced. The result has been not only the deterioration of important natural history collections, but an attitude has developed among many modern scientists who look at organismal biology as an outdated discipline that has no potential to contribute to science or society. This naive arrogance threatens the knowledge-base needed to train new scientists to identify organisms and understand their life histories and autecology. The fact of the matter is that there is a great need for organismal biologists and their collections. As habitat is lost to development, trained field biologists are needed to assess the impact of proposed development projects on local and regional biodiversity. On a larger scale, natural history collections represent a means to measure the change in the distribution and range of species as a result of climate change and anthropogenic disturbances (which may include climate change). Molecular biologists and geneticists will find that properly preserved and maintained collections facilitate a whole range of studies on both spatial and temporal scales. The short sightedness of individuals who view herbaria and other types of natural history collections as worthless antiquities precludes the use of such repositories for modern applications. |
HERBARIUM [hûr•bâr'î•ûm] noun, plural herbaria (from the Latin term herba = plant, and arium = a container or facility. 1) a collection of dried plants, usually mounted and classified; 2) the room or building where a dried plant collection is kept. Fungi and fungi-like protists have traditionally been classified as plants, so collections of these organisms are still called herbaria. The proper noun Herbarium as used in this publication refers to the Swinehart Herbarium as a collection (as in definition 1). The Mission of the Swinehart Herbarium 1. Provide a source of data for comparative studies of the relationships among plant groups, their patterns of variation, their evolution, and their ecology & geographic distribution. 2. Serve as a repository for research specimens that can be studied and verified by future investigators. 3. Provide reference for the precise identification of specimens. 4. Serve as an educational resource for undergraduate and graduate instruction in the botanical sciences. 5. To be a careful steward of the collection so that both existing and presently undiscovered applications will be feasible in the future. "From a scholarly point of view, an herbarium is its own excuse for being, not only as a collection of plants that once lived, but as an edifice built by the curiosity and care of hundreds of individuals. In some ways, the collections resemble those ancient churches in Sicily, where the Greek columns were joined by Roman arches, toped with Sarracen domes, and finished with baroque facades. Like such churches, an herbarium summarizes history. It records the human effort to penetrate the mysteries of nature, and the attempts of individuals to construct from apparent chaos an orderly system of thought" -Jeanne W. Halpern Curation Format Vascular plant specimens in the Swinehart Herbarium follow the standard format, where pressed plants of a given individual (whole or in part) are taped or glued to an herbarium sheet(s) having a standard size of 16.5 x 11.5 inches (except for the xylarium where wood specimens stand alone and are labeled directly on the specimen; or spirit collections which are in jars with liquid ethanol of formalin preservatives). Specimen labels are attached to the lower right corner of the sheet. Loose parts such as seeds, or fragments of vegetative and reproductive parts may be included in envelopes attached to the sheet. Bryophytes are placed loosely (not attached) in standard bryophyte envelopes, and these envelopes are attached to an herbarium sheet by staples. Several specimens of a given taxon may be mounted on the same sheet to save space. Sometimes sheets will include specimens of a taxon that are all from a similar locality, all specimens from a given county for instance. Many algae are probably best stored in spirit collections (preferably 60% ethanol with a small amount of Glycerine added to prevent desiccation). Some of the macro algae can be “floated” onto an herbarium sheet in a pan of water to maintain aquatic habit. Otherwise, the filaments become clumped into amorphous clods. Fungi (including lichens) are curated much like bryophytes when possible, however, large and voluminous specimens require that they be placed in appropriately sized boxes. These boxes are labeled and stored in a separate place in the herbarium. Blank sheets indicating the presence of a boxed specimen stored elsewhere may be placed with the mounted specimens. Some fungi are best kept in spirits to prevent loss of gross morphology as a result of drying. Arrangement of Specimens. Folders in the Swinehart Herbarium are arranged alphabetically by family, then genus, and specimens within a genus folder are arranged alphabetically by species. This facilitates easy access for a research collection, although many herbaria organize their specimens phylogenetically. Accession Numbers & Records. Accession numbers are assigned to each specimen, much like library books have accession numbers, and in the Swinehart Herbarium, they begin at No. 1. New accessions are recorded by hand with an ink pen in a record book with all appropriate data. Additionally, all the data in the record book are entered into a computer database comprised of numerous fields that allow searches by date of collection, date of entry, genus, species, family, location, etc. Restoration of Damaged or Deteriorated Specimens. Even some of the more recently collected specimens need work due to handling, etc. The policy established for the Swinehart Herbarium has been to give attention to restoration of specimens on a situational basis. In other words, when a folder is pulled, for whatever reason, specimens needing restoration are attended at that time. Acid-based paper. Most of the specimens in the Swinehart Herbarium have been mounted on acid-free paper. However, some specimens received from gifts and exchanges are mounted on acid-based paper. The acid used in the paper-making process can result in the disintegration of the cellulose fibers that make up the matrix of the paper. The acid can also migrate from paper to specimen and cause deterioration of the specimen. There is need for concern not only for individual specimens, but also other specimens stored in the same folder, because acid can leach from page to page. Evidence of acid deterioration includes yellowing, blackening, and brittleness/fragmentation. Sheets showing significant symptoms of acid deterioration should be remounted. This is done in one of two ways. If the plant is attached by tape, it can be removed from the old sheet, entirely, and remounted on new paper. If the specimen is tenaciously bound to the paper by glue, as much of the old paper as possible can be cut away and then the specimen and remaining paper can be glued to a new sheet. It is imperative that all labels and any form of writing on the sheet be cut out and saved. These items can either be placed in a glasine envelope and attached to the sheet, or they may be glued directly on the new sheet in the appropriate places. To determine whether a new sheet is suitable for mounting (non-acid based), use a pH testing pen. A color change to yellow indicates an acid reaction, a color change to blue or purple indicates a basic reaction. Depauperate or inappropriate labels. Although all specimens collected and mounted by me have standard labels, some specimens that end up in an herbarium from other sources may have labels of very poor quality. They range from note-cards, to scraps of paper, to no label at all (scribble directly on the sheet). If such labels are associated with a specimen slated for a new sheet, the old label should be cut off and put in a glasine envelope (attached to sheet), and a new label should be attached. Generally, typeset or printed labels from other individuals or herbaria are always appropriate, for example labels that say, Ex Herbarium of Delzie Demaree or Herbarium of Indiana State Teachers College. Moreover, any label from an historically significant collector or associated with an historically significant collection should not be removed or tampered with unless in a necessary restoration. Improperly attached specimens. It is always unfortunate to see a specimen in an herbarium that someone has attached to a sheet with transparent tape used for gift wrapping. No matter how good the tape looks at first, it is always destined to become an unattractive, useless, yellow scab on an otherwise worthy specimen. It is embarrassing for the person responsible. The crime is furthered by putting the specimen in the herbarium alongside more worthy counterparts. If a specimen is worth collecting, it is worth mounting and labeling properly. Even standard herbarium-quality cloth tapes can become detached, thus requiring adhesive. The good news is that most of these specimens can be restored by cutting the tape and removing the specimen and attaching it to a new sheet using a good quality, reversible, white glue. Loose parts. Fragmented plant remains are always a problem, especially with poorly mounted specimens. Large, meaningful fragments such as leaves and reproductive structures are generally placed in glasine envelopes and attached to the sheet. Sometimes, it is desirable to take very fragile fragments (that would otherwise become broken in an envelope) and re-glue them to the sheet either in their original place prior to breakage (if that can be determined) or on another area of the sheet. Herbarium specimen showing fragment envelope Discarding specimens. If the herbarium has been properly curated from its beginnings, the topic of discarding specimens is moot. However, carelessness can result in worthless specimens working their way into an herbarium. The primary consideration here is whether or not the curator should justify the space (both physical and in terms of computer memory that these specimens occupy). Most literature on herbarium curation including the excellent Herbarium Handbook by Bridson and Forman does not discuss the “unthinkable” topic of discarding specimens. However, it is the opinion of the author that there are certain instances when it is justifiable to discard a specimen, just as there are times when libraries discard books. The following list outlines criteria for discarding specimens in the Swinehart Herbarium. They are meant to be as conservative as appropriate for my herbarium. All of the criteria must be met before the specimen(s) can be discarded. 