Collecting techniques

When you need to confirm a rare or protected species, photograph the plant and make a good written description and/or sketch. Take several close-up shots (with a ruler or other object for scale) showing the plant and parts necessary for positive identification.

Determine the amount of plant material you require, select a variety of individual plants for collection, then begin the actual collection of the specimens

Basic techniques

Select specimens in good condition, free of insect damage, rust, or disease.
Select plants with mature parts (well-developed leaves, stems, roots, flowers, and/or fruits or other reproductive structures).
Select specimens that represent the range of variation in the population, not just atypical specimens.
Collect entire plants when possible, even if they are large (the plant can be divided for pressing).
Collect enough plant material from each species to fill two standard herbarium sheets (30 × 42 cm) (see Figure 1).
Collect at least stems, leaves, and flowers or fruit of herbaceous plants, and twigs, leaves, and flowers or catkins of trees and shrubs.
Collect extra flowers and fruit for later dissection.
Retain as much of the root system as possible. Remove excess soil as it may cause disfiguration and deterioration of some plants.
Place all specimens of a single species from one locality into one collection bag.
As each specimen is collected, assign a unique collection number

For aquatic specimens

Many aquatic plants are extremely fragile and readily break apart after removal from water. Handle them carefully at all times.

Some characteristics useful for identification are destroyed by handling and subsequent pressing. Learn these characteristics and record the information immediately, for example, a cross-section of Nuphar petioles.

Seal the holding containers properly to prevent leakage or loss of specimens or parts in transit.

Protection in the field

Specimens should be pressed in the field whenever possible (usually after returning to camp in the evening, and preferably daily) because delay causes a significant difference in the final result. If not pressed immediately, some delicate species like Campanula rapidly lose their colour and structure, and some Asteraceae petals and

heads curl.

However, in field sampling it may be several days before specimens can be pressed. Most plants will remain in reasonable condition for up to a week if handled properly and kept cool and moist. Watch the bagged plants closely for signs of deterioration. Follow these suggestions to keep unpressed plants fresh:

Expel excess air from large plastic bags and seal.
Keep collection bags in a cool place, near a stream, in the shade, or in a cooler.
Sprinkle fresh water into the bags during hot weather, or add a moistened paper towel.
Shake off excess moisture or ‘‘blot’’ plants collected in the early morning or during wet weather.

Recording the Data

A plant collection without accompanying data is of no use to the scientific community. Keep a careful record of collection data and field observations in a field notebook using a consistent, clear, and legible style. You can use the information later for the herbarium label or for preparing a collection report.

File the completed field notebook as a permanent record.

The type of data recorded will depend on the collection. It usually includes collection number, date, name(s) of collector(s), location (latitude and longitude or northing and easting) and habitat information (elevation, water depth [for aquatic plants], slope, aspect, soil, moisture regime, associated vegetation, and biogeoclimatic zone and/or subzone). Observations about each plant species collected (e.g., flower colour, diameter, height, abundance, odour) should be recorded.

To reduce the amount of writing needed in the field book and on labels, collect as many different plants as possible from the same site. Write the information common to all specimens (collector, slope, aspect, associated vegetation, etc.) at the top of the page, then list collection numbers with brief identifying information. Some collectors have a stamp made with standard headings to stamp directly onto the notebook page. More detailed information can then be filled in as the plant collection is made.

Write legibly so that time is not wasted by someone trying to interpret your field notes. Notebook computers may, in the future, obviate the need for field books, but collecting can be wet, dirty work and they may not stand up to these conditions.

Collection number

As soon as the specimen is bagged, record a collection number in the field notebook. Write the collection number on a waterproof tag and place it in the bag with the specimens, or label the outside of the bag using a permanent marking pen. If you are pressing right away, you can write the collection number on the flimsy (newsprint folder) in a corner or along the border. The collection number makes it easy to reference individual specimens or groups of specimens in a collection.

