Collecting specimens
Collect several specimens, supplemented by photos of the plant in its habitat if possible. Ease the plants from the soil by digging around them leaving roots or other underground parts intact. Try not to pull the plant from the soil.
Collection details
Take notes and collect information about the size and habitat of the plant. These will depend to some extent on plant type but generally, as well as leaves, it can be important to supply flowering parts, seeds and/or seed pods. Identification of perennial species will often require underground parts such as rhizomes or corms to be included. Remember some plants have separate male and female flowers, in which case it is necessary to collect both sets of flowers. Note the flower colour as this will change as the specimens dry out.
- For grasses, sedges and small plants include roots, basal leaves, flowers and fruits. Always include underground parts such as rhizomes, corms, tubers, and bulbs if present.
- For larger plants such as shrubs and trees collect a portion of stem that shows the branching pattern, preferably with flowers and fruits. If flowers and fruits are not present on the same stems, collect several samples. Record the dimensions of the plant and for trees, note the trunk diameter
- In both cases note details of collection such as date, time, and collector. A general description of habitat and circumstances will also be useful, as will details of any soil analysis in the vicinity.
Specimen preparation
All specimens should be free of soil. Gently wash the roots to remove wet soil. Hard-set soil may need to be soaked off to prevent damage to the roots. Large plants such as tussock grasses and sedges can be carefully pried apart and a few tillers with seed heads can be kept for identification. Preparation can be minimal for short term identification or more involved for long term storage;
- Short term: put plants and/or plant parts in a plastic bag with a few millilitres of water with roots toward the bottom of the bag. Have plants tagged with specimen number, date, collector and locality. Writing on the bag with waterproof pen often rubs off, so it is preferable to have a written label in the bag. Tie-off the top of the bag. This will maintain humidity and help keep the specimens fresh. Keep the specimens out of the sun. Most specimens can be kept in a refrigerator for a few days. The main exception would be specimens with large, soft flowers.
- Long term: place the specimens between several sheets of newspaper. Arrange the samples so that leaflets/leaves and flowers can be clearly seen. Larger specimens can be bent into a zigzag to fit the sheet. Multiple samples in newspaper can be laid upon each other. These are then placed between rigid boards with weights such as bricks or books supplying pressure to flatten the specimens. Change the newspaper daily for the first few days then weekly until the specimens are dry.
Sending specimens to the herbarium
Keep the specimens between sheets of newspaper. Insert a sheet with all the collection details, such as the one attached, and place between 2 pieces of firm cardboard. Local museums, wildlife trusts or FWAG group will probably have an expert, or know where to find one, in order to get your weed identified. Attach a covering letter outlining your request for identification (and address for correspondence!).
Further research information / Links:>>collecting specimens<<
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