1. The specimen has no date. 2. The specimen has absolutely no location data. 3. The specimen was not collected or identified by a reknowned or noteworthy collector. 5. The specimen is not particularly rare or infrequent in the natural world. 6. There are at least five specimens of the same taxon of the specimen in question already in the herbarium. Procedures for discarding a specimen (once the above criteria have been met) are as follows. 1. Remove the specimen from the Herbarium. 2. Begin a notebook for discarded specimens. 3. Enter the accession number of the specimen and any information about the specimen in the notebook. Include justification for discard. 4. If the specimen has been recorded in a “Record of Collections” and or on a computer database, make note that the specimen has been discarded. 5. Discard the specimen. STANDARD FORMS & LABELS In many cases, the first impression that another institution has of an herbarium, is based on a letter or even a specimen sent through the mail. Therefore, it is extremely important that the design of printed materials reflect the high degree of excellence and professionalism that characterize the herbarium. The following forms and labels have been established in an attempt to meet these standards. Loan Forms. Loans of specimens from the Swinehart Herbarium to other institutions are accompanied by three copies of a loan agreement that outline the terms of the loan and a list of the specimens being sent. There are three copies of the loan form. One is for the records of the borrowing institution, one copy is to be signed by the borrower and returned to the Swinehart Herbarium to inform me that the loan was received in good order, and one copy is to be returned when the specimens are returned, and it will then be signed by me and sent to the borrower as a return voucher. Herbarium Specimen Labels. Perhaps the most important written document in the Herbarium is the specimen label. Below is the label in current use for specimens in the Swinehart Herbarium. Stamps. Regularly used, special stamps include: Accession No.: This is the accession number of the specimen. It is stamped both within the Accession Label on the lower left of a sheet and on the specimen label. While most herbaria do not include the accession number on the specimen label, I have begun this practice because I have encountered situations where a label gets detached and separated from the sheet due to failure in the adhesive over time. Having an accession number on both the sheet and the label allows the label (and its important data) to be returned to the proper sheet / specimen. Accession Label: This label is stamped either on specimen envelopes (in the case of mosses) or on the bottom left corner of vascular plant specimen sheets. The accession number of the respective specimen is placed next to the herbarium acronym within the box. Other stamps used in the Herbarium are the typical office type, including such things as “COPY”, “RECEIVED”, “ORIGINAL”, “DUPLICATE”, etc. PROCESSING PLANT SPECIMENS Collecting New Specimens Addition of specimens to the Swinehart Herbarium will involve plants associated with specific field studies as well as plants collected simply to add to the diversity of the collection. Collections from field studies are especially important. The flora of a local wetland for instance will tell future scientists much about natural succession as well as human disturbance/destruction. What and How to Collect. When a specimen is ready to be collected, several things need to be considered before the “harvest.” First, is it legal and/or ethical to take a specimen of a given species in a given location? Check with local laws about plant collecting on public and private land. Some species are protected by law, and regardless of the status, all plants and other natural features are protected in State Nature Preserves. Collecting permits are often granted for legitimate projects and requests. These may be solicited by writing the State Department of Natural Resources. However, even when collecting is legal, the collector must impose upon himself some personal standards. Some botanists will not take a specimen if less than six are present in a local area. Thirty is perhaps a safer