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Persistence is the retention of plant organs, such as flowers, seeds, or leaves, after their normal function has been completed, in contrast with the shedding of deciduous organs after their purpose has been fulfilled. Absence or presence of persistent plant organs can be a helpful clue in plant identification, and may be one of many types of anatomical details noted in the species descriptions or dichotomous keys of plant identification guides. Many species of woody plants with persistent fruit provide an important food source for birds and other wildlife in winter.

The terms persistent and deciduous are not used in a consistent manner by botanists. Related terms such as long-persistent, generally deciduous, and caducous suggest that some plant parts are more persistent than others. However, these terms lack clear definitions.

Species with persistent parts

There are numerous herbaceous and woody plant species that produce persistent parts such as bud scales, sepals (calyx), fronds, fruits, seeds, strobili (cones) or styles. Note that the trait of persistence exhibited by a given species within a genus may not be exhibited by all species within the genus. For example, the Equisetum genus includes some species that have persistent strobili while other species have deciduous strobili.

Common witch-hazel (Hamamelis virginiana) may have a persistent calyx or a persistent fruit (or both at the same time). After flowering in the fall, the sepals (calyx) and pollinated ovary persist during the winter months. After the ovary is fertilized in the spring, it fuses with the calyx to form a greenish fruit, which eventually becomes woody and brown. In the fall, the ripe fruit suddenly splits, explosively dispersing black seeds up to 10 m (33 ft). The empty capsule persists after the seeds are dispersed.

Image gallery

• Larix decidua has persistent seed cones.
• Equisetum arvense has persistent strobili.
• This Cornus florida cultivar has persistent fruit into winter.
• Seed cones of Pinus banksiana persist on branches long after seeds are released.
• Berberis thunbergii has persistent fruit.
• Malus sargentii has persistent fruit.
• Serotinous seed cones of Picea mariana persist even after fire has caused the seeds to be released.
• Fruit of this Aronia arbutifolia cultivar persist through the winter and into early spring when new buds are emerging.
• Hamamelis virginiana with persistent calyx in April
• Hamamelis virginiana with persistent fruit in April

See also

• Evergreen
• Semi-deciduous
• Marcescence

References

1. Hitchcock, C. Leo; Cronquist, Arthur (2018). Flora of the Pacific Northwest (2nd ed.). Seattle: University of Washington Press. p. xxxviii, xliii. ISBN 978-0-29574-288-5.
2. Saupe, Stephen. "Plant Identification (featuring Taxonomic Keys)". College of St. Benedict/St. John's University. Retrieved 2022-05-01.
3. ^ Jauron, Richard. "It's for the Birds!". Iowa State University Extension and Outreach. Retrieved 2022-05-01.
4. Harms, Bob. "Deciduous and Persistent". Retrieved 23 November 2023.
5. Pojar & MacKinnon (1994), pp. 428–431.
6. ^ "Persistent". Master Gardeners Northern Virginia. Virginia Cooperative Extension. Retrieved 22 November 2023.
7. ^ Harms, Bob. "Persistent Bud Scales of Berberis in Central Texas". Retrieved 22 November 2023.
8. ^ Jauron, Richard. "Trees and Shrubs with Colorful Fruit in Fall and Winter". Iowa State University Extension and Outreach. Retrieved 2023-11-26.
9. "Berberis thunbergii". USDA and USFS Fire Effects Information System (FEIS). Retrieved 2023-11-28.
10. ^ Guertin, P.; Barnett, L.; Denny, E.G.; Schaffer, S.N. (2017). "Phenophase Primer for Plants (Draft Version)" (PDF). USA National Phenology Network. p. 78. Retrieved 28 November 2023.
11. "Cornus florida". Missouri Botanical Garden. Retrieved 2022-05-01.
12. Gilman, Edward; Watson, Dennis. "MALUS SARGENTII: SARGENT CRABAPPLE". University of Florida IFAS Extension. Retrieved 2022-05-01.
13. Pojar & MacKinnon (1994), p. 430.
14. Hitchcock, C. Leo; Cronquist, Arthur (2018). Flora of the Pacific Northwest (2nd ed.). Seattle: University of Washington Press. p. 68. ISBN 978-0-29574-288-5.
15. ^ Morse, Susan. "High-Hanging Fruit: Boom and Bust Seed Crops of Conifers". Northern Woodlands. Retrieved 2022-05-01.
16. Meyer, Frederick G. (1997). "Hamamelis virginiana". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 3. New York and Oxford: Oxford University Press – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
17. Meyer, Frederick G. (1997). "Hamamelis". In Flora of North America Editorial Committee (ed.). Flora of North America North of Mexico (FNA). Vol. 3. New York and Oxford: Oxford University Press – via eFloras.org, Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.

Bibliography

• Pojar, Jim; MacKinnon, Andy (1994). Plants of the Pacific Northwest Coast (2nd ed.). Lone Pine. ISBN 978-1-55105-530-5.

• Plant physiology