Several numbering systems are in use, as follows:

Some taxonomists assign collection numbers to specimens sequentially throughout their careers (up to six digits may be used), and can, therefore, use a rotating number stamp directly on the pressing paper. This method allows researchers to identify when in a taxonomist’s career the plant was collected, to track the specimen from a published account, or to calculate the total number of specimens collected.
Some collectors assign field numbers by year. The number consists of the last two digits of the collection year, a dash, then a sequential specimen number. For example, the first plant collected in 1991 would be 91-01,then, 91-02, and so on. This method is useful if the collector will return to the same area over a number of years, or for an organization that produces annual reports. It gives an immediate indication of when the specimen was collected. However, with the approach of the end of the century, this system may cause confusion (was 01−45 collected in 1901 or 2001?).

Another system may be needed.

For collections made during a vegetation or ecosystem classification project, collectors often use a project or locality abbreviation, followed by a plot number, a dash, and the specimen number. Each plant collected

has a unique number, but is also immediately identified by sample site or plot and project. For example, on the Toby Creek project (TC) plot number 401, the first specimen is TC401-1, the second TC401-2, etc.

In all the numbering systems, plants of the same species collected at the same sampling site or plot are given the same number. For example, if 10 specimens of Viola sempervirens (enough to fill two herbarium sheets) are collected from site TC401, then all 10 plants receive the same collection number (e.g., TC401-3). An exception would be if the specimens are of different trees of the same species in the same area. In that case, separate

specimen numbers would be assigned.

Date of collection

To avoid confusion, write the date in full (August 7, 1991). Note that ‘‘8/07/91’’ could be interpreted as August 7,1991 or July 8, 1991.

Name(s) of collector(s)

Record all significant members of the collecting party. In the future, if one collector is unavailable to answer questions, the others may be contacted. First initial(s) plus the last name is sufficient.

Location information

Provide enough information so that another person can follow the directions to the general area to observe more specimens of the same species. Use a good topographic map to determine latitude and longitude to the nearest 10 seconds, or the UTM co-ordinates, which are increasingly used in Geographic Information Systems (GIS)

Habitat information

Elevation: the vertical distance above sea level in metres; read from a topographical map, or use an altimeter.

Slope: the gradient of the site where the collection was made; measure using a clinometer. For example, a 50% slope would be 45^o.

Aspect: the exposure or orientation of the slope; measure using a compass bearing (remember to allow for magnetic declination).

Associated vegetation: a short list of other dominant species in the plant community being sampled.

Biogeoclimatic zone/subzone: zone, subzone and, if possible, site series.

Soil: type of soil encountered. You may want to be specific or not, depending on the purpose of the collection (see the Canadian System of Soil Classification). For example, coarse-, medium-, or fine-textured; soil depth, sand, loam, silt, clay, peat.

Moisture regime: the degree of wetness or dryness (xeric, mesic, hygric, hydric).

Water depth: for aquatic plants, note the depth at which they are rooted. Note whether the current water level is above or below the low or high water marks on the shore, and by how much. (If possible, note also the annual fluctuation in water level from low to high water marks.) Record if the plant reaches the surface, and what parts (if any) are emergent

Comments You may want to make specific notes to help with later identification. Some important observations are: For herbaceous plants

A record of the abundance of the species is important for the recordsof rare species kept by the B.C. Conservation Data Centre in Victoria.
Record the area covered in square meters, or estimate the number of plants if there are only a few.
Flower and fruit (e.g., berries) colour may fade or change after collection—especially blues and purples—so record the fresh colour in your notes.
Note the presence or absence of milky juice in plant stems.
Note any flower or leaf fragrances, or any distinctive odors when the plant is bruised

For trees and shrubs

The height and growth form (i.e., spreading, scraggly, columnar) may help distinguish between species of the same genus. This information is essential when the whole plant is not collected.
Flower and fruit colour for flowering trees or shrubs.

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