HOW TO MAKE A SCIENTIFIC PLANT COLLECTION

MAKING A PLANT PRESS

When scientists preserve a specimen of a plant (or part of a plant) they usually flatten it, dry it and mount it on special paper. Preserved in this way the plant specimen can be stored for many years without falling apart.

To get a good preserved specimen, the plant material that is collected in the field must be of good quality. A half-dead, wilted or dry plant does not press well and will not make a good preserved specimen. Select plant material that is growing well, is healthy and is representative of that type of plant growing in the area. When collecting the specimen, cut it to a size that will fit conveniently in the plant press. If the specimen is small enough, it can be pulled from the ground so that the whole plant, roots and all can go into the press. Sometimes a specimen will need to be folded over or trimmed a little to make it fit in the press.

Plants that have been collected need to be pressed as soon as possible. Plants can be kept in a paper or plastic bag for an hour of so, but once they start to wilt they make poor specimens. Press cut specimens as soon as possible.

The preservation process begins by flattening the plant specimen in a plant press. A plant press is made of newspapers, cardboard, blotter paper and wood and is held together with nylon straps. See the drawing below: