Most people want to hold on to items with sentimental value, even flowers. Whether they were a gift from a coworker, friend, for Mother’s Day or from your significant other, flowers bring a joy that we want to make last. To preserve your beautiful blooms, as well as those special memories, try flower pressing.
We’ll show you how to properly press flowers, so that these important blooms can remain in your collection for many years.
- Picking the Right Flowers
- Paper to Use
- Ways to Press
- Label Examples
- Links to More Label Examples
- Make Your Own Herbarium Identification Book
- University of Florida Herbarium (FLAS)
- Making Good Specimens
- How to make a herbarium
Picking the Right Flowers
Freshness is the key. Choose flowers that are either still in bud form, or that are freshly bloomed. If you’re picking them from a garden, do so in the morning right after the dew has evaporated.
Once you have chosen the flowers you would like to press, they need to be prepped. If you can’t press them right away, place them in a ziplock bag and store them in the refrigerator. When you are ready to press, there are a few steps to take to ensure the flowers keep their color and freshness:
- To allow for maximum water absorption, hold the stems under water immediately after cutting. Then, recut the stems at an angle.
- Remove any leaves that will be below the waterline in the vase. If left on, those leaves will rot and can create bacteria that shortens the life of a flower.
- Place flowers in a clean vase with water and flower food, or a teaspoon of sugar. Keep them in a cool, ventilated place out of direct sunlight. You only need to hydrate your flowers for a few hours.
- One thing to note is that flowers with naturally flat faces are the easiest to press. To press thick flowers like orchids or roses, you should split them down the middle with scissors or a knife.
- Lay the flat face of the flower on your paper and you are ready to press.
Paper to Use
To press flowers, you must dry them out as quickly as possible to prevent browning. There are a number of different types of paper you can use to accomplish this, such as printer paper, flat cardboard, plain non-treated facial tissue or even non-corrugated coffee filters. Avoid paper towels, as many have textures that may end up imprinted on the petals.
Ways to Press
There are a few DIY options for pressing flowers, some requiring more materials than others. Experiment with each method to find the one that works best for you.
How to Use A Wooden Flower Press
Here’s how to make and use your own wooden flower press:
- Cut two pieces of plywood in 9-by-12-inch rectangles. Drill holes in each corner of the two boards; be sure they line up properly when stacked.
- Place the flower between the two pieces of paper, and much like a sandwich, layer it so that it is wood, paper, flower, paper, wood.
- Use wingnuts and bolts to tighten everything together. You’ll need to change the blotter sheets every four days or so (this helps prevent browning) and the flower will need to be pressed for three to four weeks.
You can buy a flower press from the store as well.
How to Press Flowers Using a Book
This is likely the most popular way to press flowers, as it is also the easiest. Choose the heaviest book you can find, such as a dictionary or phone book. The moisture being absorbed will cause the pages to wrinkle, so use a book you don’t mind damaging.
- Place the flower between two pieces of paper, and place them within the pages of the book. Depending on the size of the book, you can press multiple flowers at once. However, be sure to space them out so that the moisture from one flower doesn’t transfer to another.
- Use more books, or perhaps a brick, to weigh down the book once it is closed. Be sure not to disturb the arrangement of the flowers upon closing.
- Change the blotter sheets every few days here as well. After two to three weeks, the flowers will be completely dry. When removing, use a pair of tweezers, or very carefully use your fingers, as a completely dry flower is very delicate.
How to Press Flowers Using an Iron
If you don’t want to wait two to four weeks to complete your flower press, consider using an iron. As with all methods of pressing flowers, there are a few things to know first:
- Press the flowers between two absorbent pieces of paper, and then flatten with a heavy book.
- Make sure there is no water in the iron. The last thing you want to do is add moisture to the flower.
- Heat the iron on low. Once warm, press the iron on top of the upper sheet of paper for 10 to 15 seconds. You do not need to make a gliding motion the way you would when ironing a shirt. Wait for another 15 seconds until the paper has cooled, then repeat this process. Carefully lift the paper to check if the flower is stiff and dry.
How to Press Flowers Using a Microwave
Microwave presses are available for purchase, but you can easily make one yourself as well. Use two ceramic tiles and rubber bands to hold them together. You can microwave a book flower press, so long as the book doesn’t have any metal parts; yes, that includes little staples that may be holding the book together.
- When using a homemade press like ceramic tiles, line each side with a piece of cardboard and piece of paper. Place the flower in the middle and sandwich everything together.
- Using a low temperature (a high-heat setting can turn the flowers brown), heat for 30 to 60 seconds at a time, allowing everything to cool between each heat cycle.
- If you’re using books or have more than one ceramic press, save time and press multiple flowers by rotating one in while another cools.
- When the flowers are dry, complete the process by using the book method or traditional flower press. They should dry within two days.
Whether you grew them yourself or received them for a special occasion, the flowers that mean the most to you can remain in your collection for many years using any one of these pressing styles. And if you need new flowers to enjoy and then press, we’ve got a great selection from which to choose.
A voucher herbarium specimen is a pressed plant sample deposited for future reference. It supports research work and may be examined to verify the identity of the specific plant used in a study. A voucher specimen must be deposited in a recognized herbarium committed to long-term maintenance. More information on herbaria may be found in our web document “Herbaria and Herbarium Specimens.”
Why is voucher material needed? Plant classification is constantly changing. Shifts in species alignments and groupings are made as new evidence comes to light. Identifications are subject to change. Vouchers specimens help cross-reference these changes to previous research.
Preplanning for the preparation of voucher specimens is crucial. Arrangements should include:
- targeting collection locations and date periods to obtain useful specimens;
- obtaining collection permits from appropriate agencies (this can take months); and
- establishing official contact with government, herbarium, and research personnel in the area you will be working. This is required by law in most countries.
PRESSING AND DRYING PLANT SPECIMENS
Specimens are pressed in a plant press, which consists of a wooden frame (for rigidity), corrugated cardboard ventilators (to allow air to flow through the press), blotter paper (to absorb moisture), and folded paper, typically a newspaper (to contain the plant material). The plant press is tightened using straps with buckles or bolts with wing nuts. The objective of pressing plants is to extract moisture in the shortest period of time, while preserving the morphological integrity of the plant, and to yield material that can be readily mounted on herbarium paper (an acid-free cardstock) for long-term storage.