number. Other considerations include proximity of similar sites with similar species, relative rarity of the plants, etc. The next consideration is which plant to collect. Some botanists mistakenly collect the biggest and best of a group. The problem with this practice is that instead of collecting a representative sample, an exceptional specimen is taken. Regardless of whether an individual has an unusually good habit or an unusually bad habit, it is still exceptional. Therefore, select an average specimen, representative of the group. Much is to be gained from this practice, as herbarium specimens can be of use to more than just taxonomic botanists. Plants damaged by fungi, insects, and other organisms tell much about the ecology of the system both spatially and temporally. Whenever possible, collect reproductive structures, flowers and or fruits, and roots. Once a plant has been selected, write down as much information about its situation as possible in a field notebook. Assign a collection number to the plant (preferably with a string and tag) and then collect the specimen. A trowel can be employed to acquire roots in addition to the obvious stem, leaves, and reproductive parts. Not all herbarium specimens will have roots, while these are not ideal, they are still worthwhile. Certainly, large, woody trees will not allow roots to be collected, but a carefully removed sample of the bark is not difficult to take. After the plant has been taken, it should be wrapped in moist newsprint and placed in a vasculum. A vasculum is a rigid metal, cylindrical container with a shoulder strap. It protects the specimens from being smashed, etc, and keeps them moist and unwilted. Some botanists use plastic bags to collect, but doing this in a marsh dominated by swamp rose (Rosa palustris) or other shrubs will result in a trail of specimens marking the path of a collector with a torn garbage sack. Pressing. Fresh, unwilted specimens are ready for immediate pressing. Wilted specimens will need to be soaked in water to soften the leaves and flowers. A press consists of blotters, newsprint, and supporting pieces of cardboard, sandwiched between two hardwood latices. Plants are placed in a folded piece of newsprint (preferably without ink, as this ink can rub-off on specimens) and arranged so that when flattened and mounted, as many key features as possible will be exposed. Some leaves should be facing up, others down. Tall specimens should be folded in an “N” shape to facilitate placement on a standard herbarium sheet (some large specimens will need to be broken and glued to more than one sheet). Specimen data should either be written on the newsprint, or included as a separate piece of paper with the plant. The specimen, now in a piece of folded newsprint, is placed between two blotters. About 10 specimens with blotters are sandwiched between pieces of cardboard (for support). As many as 50 plants, depending on their thickness, may be pressed at once. After the specimens, blotters and cardboard inserts have been placed between the wood lattices, the press is put under pressure by sitting on the apparatus and tightening the two straps. Most plants dry within about a week. Changing of blotters may be necessary on the third day. Processing New Specimens Drying. Presses full of fresh plants can be placed into a drying cabinet which accelerates drying. Both heaters and a fan contribute to the drying process. Presses should be set on end to facilitate escape of water vapor. Avoid high temperatures, as this will cause browning of the specimens. Decontamination. Eradication of prospective insect pests is conducted by deep-freezing the specimens. This is done after drying. Freezing before drying may damage internal structures of a specimen by means of ice-crystal formation. Most destructive insects in the herbarium are tropical, and all stages of their life cycles succumb quickly to freezing. Dried plants should be frozen for at least 24 hours before placement in the Herbarium. However, to insure that these and other pests do not endure and propagate in the herbarium, paradichlorobenzene tablets (moth balls) are placed in containers in each cabinet. This is the pleasant, familiar aroma that characterizes the Herbarium (note: paradichlorobenzine may have carcinogenic / mutagenic qualities. Other pest deterrents may be desirable for some). Mounting Specimens Types of Glue & Proper Application. Experience has shown that gluing specimens to the herbarium sheet is superior to other methods of attachment, at least in terms of durability. Several types of glues have been used in the past, but white glue has proven to be the best. Many herbaria use white wood glue, or the “Elmers” type, however, the best type of white glues are made especially for mounting plants. Most of these glues are flexible, water soluble, and reversible. The glue used by the Swinehart Herbarium is the Missouri Botanical Garden Type. This is a white, plasticized PVC resin that does not become brittle with age. The method of application is the “Glass Plate Method”. A quantity of glue is poured onto a plate of glass and an appropriate amount of water is added to the glue to reduce the viscosity to roughly the consistency of maple syrup. The glue is then spread out in a thin layer over the glass plate. At this point, an assembly line is established in the following order: un-mounted specimens, glass plate, herbarium paper, cardboard support, stacked supports with mounted specimens. The following procedure is conducted. 