There are several alternative techniques for preserving leaves to use in the classroom.
- Pressed and dried leaves glued onto a sheet of paper. A collection of such leaves is known as "an herbarium." Instructions for creating an herbarium are here: Download Anderson's Herbarium Guide
- A plant press isn't required: use an old telephone book or catalog.
- Or place a single leaf between several sheets of newspaper, and put it in the microwave with a heavy dish to flatten it. Zap for 30 second intervals for about 2 minutes, until dry.
- Scan whole leaves on a flatbed scanner. This example was scanned at 300 dpi: Download Scan-001.
- Immerse the cut end of a branch in a mixture of 1:3 glycerine:water for at least 3 days. (Glycerin(e) is available at Whole Foods.) This is especially good for colored leaves.
An article about the history of herbaria, from the American Biology Teacher. Download Herbaria
Plant specimens preserved in herbaria can become important research subjects many years after they were collected. Here are 3 examples: Julius Bisky in Flushing, Xyris-a new species, Global Warming evidence found in herbarium specimens
Some links to images in virtual herbaria:
http://www.tropicos.org/Image/1350
http://sweetgum.nybg.org/vh/specimen.php?irn=568357
http://linnean-online.org/view/collection/linnean=5Fherbarium/Acer.html
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