In order to fit on a standard herbarium sheet, a plant specimen should be pressed flat to no more than 11 X 16 inches. If the specimen will not fit those dimensions, it may be folded or cut into sections. Multiples of smaller plants may be pressed together in order to provide ample material for mounting and study. Small loose pieces, such as seeds, may need to be placed in a small paper packet inside of the newspaper. Large fruits or bulbs are often cut in half lengthwise or in slices prior to pressing. In order to insure rapid and thorough drying, extremely succulent materials such as cactus stems may need to be sliced open and some of the fleshy interior scraped out.
Each specimen should consist of a stem with attached leaves and, if at all possible, flowers and/or fruits. The roots of herbaceous plants should also be included. In the case of very large trees, shrubs, or vines, pieces should be selected to illustrate to the greatest extent possible the overall characteristics of the plant and the range of variation in flowers, leaves, and other structures. Each collection, i.e. gathering of a plant specimen, should be assigned a collection number. Data for each collection should be entered in a field notebook (see discussion of label data below) and the number should be written on the folded paper containing the specimen. Do not trust your memory for this information! If ample material is available, a minimum of three specimens should be pressed for each collection, especially if collecting in a region where the flora is poorly known. This will help facilitate the identification of the plants through the distribution of specimens to various herbaria and researchers. An ethical collector will insure that his/her collecting activities do not pose a significant threat to the survival of endangered species or habitats. Ethical herbaria will only accept legally collected specimens. See Florida Plant Collecting : Regulations and Permitting for some guidelines on collecting in Florida.
Care should be taken to make good specimens. Pressing material immediately upon collection results in the best specimens. Samples that are allowed to wilt prior to pressing will generally produce inferior specimens. Plants should be carefully arranged as they are placed in the press to maximize preservation of diagnostic features. Leaves, flowers, and fruits should be spread out so that they do not overlap and can be observed from different perspectives. The collection number should be clearly written on the outside of the folded paper containing each plant specimen. The plant press must be kept tight; this prevents shrinkage and wrinkling of the plant material and yields specimens that are easier to mount securely on herbarium paper. The pressed plants must also be thoroughly dried prior to storage and mounting. Best results are obtained with the use of an electric dryer that holds the presses and provides steady bottom heat between 95°F and 113°F (-120°F) (e.g., see Blanco et al., 2006 and the plant dryers and field presses section of the UF Herbarium Plant Specimen Collection and Pressing Bibliography). A low ambient humidity and good airflow around and through the presses also insures rapid and thorough drying of plant material. As the specimens dry, it may be necessary to further tighten the straps on the press to minimize shrinkage and wrinkling. Rapid drying promotes the best retention of plant color, but excessively high temperatures or long drying periods can result in blackened, discolored, and brittle specimens.
Mounting and storage of specimens require a considerable financial commitment in the form of archival materials, labor, and storage cabinets. Herbaria have the prerogative not to accept specimens if the cost of labor/materials for processing is excessive or if the quality of specimens or accompanying data is unsatisfactory. Due to differences in mounting methodologies and materials, most herbaria prefer not to accept already mounted specimens. Because plant classification is generally based on the morphology of flowers and fruits, in most cases sterile (non-flowering or -fruiting) specimens will not be accepted.
IDENTIFICATION OF PLANT SPECIMENS
The identification of plant specimens requires a considerable amount of time and effort. It is important to find out what research is being or has been done on the flora of the region where you are working. A thorough literature review and consultation with herbarium personnel will give you a good basis for starting the identification process.
The identification of unknown plant material is accomplished with the use of dichotomous keys; published plant descriptions, illustrations and photographs; and comparison with properly identified herbarium specimens. A microscope is essential for the observation of many diagnostic features.
Regulations pertaining to collecting plants vary from country to country and state to state, so it is important for you to make official contacts well in advance. It is customary and may be required to deposit one full set of specimens in a herbarium in the host state or country. A local herbarium is the ideal place to begin your quest for identifications, as its collection may be the most comprehensive for the region. It may be possible to arrange to identify your plants and receive assistance from staff members at this institution. But, one must realize that the identification of even relatively common plants may be time-consuming. Most institutions run on tight budgets and do not have staff available to assist or supervise visitors. Even if you are not able to identify your plants to species, you may be able to roughly group them by family or genus. This will allow you to seek experts in specific plant groups who may be willing to look at specimens in their purview. Experts in the flora you are working with may be interested in your collections and willing to give assistance. Your collections may, in fact, be helpful to their projects.
When submitting a plant specimen for identification, it is critical that the sample includes flowers and/or fruits and a portion of the stem with at least several leaves attached. Information of the plant’s growth habit, size, and the habitat where it is found (as well as any other features of the plant that may not be apparent from the sample, such as plant color or fragrance) often assist in the identification process. When submitting photos for identification include a general include full-frame close-ups of foliage as well as flowers or fruits. Be sure each photo includes a scale in the form of a ruler or coin. The photos should be accompanied by the same descriptive information provided with a pressed plant sample.
HERBARIUM SPECIMEN LABELS
A plant specimen is incomplete without label data. Label data is a form of field data and must be accurate. The following are important elements:
- Scientific name: genus, species, authority, infraspecific information
- Determiner of the scientific name: the name of the person who identified the plant
- Detailed location; the location is used by researchers on several levels:
- for general mapping to region, county or province;
- for detailed mapping, as in GIS computer applications;
- to physically locate the plant(s) in order to obtain further research material. The location should consist of: country, state or province, county or municipality and a description of the location in reference to roads, road junctions, mile markers and distances from cities and/or towns. Latitude and longitude, section, township and range, and elevation may also be helpful. A location taken with a Global Positioning System (GPS) is a desirable complement to the locality description. GPS coordinates MUST include a datum!
For more information see: Best Practices for Collecting Geographic Data in the Field
- Habitat: the type of plant community where the plant is growing and, if known, other plants growing in association
- Plant habit: describes the form of the plant (tree, shrub, vine, herb) and its height. Examples: tree, ca. 50 ft. tall. sprawling herb
- Frequency: is the plant rare, occasional, frequent or common?
