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Forest Plot



Vascular Flora of Wisconsin - Botany 401
Spring 2020

Forest Plot Information (pdf) & Specimen Label Template (Word or fillable pdf)

Choose a forest site, as pristine as possible, for your study. To avoid problems, try to locate forest site up to 20 acres for which you can get permission (friend, relative, etc.) to enter and collect a representative plant for each (non-rare) species that have adequate population sizes. Dane County or surrounding counties would be preferred (see the instructor if your site is further away). Working in groups of up to about four is helpful for both finding a site (if you are not from around this area) and car pooling. You will be required to recognize on site certain plant species that grow in your approximately 20 acre study site. This means that you should be able to provide the scientific name, the family name, and a common name for the plants. Species that you should know include all angiosperms that come into flower before the final exam, all trees and shrubs whether they flower or not, and the ferns, lycopods, and horsetails that are producing spores. You can work singly or in small groups. If small group then there should be one collection handed in, but each person will be asked to indicate how much effort they put into the collection. The deadline for picking a site (and letting your lab instructor know) is March 11 or 12 before Spring Break – preferably sooner as some trees and herbs may already be flowering.

This collection of dried, pressed, identified, and fully labeled plant specimens is due at the end of the semester and is required to pass the course. Your lab instructor will grade the collection on the basis of (1) completeness of sampling for species in your site, (2) correctness of identification, (3) proper preparation of material (presence of flowers, fruits, or other reproductive parts; representative leaves, stems, and roots if possible; pressing; and drying); (4) adequate labeling; and (5) mounting of 4 specimens (check with TA on what species should be mounted; previously collected specimens but unmounted by former students may be substituted for mounting as necessary).


Do not collect in city, county, or state parks and other designated natural areas. Do not collect in the University of Wisconsin Arboretum. Collecting in these places require special permits, without which fines can be issued. Practice plant conservation in your collecting! Do not dig up entire plants, especially if you are unsure of whether the species is rare, endangered, or threatened. Become acquainted with the DNR publication (available in lab) that lists these plant species. Be careful of plants in certain communities under current stewardship or study (most prairies, including roadside remnants).

Collecting the Plants

1. Plants should be collected in flower or fruit (or other reproductive parts for non-flowering plants). Specimens without these reproductive organs are termed "sterile", and are not usually worth collecting.
2. For small herbs, the entire plant should be collected, including the underground parts. For large herbs, a portion of the underground parts, a part of the stem with attached leaves, plus the inflorescence can make up the sample.
3. For woody plants, branches or twigs bearing leaves and flowers (or fruits or cones) are sampled. Leaves should be padded with extra paper so that the large twigs do not cause the leaves to curl while drying due to air-pockets in the press.
4. Collections should be plentiful enough to nearly fill a folded newspaper sheet (except for small plants that are rare at the place where they were collected; in such cases this should be explained on your label). The leaves and other plant organs should be spread out, before drying, to form a single layer as much as possible.

Constructing the Plant Press

1. The plant press is constructed out of 2 sheets of plywood (12 X 18 inches) as backing, layers of corrugated cardboard (corrugations run cross-wise not lengthwise), and one or two layers of blotters between cardboard. The press is kept tightly closed by two straps or ropes.
2. The plants are pressed within folded newspapers which are individually placed between two blotters or between a blotter and cardboard if only one layer of blotters is used. The newspaper must be small enough to fit within the plywood backing and cardboard layers. Ideally, one torn sheet of newspaper (ca 23 X 14 inches) is folded in half crosswise (11 X 14 inches). Pressing plants within these dimensions will insure that the dried plants can be later mounted on the standard herbarium sheets.
3. Presses will be supplied to each student and must be returned to the lab instructor when the collection is handed in.

Pressing Procedures

1. Plants can be collected in the field, trimmed to the appropriate size, immediately pressed in newspaper, placed between the two rigid ends of a plant press, and securely tightened. This "field press" can simply consist of the end boards and precut newspaper sheet. Later the sheets can be placed within blotters and properly dried. Alternatively, the plants can be placed in bags and pressed later. Some plants will quickly drop their petals or wilt so care must be taken that these plants are pressed soon.
2. Roots should be cleaned and free of excess dirt before they are put into the press.
3. Unwanted parts, dead leaves, extra roots or leaves, etc., should be trimmed off before pressing.
4. Plant parts should be arranged so there is as little overlap as possible; stems should be bent sharply and neatly to fit in the paper, not curved or twisted.
5. Plants should not be layered or massed together within the newspaper. If the plant is too large to place in a single fold of newspaper, the plant my be divided into 2 or more sections, each pressed separately and indicated with the collection number and the phrase "1 of 2" or "2 of 2", etc.
6. A field notebook should be kept, in which all collections are numbered and all locality data and other notes are written down. Your name and the collection number for each plant should be written, as well, on the front edge of the newspaper sheet in which it is pressed.

