Second, herbarium specimens are tangible evidence for new introductions as they occur; they can be the first documentation of a species being found in a new place. Take, for example, this specimen of sharpleaf cancerwort (Kickxia elatine) collected in 1979. Native to Eurasia, this (admittedly adorable) herb has spread across the United States as an occasionally noxious weed. Collector David Keil, a renowned California botanist, noticed this new species for the area and collected this specimen as early evidence of invasion. With this documentation, other botanists, conservationists, and land managers can know to be on the lookout for this potentially threatening species.
- anthropogenic - caused by or initiated by humans
- asexual reproduction - reproduction that occurs without the combination of gametes, such as by producing clonal shoots
- noxious weed - plant taxon that has been designated by a governmental or other entity to be harmful to crops, native ecosystems, or livestock
- sexual reproduction - reproduction that occurs with the combination of gametes, such as that facilitated by flowers
- Bell DS, McNeill R. 2016. Zeuxine strateumatica. Crossosoma 42(2):93-94.
- Dolan RW, Moore ME, Stephens JD. 2011. Documenting effects of urbanization on flora using herbarium records. Journal of Ecology. 99:1055-1062.
- Lambrinos JG. 2001. The expansion history of a sexual and asexual species of Cortaderia in California, USA. Journal of Ecology. 89:88-98.
- Pearson KD, Mast AM. 2019. Mobilizing the community of biodiversity specimen collectors to effectively detect and document outliers in the Anthropocene. American Journal of Botany. 106(8): 1052–1058. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6851561/pdf/AJB2-106-1052.pdf