- Plant description: describe characteristics of the plant which may be lost upon drying, such as flower/fruit color and fragrance, leaf orientation and aroma
- Collector name: it is recommended that the collector be consistent and use their full first name, middle initial (or full name) and full last name.
- Other collectors (*see label examples note below) present with the collector
- Collection number: a sequential straightforward numbering system (1,2, 3, …) is preferable.
- Date of collection: a format with the month spelled out or abbreviated and 4 digit year will prevent confusion. E.g., 3 May 2003, not 3/5/03 or 5/3/03.
* Please note, label formats vary considerably. We currently recommend that determiner be paired with the identification. There are two standards to denoted multiple collectors and a collection number. E.g.:
- David W. Hall #1946 with Chuck Nance and Allen Ake – where the collection number is know to be that of David W. Hall and may be cited as David W. Hall #1946 but is sometimes also cited as: David W. Hall, Chuck Nance and Allen Ake #1946.
- David W. Hall, Chuck Nance and Allen Ake #1946 – where the collection number is theoretically that of the first collector but the number could also be a team number. This should always be cited as: David W. Hall, Chuck Nance and Allen Ake #1946
POLK COUNTY: Just S. of Bartow city limits, ± ½ mi. E. of US 17, along S. side of Clear Springs Rd. 2 populations: ± 1800 ft. E. of railroad tracks and ± 45 ft. S. of center line of rd.; ± 400 ft. further E. and 95 ft. S. of center line. Flws. lt. purple; infrequent.
coll. David W. Hall # 1946 17 August 1993
Nandina domestica Thunb.
ALACHUA COUNTY: Gainesville, University of Florida campus, cultivated at south end of west side of Rolfs Hall. Cylindrical shrub, ca. 1 m. tall. Fruit bright red.
coll. Kent D. Perkins # 5555 12 Dec 1999
Artabotrys suaveolens Blume
Malaysia. Sabah. Tambunan District: Crocker Range, Km 64.5 on Kota Kinabalu – Tambunan Road. 5°46’N, 116°21’E. Elev. 1220 m. Montane dipterocarp forest. Crocker Formation. Woody climber on roadbank.
John H. Beaman 7178 9 October 1983
Universiti Kebangsaan Malaysia, Sabah Campus (UKMS)
Instituto Nacional de Pesquisas da Amazônia
The New York Botanical Garden
Rhabdodendron amaconicum (Spr. ex Benth.) Huber
Mun. Óbidos, Pará. 91 km de Oriximiná nos Campos de Ariramba, entre rio Jaramacaru e Igarapé Mutum. Aprox. 01°10’S, 55°35’W. Campina aberta, solo areno pedregoso.
C.A. Cid Ferreira, 9749 04 DEZ 1987
Plantas coletadas com apoio de ENGE-RIO e Mineração Rio Norte, com participação de C.A.C. Ferreira, C. Farney de Sá, G. Martinelli, E. Soares, C.D.A. Mota de E.F. Batista.
Links to More Label Examples
Specimens are frequently re-identified once the original label is prepared and/or the specimen has been mounted. These re-identifications are recorded on annotation slips. For more information on annotations, see: Annotation of Herbarium Specimens: Recommentations and Annotation of Type Specimens: Recommentations.
MOUNTING HERBARIUM SPECIMENS
Mounting is the process of affixing a dried pressed plant and its label to a sheet of heavy paper. This provides physical support that allows the specimen to be handled and stored with a minimum of damage.
Prior to attachment, the specimen and its label are laid out on the paper to allow maximum observation of diagnostic (usually reproductive) features as well as the range of variation in vegetative structures, including both sides of the leaves. Plants are generally positioned in a life-like arrangement (that is, with roots or lower stem toward the bottom of the sheet and flowers toward the top). When laying out the plant, be sure to leave space on the sheet for the specimen label, annotation labels, and institutional accession seal. A paper envelope or packet should also be attached to the sheet to contain any fragments of the specimen that break off over time. Once the optimum arrangement of the specimen has been determined, it is attached to the sheet using a combination of glue and strips of gummed linen cloth tape. Glue is used sparingly to attach the larger portions of the plant, such as stems, large leaves, and fruits. Gummed linen mounting strips are then applied to reinforce portions of the plant that might be torn loose as the specimen is used. Large or bulky items may need to be sewn onto the sheet with a sturdy linen thread. The objective is to secure the specimen firmly to the mounting paper, while leaving some pieces of the plant loose enough to be removed if necessary. Excessive applications of glue that embed flowers and seeds on the sheet may make it impossible to observe diagnostic features or to remove samples, thus rendering the specimen useless for scientific study. The best way to learn proper mounting procedures is through hands-on training and practice with a variety of plant specimens.
Because herbarium specimens are intended for long-term study and storage, it is critical that that all supplies used for mounting be both durable and archival. Archival denotes materials that are free of acids and other compounds that may cause them or the specimen to degrade or discolor over time. Consequently, the mounting paper, label paper, packet paper, ink, glue, mounting strips, and storage folders should all be acid free and designed for long-term stability.
The UF Herbarium Specimen Preparation Guide provides an illustrated step-by-step overview of the mounting methods used in the UF Herbarium.
WHERE TO GO FOR MORE INFORMATION
- Fairchild Tropical Garden Collecting Guide: http://www.virtualherbarium.org/collecting.htm
- Field Techniques Used by Missouri Botanical Garden: http://www.mobot.org/MOBOT/molib/fieldtechbook/welcome.shtml.
- Guide to Plant Collection and Identification by Jane M. Bowles, University of Western Ontario Herbarium (UWO), London, Ontario, Canada.
- Herbaria and Specimens: What are They? By Diana Horton of the extirpated University of Iowa Herbarium, which is now part of the Iowa State University Herbarium.
Make Your Own Herbarium Identification Book
Now that summer is finally here in my part of the country, most of the plants are leafed out and producing flowers and even some fruit already.
