DENDROLOGY

Detailed explanation-1: -The type of preservative used should be clearly labelled in the jar. Such material is often referred to as a spirit collection or wet collection. Most material can be satisfactorily preserved in 70% ethyl alcohol (or 70% methylated spirit or denatured alcohol) with 30% water.

Detailed explanation-2: -In a herbarium, plants are stored in folders within airtight cabinets. Any dried plant material is frozen before entering the herbarium, and the space is periodically treated with a pyrethrin spray (an organic insecticide made from chrysanthemums).

Detailed explanation-3: -Specimen samples are pressed in a plant press and dried on a plant dryer. Each specimen sample should consist of a stem with attached leaves and, if at all possible, flowers and/or fruits. The roots of herbaceous plants should also be included.