Specimens may also be complemented by photographs added to the sheet. Since these specimens may be preserved in much the same way as plants, their place in herbaria has been maintained. However, no herbaria attempt to fully represent the diverse kingdoms of Fungi or Monera. A herbarium specimen is simple in form and low-tech in preparation, yet it preserves a wealth of valuable information. If properly stored, a herbarium specimen will last for centuries without much deterioration.
Specimens document the variation in form and geographical range of species.
Specimens preserve short-lived structures like cactus fruits, and rarely produced organs such as bamboo flowers. The data label preserves valuable information about plant habitats. Many herbarium specimens record the existence of plants in habitats now developed and lost. They may also record the spread of weeds and new introductions like the European Helleborine orchid in Michigan. Some herbaria house the last preserved material of extinct plant species, such as the bizarre Thismia americana , once found in wet prairies near Chicago.