I’ve gone looking for black caps and black raspberries, and am finding them along with blackberries. And the blackberries come in 3-4 different species here. So how do I tell them apart? I’m creating an herbarium. An herbarium is an identification book that you can create from a collection of dried plants – it can be personalized to your tastes or area.
Why an Herbarium?
Identification books are great, but unless you have a hands-on guide, or someone to show you what the plants are, the books can have many photos or drawings that start to look very similar.
With an herbarium, you can take samples of the plants and find out what they are later. Or, if you are like me and have specific goals in mind, you can go looking for certain plants to put into your herbarium. This gives you a chance to look them up, take them to a nursery or Master Gardener, or maybe an herbalist who can give you and exact diagnosis.
Remember that some plants that look like one other can be good for you or poisonous, so be very sure in your identification. If you are unsure, always wash your hands well after collecting your plant matter and keep those species well away from those that are similar.
Preparing for Plant Collection
Before you get started collecting plant material, determine which types of plants you want to collect. I am making one with just mints, cultivated and wild, and another with wild plants of this region, both good and bad.
- Get your book ready. You can use a photo album with sticky pages and plastic overlay or a scrapbook that you can put laminated plants onto. My first book that I made when I was much younger was made from pressed and dried plants that were laid on clear plastic sticky sheets, like those for covering shelves. I then laid another sheet over the top and sandwiched them together. Then I cut around the plant and mounted it in my book.
- Once you decide what you want to do, then you can get your pages done. I’m going to use several native species, so I’ll find the information, compile it into a file, and hold it there until I’m ready for it. Then when I have the plants ready I can pull up a blank page in my computer, determine where my plant will go, and then put the text on the page around the plant. I can then laminate the entire thing.
- Get your collecting materials ready. This can be gloves (I use nitrile like these so there are no allergens that will come in contact with the plants), clippers or a knife, bags (such as zip top or other clear bags), and an old phone book. You can also get a portable flower press, but it’s not necessary. You’ll also want note paper and a few pens and maybe a good camera.
- Prepare a backpack with necessities. I would take sunscreen, insect spray, water, snacks, and baby wipes or something to clean up with. Pack clothing according to the weather and a small first aid kit. (Learn to make your own natural first aid kit to pack for the outing.)
Collecting the Plant Material
Certain plants, like plantain, jewelweed, yarrow, and chickweed, are easy for me to identify. But some plants, like the oak trees, are harder to tell apart. I pick some plants at the time they flower and some when they fruit. Still others look different when they first emerge than when they are adults. Jewelweed is a good example here. Whatever you collect, be sure to label it and possibly take a photo of the entire plant, maybe even including the area it grows in. There are several types of mountain mint that grow in several areas here. Some only grow in higher elevations and some prefer denser shade. Whatever the area, be sure to mark it down.
If you are unsure of a plant, as I was earlier this year with mugwort, take a specimen and press it and add your notes. You can identify it at a later time, or get help from an expert. I cut off about a foot of the top, being careful to protect the plant as much as I can. Then I place it between the pages of a phone book until I get home. This does several things: It keeps it safe while you are hiking, it starts the pressing process, and it also starts the drying process. You can slip your notes along side it on the same page so you don’t forget what it is.
If you are collecting potentially harmful plants, such as water hemlock, be sure to use gloves and wash well after collecting. Most people should not attempt this since there are species that can be harmful, but since there will be no consumption, it is relatively safe. If you are unsure, leave it alone.
Pressing the Plants
A very simple way to press your plants is to place them on clean paper and then place another sheet of clean paper on top. Then sandwich the whole thing with newspaper on both sides. This will absorb much of the moisture. You can switch out the clean paper and newspaper if necessary. You can do several plants at one time this way.
On the outsides, place two thin pieces of plywood and then several heavy rocks or bricks on top of that. (I used the end of my couch once!) After a few days to a week, check your plants. If they are dry, leave them a bit longer. Nothing spoils a good herbarium like mold from plants that are not dried thoroughly. Once they are dry, you can mount them and add your notes.
You can also buy a good flower press for this task. They can be quite expensive, but if you will be doing a lot of plants, it may be well worth the expense. Find one here on Amazon, or look around at Ebay and even Craigslist for deals.
Words of Caution
As with any outdoor activity, you need to be aware of your surroundings. I was looking at some Solomon’s Seal the other day when I came across a wide pipe. At the mouth of it was a coiled up rattlesnake. Had I not been aware, I could have been bitten.
You also need to watch out for harmful plants. Poison ivy is one of the worst to come in contact with, but there are many other plants that can irritate the skin.
Snakes and other creatures abound, such as spiders, mosquitoes, and chiggers. Be prepared by using insect repellent (learn to make homemade insect repellent) and carrying a snakebite kit (find one here).
Watch the weather as it can turn hot or cold quickly. Be sure you stop often to drink water, and when you need to use the “outdoor facilities,” be sure of where you are.
Respect other people’s property by not picking plants without permission and never pick on state or federal land unless it is permitted. I have seen Lady’s Slipper and Ginseng near me, but those plants are endangered. For plants like that, I use only photos.
Have you ever made an herbarium? If so, what tips can you share with the rest of the community?
University of Florida Herbarium (FLAS)
Specimen Preparation Guide (Plant Mounting)
Researchers in many fields of study utilize herbarium specimens. It takes considerable effort to collect, prepare and store these specimens. Plant collector’s may have hiked and camped for days to obtain the specimen you are mounting. The specimen must be pressed, dried, identified and have a label prepared. Plant mounting is one of the last steps in the long process. In some cases, there may be few specimens of the plant in existence. Therefore, each specimen should be treated with the utmost of care.
Our goal is to permanently preserve plant specimen collections for long-term study. Therefore, attention is given to insure that all materials used are archival and nothing done to the specimen will degrade its scientific qualities.
- Do not discard anything.
- Take great care not to mix up labels.
- ALWAYS ask questions or put the specimen aside if you do not know what to do.
- Never turn mounted specimens upside down.
- Do not eat or drink anything in the mounting room without express permission.
- Specimen preparation should have your undivided attention. Cell phones usage, including texting, is not compatible with plant mounting.
- Respect others working in the mounting room in regards to your conversations and radio music volume and selection.
