Collecting Plants

Collecting Plants

A good pressed plant will retain much of its colour and lie flat for many years. The secret to this is rapid drying without high temperatures. A plant press holds the plant flat while absorbent layers take up the water.

Constructing a plant press
To construct a plant press, gather blotters or newspapers, sheets of corrugated cardboard such as cartons, two rigid frames or sheets of plywood, and straps of rope to bind the press. Since a standard herbarium mounting sheet measures 28 cm x 43 cm, a standard plant press size is about 30 cm x 50 cm. Even if you do not plan to mount your plants on herbarium paper, this is a good sized press. All blotters, ventilators and frames should be cut to this size.

Collecting plants
When collecting a plant for study or reference, dig down to include part of the root, if possible. Identification will be easier and your collection more interesting if you collect plants bearing flowers or fruit. Some plants just cannot be positively identified unless flowers or fruit are present. Avoid thick, woody stems: a single small branch will do for trees or shrubs. If a specimen is too tall for your press, fold it to fit, or find a smaller specimen. Some plants will wilt quickly and should be placed in the press soon after collection; others can be carried home in plastic bags.

Preserving plants
Place each plant between two blotters, or in a fold of newspaper several sheets thick. Stack units like this as much as a foot (0.5 m) or more high, with cardboard sheets generously dispersed throughout the pile. The corrugations in the cardboard act as ventilators to allow airflow through the press. Ideally one ventilator should separate each two blotter units. Place a rigid frame or sheet of plywood on top and bottom, then bind the press securely with straps, or place heavy weights on top. Change the blotters frequently at first: twice at 12-hour intervals and then daily. Allow a week for thorough drying if the press is in a warm place where are circulates freely. Succulent plants will take longer. If the plant feels cool to your cheek, it is not yet dry. Plants removed when not completely dry will curl; plants left too long in the press become brittle.

For informal specimens, like small flowers or single leaves, a telephone book is nice and absorbent, and also portable. You still need weights on top to hold the plants flat, and as pages become damp the specimens should be moved to a dry part of the book.

Use spots of glue or thin strips of cloth tape to attach the dried plants to mounting paper. Heavy paper or light card is suitable. Be sure to record date and place of collection, habitat, and your name, in the lower right-hand corner.

The Museum of Natural History maintains a reference herbarium of Nova Scotian plants. Consult our botanist for more information on the collection.

To identify plants, consult these books or contact the Museum...

Summer Key to Woody Plants of Nova Scotia
Trees of Nova Scotia
Flora of Nova Scotia
Edible Wild Plants of Nova Scotia, from the Nova Scotia Government Bookstore, Halifax.
Peterson Field Guides to Trees and Wildfowers, from most retail bookstores.

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