The world famous, Royal Botanical Gardens in Sydney Australia have an herbarium collection of over 1.2 million species of plants in over 77 thousand plastic boxes. The collections of dried plants are used for studies by scientists from around the world.
These collections are under attack by the Drugstore Beetle, Stegobium paniceum. These tiny beetles, barely 1 mm X 2 mm are difficult to exclude from the valuable collections of plant material. They readily squeeze through tiny cracks and into envelopes containing the plants. The beetles have hard mandibles that can chew through aluminum foil and other packaging material. Because of the small size of the beetle and massive size of the collection, control is difficult.
Drugstore beetles are common pests of dried plant materials including spices. A home infestation of from drugstore beetle can be controlled by freezing the infested products and discarding them. This is not possible for a herbarium collection. Insecticides can be useful, but create hazards for scientists who must handle the specimens. Traps baited with the female drugstore beetle pheromone can attract and kill males. This technique is important for detecting the beetles, but it does not control the egg laying female beetles.
The inability to control the beetle and preserve the collections may force the Botanical Gardens to build a new structure to house their collection that has better features for excluding and controlling the beetles.