Re: How can my students skeletonize leaves to study venation?

The best way to see leaf venation is to simply clear the leaf material until it is transparent. This is easily done:

Place leaves, a couple at a time, in a large beaker with ethanol (at least 70% ethanol) and bring to a boil. Allow the leaves to boil until they become pale or clear. The chlorophyll dissolves in the ethanol, so the ethanol in the beaker will turn green. Different types of leaves will take different lengths of time to clear. A half hour might do the trick. Rememember not to let the leaves boil dry - more ethanol can be added to replace the volume boiled off. After the leaves are pale/clear, place them in a warm (56 C) solution of 5-10% NaOH. They may then be removed, rinsed with water and studied!

Good luck!
Dawn Gordon

Admin note: As always, be certain to follow appropriate lab safety procedures when handling solutions of sodium hydroxide (NaOH) or boiling flammable liquids such as 70% ethanol.