Materials and Supplies
| Pressed Plant Specimen with typed label and, possibly, one or more annotation slips.
THE MOUNTING CABINET next to the door of the mounting room contains specimens to be mounted. Select the top stack of specimens under the “MOUNT” sign on the left side of the cabinet unless you have been given a special set to work with. Always close the cabinet door securely.
|THE PRESSED PLANT SPECIMEN will be in a folded paper cover, usually a newspaper, and should contain one or more typed labels. The specimens may also include slips with plant name changes (annotations), project titles and/or source institutional recognition. Beware, there may be scraps of paper that are not archival and extraneous notes that should not be mounted.|
Evaluate the Specimen
- Will the specimen fit on one herbarium sheet?
- Is the specimen particularly bulky? Is it suitable for mounting on our standard paper? Or, does it need one of our heavier sheets and/or folders, boxes.
- Does it have a label? If so, make sure the label is clearly printed on white paper stock. If the label is yellowed, test it with a pH test pen in an unnoticeable area on the back. Purple indicates acid-free paper which is ok. Yellow indicates acidic paper that will deteriorate over time. In most cases these labels will need to be photocopied onto acid-free paper. Such photocopies need to be dark with solid print.
- Are there enough labels? If the specimen needs more than one sheet, you may need additional labels. The original may be photocopied, or printed from the label file.
- Does the collector # and other label information match any information written on the folded paper containing the specimen?
Note: this information should be saved, see “Save information” below.
Arrange the Specimen
- Arrange the plant and label on the correct size of the mounting paper before gluing anything down!
- Labels are placed in the bottom right corner, unless unfeasible due to the shape of the specimen. Only deviate with special permission.
- Annotation slips with name changes go above or to the left of the label. Leave room around the label at the top and left for future annotation slips.
- Leave room for the accession stamp (seal) and barcode preferably at the top right of the sheet.
- Arrange the plant as realistically as possible. Roots or the lower part of the stem usually look better at the bottom of the sheet and flowers towards the top.
- Determine what is the “top” side of the pressed specimen. Usually more flowers or fruits will be evident on this side. Usually more leaves will show their upper side in this arrangement also. At least one frond of ferns specimens should be mounted spore side up.
- Make sure some leaves are bottom-side up. Turn some over if there are not any already pressed that way. A portion of a large single leaf should be cut and mounted with both sides showing, and best of all, a large leaf should be mounted only with cotton mounting tape.
- IMPORTANT: If flowers and fruits are obscured by other plant parts such as leaves try to manipulate the specimen so that those parts show. Also, spread out, bend and fold plant parts so there is less overlap.
- Loose pieces should be mounted so they are obviously separate. If you know where they fell off, you can mount them nearby, but, DO NOT fake the arrangements of parts.
Glue the Label and Annotations Slips
- Make sure your fingers are not dirty or the smudges will end up on the label and sheet.
- Paint a smooth, light coat of glue on the entire back side of the label. It should glisten. Start affixing the label from the bottom right corner of the label on the bottom left corner of the sheet. Smooth it down, making sure the bottom of the label is just off the bottom edge of the sheet, and rub it diagonally towards the upper left corner. Cover it with a paper towel and give it a good rub.
- Glue on the annotation slips, if any: Annotation slips go above or to the left of the label. Watch for labels which are in two parts; don’t mount the bottom part as if it were an annotation slip. Leave room around the label at the top and left for future annotation slips.
Glue the Plant Specimen (unless there are instructions to use only strips or sew the specimen)
- Some herbaria only use gummed cloth strips and sewing to affix the specimens to the sheet. If the specimen is suitable for this method, you may attach it that way. Unfortunately, the majority of specimens will shed too much material if only stripped down and will require some gluing.
- Paint dots of glue on the back of the plant with a paint brush or with the glue squeeze bottle. Use glue sparingly so that the critical plant parts, such as flowers and seeds, are not embedded in glue and rendered useless for scientific study.
- Each plant will need a different amount of glue. In general, put more glue along the stems, less glue on the leaves and the least glue on the flower and fruiting parts. Leaves should have a dot of glue at the upper 1/3, center and lower 1/3. Inflorescences should have glue mainly on the rachis, peduncles and/or pedicels (aka “stems”); use very little or no glue on the flowers.
Add Cotton Strips and Sew Bulky Stems
- Affix gummed cotton strips across a few places along the stems (especially at the bottom). Try not to obscure too much of the plant with strips. Do not put strips over flowers, flower petals or leaf tips. Cinch the strips tightly around stems. If a stem is bulky “sew” it to the sheet by poking a hole in the sheet on each side, threading cotton string on each side and and tying it on back. Cover the tied string with a gummed cloth strip section.
Add a Fragment Packet / Save Loose Pieces
- Put a fragment packet on EVERY sheet. Use a packet appropriate to the size of the plant parts that might fall off.
- Be sure to save ALL loose pieces and place them in the packet. If there are any loose pressed flowers, put them in a packet. If there are very many of these flowers, a few may be mounted on the sheet.
- Secure the packet with a plastic clip, if the packet is large or tends to flap open.
- How to Make a Fragment Packet
- CUT OFF AND SAVE ANY INFORMATION WRITTEN ON THE FOLDED PAPER CONTAINING THE SPECIMEN. Keep this with the specimen as it goes through the stacks.
Tips for Unusual Specimens
- Bark: Mount bark so the outer side shows. It is best to affix bark with cotton mounting tape or sewing rather than with glue, unless it won`t stay.
- Large, but mountable, plant parts: Unusually large stems and other plant parts should go to the right side of the paper, if possible. These parts should be secured with gummed cotton strips or sewed on with archival thread.
- Large, unmountable, plant parts: Large items which can’t be mounted should be tagged with the scientific name, collector name and number, date of coll., brief locality info (Country, State, County, etc.) and accession number. The mounted sheet(s) should indicate that parts of the specimen are unmounted (e.g., cone in box). Please ask the Collection Manager about the handling of such materials; they are usually boxed.
Stack the Mounted Specimens
- Stack the mounted specimens in a stack so that the glue will dry. The glue dries in 8 hours or less (overnight). The following sequence should be used in stacking the specimens (from bottom up): cardboard, mounted plant, wax paper, foam, cardboard, etc. The wax paper is used to prevent the wet glue from sticking to the foam and cardboard.
- If you have any questions about mounting a specimen, put it aside and ask!
Specimens are usually mounted only when they have labels. There are rare instances when specimens are mounted before the labels are prepared. Great care must be taken to make sure the correct collection numbers correlates with each specimen.
- Pencil the collection number as written on the paper the specimen is in on the bottom right corner of the herbarium sheet (where the label will go). Double check to make sure you have put the correct number.
- After mounting the plant cut out all the notes written on the paper the specimen is in. Place these notes in the packet on the sheet. The collection number must be one of these notes.
- Do not put the accession seal specimens which do not have labels.
- Label all stacks of specimens which do not have labels as to the collector, locality of the collections and/or set name.
Special instructions will be given for specimen repair. The following are usual guidelines:
- Packets should be added to sheets without them.
- Loose pieces known to be from the specimen on the sheet should be placed in packets.
- Mylar/cellophane packets should be removed and replaced with paper fragment packets. The contents or the whole packet should be placed in the paper packet.
- Old paper packets that are deteriorating and brittle should be replaced.
- Strips should be added to reinforce loose parts. Glue should be used sparingly especially if the paper is yellowing.
- Metal paperclips should be removed.
- Specimens are remounted on new paper on a case-by-case basis. This should be done only with permission from an collection staff member.
The practice of horticulture is often described as a combination of art and science. And the practice of pressing botanical specimens demonstrates this nicely, I think. Every plant species has its own essence, so to speak, and capturing that unique morphological integrity can be very satisfying. To do this, carefully select plants to illustrate as many characteristics as possible; for example, the fine roots of a bunchgrass or the rather stout culms of sedge add a lot to a composition. If possible, it’s nice to collect an extra flower or two to press separately, especially if stems or other plant parts are large and will dry more slowly than the flower.
Dried specimen of Fraxinus latifolia, Oregon ash, with mature and immature leaves, twigs, and fruit, a winged samara. Photo: Denise Kelly
When creating a composition, I lay the plant out on 11- by 15-inch heavy weight Strathmore watercolor paper, in a way that, to me, presents a classical representation of the species. Coaxing a leaf or twig just so can be done with forceps, pins, or painter’s tape: I tend to use anything at hand. Securing the piece in place with gummed linen tape can either be done at this stage or saved for final presentation on a clean sheet of mounting paper. This very much depends on how large and woody or moist the sample is. Very large specimens are best dried separately and then mounted once completely dry.
Top the botanical specimen with a clean sheet of blank newsprint or drawing paper and sandwich between several sheets of newspaper and two pieces of rigid cardboard. This holds everything in place and allows for air circulation and faster drying, which reduces the possibility of mildew and results in better color retention. At this point, a heavy weight is needed, (bricks, heavy books, a concrete stepping stone) or a plant press that can be cinched tight. A fan speeds the drying process, as does low humidity and warm temperatures (up to 95 degrees or so).
The first rule when collecting wild plants is to gain permission. Collect only a specimen or two, just enough, leaving plenty of plants to grow and thrive. Of course, collecting in your own garden is a fine way to practice the art as well. Even weeds can be beautifully pressed, elegantly shown below with a cousin of our ubiquitous lawn pest, the common dandelion.
Type specimen of Taraxacum reichlingii v. Soest (LUX 26313). National Museum of Natural History, Luxembourg. Photo: National Museum of Natural History, Luxembourg.
Once the specimen is dried and mounted, I like to leave room for an herbarium specimen type of label that includes the plant’s scientific name (genus, species, and infraspecies information), the collection date and location, and the collector’s name. (True botanical voucher specimens require much more detailed information.) The finished piece can be matted and framed for display or stored in a cool dry place; remember that the specimens themselves will be brittle and require careful handling.
Making Good Specimens
Now you can collect your plant and make your own specimens
Before you pick any part of any plant remember to consider:
- Do you have permission to collect in the area concerned? You should never collect in a National Park, Forest or Wilderness Area without permission from the authorities. For some areas you may also need a collecting permit.
- Are there are enough plants to justify your action? In general, follow the 1 in 20 rule – only take one if you can see 20 other good plants of the same kind. Weeds, particularly noxious weeds, can be collected without limit, but minimize the disruption you cause. Don’t leave holes in the ground.
- Do you have a good reason for killing or damaging the plant. Whether it is a good enough reason will vary with location.
Pick Your Specimen
Steps to good collecting
- Make detailed field notes for the area before collecting the plant.
- Collect a good specimen – all the parts needed for accurate identification. Because you probably do not know what these are, collect as many different parts of the plant as possible – leaves, flowers, twigs, fruit, seeds. For small herbaceous plants, collect the roots and either whole stems or tops and bottoms (leaf shape, size, and arrangement may vary from top to bottom).
- Attach a tag to your plants as you collect them. This really helps you remember which plant is which when you are identifying them. Give consecutive numbers to each plant you collect and use the same numbers in your field notebook and on your tag.
- Collect flower and fruit whenever possible – positive identification often requires both of these.
- For herbaceous plants, be sure that enough of the below-ground plants are available to show what sort of root system it has.
- Press your plants while they are fresh.
Preserve Your Specimen
There are two parts to preserving specimens: Pressing and Drying.
Well made specimens can be both valuable scientific resources and visually attractive. Try to do both, but recognize that some species will frustrate you. Some specimens will blacken soon after being collected, in others just the flower color changes, possibly from a vibrant red to a dull purple. Most species in the Logan region make good specimens, but remember –
No specimen can be made to look better after it has been pressed.
Press your plants while they are still fresh.
How to press good specimens:
- Clean off the mud from the roots.
- Lay the plant in the newsprint as you want it to look when dried. Take advantage of the space available, remembering that there will be a label attached in one corner. Show both sides of leaves and, if possible, expose the inner portions of a flower.
- Select the best material if the plant is too large to fit in the press. For trees and shrubs, a portion of a branch with leaves and flowers. If it flowers before leaves grow, look and see if there is not one branch that is slightly ahead of the rest. For herbaceous plants, the flowers and upper leaves and some portion of the underground parts. Remember to add to your field notes observations that you cannot preserve such as the plant height or whether it was a tree of shrub.
- Bend the stem or branch if it is too long to fit the paper. If you clip off portions of the branch, leave a stub so that people can see that you have done so.
- If the plants are small, the specimen should contain several individuals (only if the population is large enough to support collecting several).
- Add your specimen in its newsprint wrapping to your plant press and close the press tightly.
- Do not leave bits hanging out of the press. They will not get pressed and will probably be broken off.
It is important to tighten your press straps well for good pressing. This can be done more easily by using your foot to tighten the straps as demonstrated in this picture.
There are special techniques for pressing seaweeds and other water plants. Put the mounting paper in a pan of water and float the plant onto the paper. Most seaweeds will glue themselves to the paper and make very attractive specimens. Red algae are particularly beautiful when pressed. Place wax paper or plastic between the seaweed and the newsprint or the seaweed will glue itself to the newsprint.
Specimens look best if dried by having air move over them. This is why sheets of corrugated cardboard are used in the press. Put the whole press in a warm, airy place until the specimens are completely dried out. The air temperature should be no more than 100°F or thereabouts.
In Utah, driving down the road with the plant press on a roof rack is very effective for drying plants. Placing the press over a heating vent at home is also effective.
Identify Your Specimen
You might recognize your plant or be able to guess the name, someone else might even name it for you. However, it is always best to check the name by working it out using reference books and botanical keys. If you do not know the name of the plant then this is the best way to work it out.
An on-line identification resource for tropical and some temperate plants can be found at ARTEMIS.
Specimens can be identified years after they have been collected, but it best to identify them as soon as possible, while the fresh material you set aside for that purpose is still fresh. If you cannot identify them immediately, make labels for them, leaving the name blank and put the label in with the specimen.
Make A Label For Your Specimen
A label is attached to each mounted specimen. The one shown directly above was generated from a program in the Intermountain Herbarium. The one shown on the picture at the top of this page was prepared using a blank form and filled in by hand.
To prepare your own labels click on the blank label to the right and save the picture to your own computer. You can even arrange a few on a page in a word processing program. Print the label and add all the information you have in your notebook. Alternatively, click here to open a word file that you can save to your disk and then use.
For a free downloadable DOS program for making labels visit the University of Florida Herbarium.
Mount Your Specimen
You will probably want to make your specimens look nice and last well so you will need to mount your specimens.
Use glue, sticky tape or a needle and thread to attach each specimen to a clean sheet of thin cardboard or heavy mounting paper.
If you use standard sized paper you can store them in a loose-leaf binder for easy access.
The dried plant will be brittle so if it is properly dried, put your mounted specimen in a plastic or paper cover if you will be handling it often, or if it is to go on display.
Large herbaria need to ensure that their specimens will last for hundreds of years so they must use acid-free paper and special glues and inks that do not deteriorate.
Botanical Collections of Great Falls, Virginia is pleased to present an antique pressed botanical specimen page over a century old from the large two-volume herbarium of M.J.E Sicard who harvested the plants in the French countryside in the year 1900.
A herbarium (or herbier in French) is a collection of dried plant specimens preserved together in a book to be used as a reference, for research and study or for a keepsake of travels.
During our travels in France, we purchased Sicard’s wonderful two-volume herbarium and were fascinated by the age of these plants that were collected over 110 years ago, but can still be identified and many grow in our gardens today.
We also appreciated the aesthetic and antique look of these pages with the dried plant silhouetted against the grayish blue background, which we think would make unique décor hanging on your walls–with an interesting back story to tell.
Sicard hand-stitched each plant specimen onto one side of archival heavy blue paper which measures 9 inches wide and 12 inches tall. At the top right he numbered the page and at the bottom left he wrote the name of the plant.
We hope that you and generations to follow will appreciate and enjoy each of these unique pieces of nature.
Contact Us for special framed options:
We offer framed pages where the frames have been finished with eight layers of various colors with closed corner moldings. Our professional framer has utilized the finest archival boards and glass to insure the conservation of each botanical specimen. Please note that the botanical itself is intended to “float” on the archival paper to allow it to move freely on the aged paper. These framed pages are only available by contacting us directly.
How to make a herbarium
How to make a herbarium
- 1. DEPARTAMENT DE CIÈNCIES Biologia i Geologia How to make a Herbarium
- 2. Materials list for plant collecting: Plant press Plastic bags Garden secateurs & trowel Small note book & pencil Tags (optional) PLANT COLLECTING Plants chosen should be good representatives of the species and should contain all the essential features necessary for identification, i.e. leaves, stems, flowers & seeds (+ roots if suitably small and the plant is common and abundant). Collecting too many plant specimens during field trips is wasteful; it is recommended that you collect only about three samples of your chosen species to ensure you have adequate space in the plant press and sufficient time and attention to devote to each specimen. If very small plants are being collected then gather enough so that several small specimens can sufficiently fill three A3 mounting sheets – mounting one tiny specimen on a big sheet looks odd.
- 3. PLANT COLLECTING Preferably collect specimens in dry conditions, a good time being mid-morning, after the dew has dried but before the heat of the day causes plants to wilt. If specimens are at all wet or you need to wash soil off the roots then dry them carefully before pressing. Field notes must be recorded at the time of collection, noting the following: Date, collection number, location, habitat, habit, special characteristics. Use a pencil for these notes rather than a pen because any damp/wetness can cause ink to smudge and be unreadable. Attaching a numbered tag to each specimen can be a very useful option as the tag number will link to the number in your note book, avoiding any later confusion. This is especially important if you are not certain of identification or are collecting several plants species.