1. A specimen is removed from the newsprint folder and carefully placed on the glued plate (it is a good idea to make sure the plant will fit the herbarium sheet before gluing). 2. All portions of the plant are gently pushed into the glue with tweezers. 3. The plant is carefully removed from the glass plate and placed on an herbarium sheet. Make absolutely sure that there is enough room on the herbarium sheet in the lower right corner for the specimen label. Labels must be FREE AND CLEAR from the specimen. 4. Place any seeds or other loose fragments in a glasine envelope and glue or staple the envelope to the herbarium sheet, preferably above where the specimen label will be fixed. 5. Place the mounted specimen on the cardboard support. 6. Place several metal washers on the plant to assure attachment of the specimen to the paper. 7. Attach temporary label (scrap of paper with data) to the sheet with a paperclip. 8. Stack the cardboard supports/specimens (with wooden spacers) and let the glue dry for about 20 minutes before removing the weights for the next cycle. Specimen Arrangement. The main considerations in arranging specimens on a sheet are assuring visibility of important features of the plant and seeing to it that the plant does not exceed the margins of the sheet. There is also an artistic element in the way a plant is arranged. One does not just randomly place a specimen on a sheet, even if the above considerations are met. Bridson & Forman’s (1992) Herbarium Handbook is recommended reading for good information and illustrations relating to mounting specimens. Labeling: Typing, Attachment & Placement. Labels should be neatly typed or neatly written with permanent ink (insurance of archival quality) and without errors. Family name should be in ALL CAPITAL letters. Genus and species should be underlined. Examples of correctly written scientific names are: Sphagnum wulfianum Girg. (note that there is NO underline between genus and species) Sphagnum recurvum var.brevifolium (Lindberg ex Braithwaite) Warnstorf (note “var.” and authors names are NOT underlined) Sphagnum sp. (note “sp.” refers to an undetermined species in the singular sense. “spp.” is plural and would never be used on a normal herbarium specimen, because generally only one taxon is included per sheet or envelope. “sp.” and “spp.” are never underlined) Examples of incorrectly written scientific names inlcude: Sphagnum wulfianum Girg. (do NOT underline space between genus and species. Do NOT underline the author’s name(s)) Sphagnum recurvum var. brevifolium (Lindberg ex Braithwaite) Warnstorf (Do NOT underline “var.” or “forma”) Sphagnum sp. (Always underline genus and species) Climacium Americanum (Although Deam adamantly supported capitalization of proper specific epithets, it is not accepted by international codes of nomenclature). The “Notes:” on the specimen label was deliberately designed as a very general category, because the kind of data taken varies with investigator. Having a separate category for elevation, township and range, city, county, country, etc., would end up wasting space and appearing sloppy, because in many cases one or more of these data were not collected. The proper way of filling-out the notes section is to start with the most detailed aspect of the location and work up to the most general aspect of the location. Other details such as elevation and associated species can be included afterward. Example: South facing slope of the riparian zone of the Elkhart River, T35N., R6E., Sec. 2, Elkhart County, Indiana, U.S. A. Elevation: 804 ft. Growing among Impatiens capensis. Make sure to include county wherever possible (most state floras use the county as the smallest unit of distribution and range), and always include State and Country. While U.S.A. may be obvious to an American, a foreigner may have no idea what country Indiana is in. The collector’s name should be written out in entirety. The date should include up to the first four letters of the month, followed by the date and year. Examples: June 12, 1970 Aug. 15, 1984 Do not use numbers to represent months. It is too confusing because American and European sequences and notations are different (e.g. 1.2.97 means February 1, 1997, in Europe, and 1-2-97 means January 2, 1997, in America, etc., etc.). The determiner’s name should be written out if it is different from the collector’s name. If the collector determined the specimen, then only the