Drying Procedures

It is important that the specimens be thoroughly dried but not burned. This can be done by placing the plant press over a heat source: heater vent, fan-driven space heater, radiator, light bulbs, etc. Driers are provided in the lab. Succulent or wet specimens should have the blotters changed as needed to prevent molding. Press straps should be tightened from time to time during the drying process, to keep specimens from wrinkling.

Labels (template available here:
Word or fillable pdf)

Notes should be taken in a field notebook at the time the collection is made (not done from memory, days later at home). Each plant specimen (that is, a particular species collected at a given time and place) is given a separate number in the book. This field information is later transferred to labels that are handed in with the specimens. Labels must be produced using the available template labels on the lab computers and printed off.

Locality: Designate this by county and site, accurately enough so that someone else could find the exact place later. This can be expressed by mileage along a highway, distance from a town or from some geographical feature like a hill or lake. Township, range, and section are mandatory (townships maps for Wisconsin are available in lab).

Habitat: Designate this is general terms, describing the nature of the site where the plant grew. Examples are: roadside banks, open pasture, boggy meadow, shrubby thicket, shaded woods, rock slide, river bank, cliff, sand dune, etc. Important factors in plant distribution are the amount of light at the site, available moisture, nature of the soil, density of other plant growth, steepness of slope, etc.

Species name: The correct name (according to UW Herbarium website) should include the genus, specific epithet, and authority. The family name should be included on the top. Thus, identification of the species can use Gleason & Cronquist, Spring Flora, Michigan Flora, Peterson Guides, etc., but final name of the species must be checked with the UW Checklist online (it will list all other names or synonyms along with the accepted name).

Other necessary data: Designate the form of the plant (herb, shrub, tree, height, etc.) if this cannot be determined from the specimen. Give the original flower color. Optional information includes the names of other species growing with the this one, the soil type, the plant community, abundance of the species. The date of the collection, and your name and collection number are mandatory.

Example of a typical label:

Oenothera clelandii Wagner
WISCONSIN, Iowa Co. Dry prairie along RR track, N
of Helena, 3/4 mi. N on Hwy C from Hwy 14.

43°10'23.99"N 90° 1'17.05"W
T8N, R4E, N 1/4 Sec 16

Scattered individuals, to 1 m high, corolla yellow.
Growing with Froelichia floridana, Desmodium sp.

21 Sept 1985 Sytsma 5013

Collection report

A report must accompany your plant collection. This should include a description of the site (geographical location, vegetation type, disturbance) and a list of species (with family and common name) in the collection. Other species noted but not collected (not in flower, large trees) should be included in the description.

Handing in the plant collection (during exam week)

Each specimen is kept in its original pressing paper (or put into a clean new paper), the finished label is inserted loose along with the specimen and the collection ordered alphabetically by family. You must mount at least 3 specimens – more information will be given by your lab instructor. On the outside of the bundle, under the string, place your report. Never put tape or glue on your specimens or newspapers. Also, you must return your press.


Plant Collection Checklist

____ Collection Report: including a description of the site (geographical location, vegetation type, disturbance), and other species noted but not collected (not in flower, large trees).
____ Cover sheet: a list of all plants in collection, including families and collection numbers.
____ Folder containing all specimens
____ Mounted specimens: three plants must be mounted per student. So if your group has four people, there should be 12 mounted specimens on top inside the folder **.
____ Clearly numbered newspapers containing the remaining, unmounted specimens. Inside each newspaper should be one loose specimen and its accompanying label.

Notes about labels

Each and every specimen, mounted or not, MUST have a completely-filled-out label. For mounted specimens, these will be glued to the lower right-hand corner of the herbarium sheet. For unmounted specimens, the labels should be placed loose inside each folded newspaper.

** When filling out labels, the names of all members of your group should be included where it asks for collector name. ON THE MOUNTED SPECIMENS ONLY: the individual responsible for that particular mounted plant should have their name first. You will be graded individually on the quality of your mounted specimens, and we will only know which specimens are yours if your name is first on the label. Name order doesn’t matter for the unmounted specimens.

Desirable tools and equipment for collecting plants

Hand-lens or pocket magnifier; about 10X
Small pocket knife and/or pruning shears
Trowel or hand-pick (for digging up underground parts)
Large plastic freezer or garbage bags
Field notebook and pencils
Plant press, including newspapers and corrugated cardboard
Field manuals for plant identification