- 4. PLANT COLLECTING Rare plants – of course permission is needed from the landowner before collecting any plants, but you also need to check if a plant is rare. Check out these links: <http://premsa.gencat.cat/pres_fsvp/AppJava/notapremsavw/59894/ca/37-especies-plantes- perill-critic-dextincio-catalunya.do> <http://herbarivirtual.uib.es/cat-ub/caracteristica/quadre_47.html> Transporting your plants home can be difficult and whilst plastic bags are good for collecting robust plants, delicate structures such as flowers can be damaged. To help prevent this you can blow air into the bag and seal it – this will help to cushion the plants and also provide some moisture. If the journey is lengthy you could also add a tiny amount of water to the bag or wrap the roots in wet tissues or cloths. If the specimens are slightly wilted when you get home you could place the roots/stems in water to revive them first before pressing. You can take newspapers, corrugated card and string with you – your plants can be placed between sheets of newspaper and an outer layer of card, and tied securely for protection on the journey. Finer plant position adjustments can be done later at home.
- 5. IDENTIFICATION You can use plant guides to help you identifying the specimens. Here you can find some useful links: <http://argus.biblioteques.gencat.cat/iii/encore/search/C__Sguia%20de%20plantes__O rightresult__U1?lang=cat&suite=pearl> <http://www.rjb.csic.es/jardinbotanico/jardin/index.php?Pag=594&len= > <http://www.keytonature.eu/wiki/Pautas_para_la_identificaci%C3%B3n>
- 6. PRESSING & DRYING Materials list for initial pressing: Plant press Newspaper A home made press is easy to construct from two sturdy pieces of A3 sized plywood and either two lengths of strap with buckles that can be cinched tight, or else four wing nuts & bolts at each corner that can be screwed tight.
- 7. PRESSING & DRYING Materials list for initial pressing: Plant press Newspaper A home made press is easy to construct from two sturdy pieces of A3 sized plywood and either two lengths of strap with buckles that can be cinched tight, or else four wing nuts & bolts at each corner that can be screwed tight.
- 8. PRESSING & DRYING Arrange the plant carefully, trying to avoid overlapping. If too crowded, either fold or trim some shoots or leaves. If trimmed, it is important that you leave a stub to show what has been removed. Large plants can have their stems folded to accommodate them within the confines of the page or you can have several sheets for one plant showing the top, middle and bottom of a plant. Specimens can be adjusted once they are partially pressed as this makes fine adjustments easier. This first adjustment could be after just half an hour of pressing with delicate plants, or perhaps the next morning with more robust plants. At least one leaf and one flower should be turn to expose the back surface. Important note: If the specimen has thick or lumpy parts, use folds of newspaper to add padding over less bulky structures to help distribute the pressure evenly. If this is not done, delicate leaves and flowers may receive insufficient pressure and end up wrinkled and discolored.
- 9. PRESSING & DRYING Succulent or fleshy plants may be cut longitudinally and/or transversely and it may be necessary to scoop out the inner tissue. Succulent plants can be killed by placing in boiling water for a few minutes or they may continue to grow and have even been known to send out a flower suddenly after years sitting in a herbarium! Bulbs and thick roots may be cut in half lengthwise (off-centre to prevent the plant from falling apart). For the first two to four days you will need to check daily and change the blotting paper and/or other surrounding papers, and retighten the press, but as the plants dry these checks can become less frequent.
- 10. PRESSING & DRYING If drying thick or fleshy material, change the sheets of drying paper more often but if you are not experienced then it is best to avoid very succulent material. They are very difficult to dry completely and if mounted moist are liable to become discoloured and smelly. Note: if your specimens are not completely dry, mould may develop on them and this can be very dangerous if you breathe in the spoors. Warmth may be used to improve the drying rate, for example over a radiator or in an airing cupboard (in a humid climate, heat is essential). The rate of drying is dependant on the plant material being pressed and the temperature, pressure and the paper used. Drying may occur within two to four days but often takes somewhat longer. Quick drying is preferred as it helps retain the natural colours and prevents decay and mould formation
- 11. MOUNTING Materials list for mounting plants: Cartridge Paper Waters-soluble glue or glue tape Computer-generated labels Cartridge paper for mounting your specimens should preferably be A3 size (the size required by official herbariums). Jagged edges look very messy and unprofessional – careful use a ruler and a hobby knife with a fresh blade, as this will produce clean, straight edges. Using only one side of your thick A3 cartridge paper, arrange your specimens carefully, making sure that they represent the way the plant grows naturally. Don’t try to arrange flowering stems artistically in a separate fashion. Remember you are aiming to show the viewer what the plant looked like in nature.
- 12. MOUNTING Loose specimens such as seed pods, pieces of bark, flowers and leaves should be placed in a small paper packet that is then fixed to the mounting sheet. These paper packets should only be folded and not glued or stapled together as one has to be able to open them out flat in order to access delicate specimens easily without damaging them. The specimens may be mounted directly on the paper with water-soluble glue. Apply as a series of small dots to the back of the plant parts. Water-soluble glue allows for later removal of samples if required. Alternatively, specimens may be secured with thin strips of paper or sown on with linen or cotton thread but these methods are not as popular because specimens can more easily detach and become damaged.
- 13. MOUNTING Specimens must be correctly identified and labelled: Example Herbarium Label : Scientific name: Ranunulaceae, Ranunculus ficaria (family, genus and species) Vernacular name(s): Gatassa (Cat.), celidonia menor (Spa.), Lesser Celandine (Eng.) Collector’s name: Vicent Ramiro Date of collection: 25th April 2016 Locality: Montsianell, Amposta Habitat: Damp, clay soil, 20 yards from riverbank, growing in dappled shade on the edge of deciduous woodland; nearby plant is Dock (Rumex obtusifolius). Habit: Perennial herb, up to 20 cm tall, with stems creeping and rooting Characteristics: Leaves hairless glossy green, flowers bright glossy yellow, turning white with age Medicinal uses: Astringent for haemorrhoids
- 14. MOUNTING It is recommended that you design a label using your computer. This may then be used a template for all other herbarium specimens. Giving clear borders around your label allows for much neater cutting and presentation. Don’t forget that characteristics are very important as they relate to all the extra signs that may be missing when a plant has been dried. Examples are: Colour & aroma Surface hairs Stem structure Exudate … Storage of collection: Storage is in a large A3 paper or card folder, with members of each genus being kept together. These folders are stored flat.
- 15. I hope this information is helpful – good luck and get collecting! <https://theherbarium.wordpress.com/2010/09/10/how-to-make-a-herbarium/> DEPARTAMENT DE CIÈNCIES Biologia i Geologia