initials of the collector are needed in the “Det:” category. Labels are attached with spray adhesive to the lower right corner of the herbarium sheet. Spray the label and then affix it to the sheet (not visa versa). There should be no more or no less than 3 mm of space between the edges of the label and the edge of the sheet. Labels should be straightly aligned, not crooked. Ordering Supplies. The Swinehart Herbarium orders most of its supplies from the Herbarium Supply Company, 3483 Edison Way, Menlo Park, California 94025, U.S.A. A catalogue of supplies may be obtained by written request. Accessioning Specimens Placement of Accession Numbers. An accession label is placed either on the specimen envelope (in the case of bryophytes, etc.) or on the lower left corner of the herbarium sheet. The accession number of the specimen is stamped in the box next to the acronym using a number stamp. Re-inking of the stamper should occur the night before the next accession, because the ink is viscous and takes time to absorb into the pad. In addition to placing an accession number on the sheet or envelope, there is also a space to stamp on the label itself. This is done in case the label ever becomes separated from the sheet. Having accession numbers on both will help in re-matching the label to the sheet/specimen. Record Keeping. Magnetic storage alone is not an acceptable means of record keeping. There MUST be some form of a “hard” copy to protect records from being erased and lost. Reliance on computers has resulted in sloppy record keeping. Accession numbers and specimen data are to be recorded in these volumes whenever new specimens are processed and added to the Herbarium. Make sure to include the date the specimen was accessioned when adding information to the record book. Record data neatly and cleanly. Follow the format of previous entries. Click on thumbnail for larger image Computer Database. Data recorded in the herbarium log are also entered into a computer database. The Swinehart Herbarium uses FileMaker Pro. Deposition of Specimens in the Herbarium. Once a specimen has been assigned an accession number and the appropriate record keeping has been conducted, the specimen is ready for decontamination and placement into the Herbarium. In the Swinehart Herbarium, there is an “in-process” folder. New specimens can be placed in this folder, and as several specimens begin to accumulate, they can be added to the respective locations in the herbarium stacks. This saves time and limits handling of specimens by reducing the number of trips to the stacks. Annotation Credibility of Annotations. Determining the credibility of someone's ability to reliably annotate a specimen is rather subjective. Generally, annotation of specimens from the Swinehart Herbarium should be conducted by professionals with demonstrated skill in taxonomic botany. This may include graduate students, professors, non-academic scientists, and exceptional undergraduate students and plant enthusiasts. The decision to grant authority to annotate specimens is at the discretion of the curator. Annotation Labels. An annotation label should be relatively inconspicuous and should not detract from the appearance of the sheet/specimen. In general, annotation labels should be limited in size to no larger than 5 x 10 cm. They may be placed above or beside the original specimen label or where space will allow if the former locations are not feasible. Annotation labels should include the name of the annotator, associated institution or project, date, and the full scientific name for which the specimen should be referred along with other pertinent notes. Placement of Annotated Specimens in the Herbarium. Assuming credible annotations, any specimen which is referred to a truly different taxon than previously labeled should be moved to the correct folder. Voucher Specimens and Exchanges The Swinehart Herbarium is an active collection. Properly identified voucher specimens (mounted or unmounted) associated with research projects and floral inventories are welcome. A small collection of plants for exchange programs with other herbaria is maintained. Trading or exchanging specimens with other herbaria is the most efficient way of increasing collections without travelling. Records of exchanges with other herbaria are kept. A standard loan form is used to document exchanges. Additionally, an exchange summary is kept for each herbarium for which exchange has occurred. CORRESPONDENCE The written correspondence of an herbarium is an extremely important and interesting aspect of herbarium operations. It represents an historical record of not only the herbarium and its scientists, but of plant taxonomy and scientific culture as well. Copies of all letters (including e-mail) sent out by the Swinehart Herbarium (especially those directly dealing with the Swinehart Herbarium and its daily procedures and exchanges) are placed in three-ring binders. Binders are stored in the curator’s office. |