In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season.
A silver fir shoot showing three successive years of retained leaves.
Japanese umbrella pine is unique in that it has its own family of which it is the only species.
Differences between evergreen and deciduous speciesedit
Evergreen and deciduous species vary in a range of morphological and physiological characters. Generally, broad-leaved evergreen species have thicker leaves than deciduous species, with a larger volume of parenchyma and air spaces per unit leaf area.[2] They have larger leaf biomass per unit leaf area, and hence a lower specific leaf area. Construction costs do not differ between the groups.[citation needed] Evergreens have generally a larger fraction of total plant biomass present as leaves (LMF),[3] but they often have a lower rate of photosynthesis.
Deciduous trees shed their leaves usually as an adaptation to a cold or dry/wet season. Evergreen trees also lose leaves, but each tree loses its leaves gradually and not all at once. Most tropical rainforest plants are considered to be evergreens, replacing their leaves gradually throughout the year as the leaves age and fall, whereas species growing in seasonally arid climates may be either evergreen or deciduous. Most warm temperate climate plants are also evergreen.[citation needed] In cool temperate climates, fewer plants are evergreen. In such climates, there is a predominance of conifers because few evergreen broadleaf plants can tolerate severe cold below about −26 °C (−15 °F).[clarification needed][citation needed]
In areas where there is a reason for being deciduous, e.g. a cold season or dry season, evergreen plants are usually an adaptation of low nutrient levels. Additionally, they usually have hard leaves and have an excellent water economy due to scarce resources in the area in which they reside.[4] The excellent water economy within the evergreen species is due to high abundance when compared to deciduous species.[4] Whereas deciduous trees lose nutrients whenever they lose their leaves. In warmer areas, species such as some pines and cypresses grow on poor soils and disturbed ground.[citation needed] In Rhododendron, a genus with many broadleaf evergreens, several species grow in mature forests but are usually found on highly acidic soil where the nutrients are less available to plants.[citation needed] In taiga or boreal forests, it is too cold for the organic matter in the soil to decay rapidly, so the nutrients in the soil are less easily available to plants, thus favoring evergreens.[citation needed]
In temperate climates, evergreens can reinforce their own survival; evergreen leaf and needle litter has a higher carbon-nitrogen ratio than deciduous leaf litter, contributing to a higher soil acidity and lower soil nitrogen content. This is the case with Mediterranean evergreen seedlings, which have unique C and N storages that allow stored resources to determine fast growth within the species, limiting competition and bolstering survival.[5] These conditions favor the growth of more evergreens and make it more difficult for deciduous plants to persist. In addition, the shelter provided by existing evergreen plants can make it easier for younger evergreen plants to survive cold and/or drought.[6][7][8]
^Ewers, F. W. & Schmid, R. (1981). "Longevity of needle fascicles of Pinus longaeva (Bristlecone Pine) and other North American pines". Oecologia 51: 107–115
^Villar, Rafael; Ruiz-Robleto, Jeannete; Ubera, José Luis; Poorter, Hendrik (October 2013). "Exploring variation in leaf mass per area (LMA) from leaf to cell: An anatomical analysis of 26 woody species". American Journal of Botany. 100 (10): 1969–1980. doi:10.3732/ajb.1200562. PMID 24107583.
^Poorter, Hendrik; Jagodzinski, Andrzej M.; Ruiz-Peinado, Ricardo; Kuyah, Shem; Luo, Yunjian; Oleksyn, Jacek; Usoltsev, Vladimir A.; Buckley, Thomas N.; Reich, Peter B.; Sack, Lawren (2015). "How does biomass distribution change with size and differ among species? An analysis for 1200 plant species from five continents". New Phytologist. 208 (3): 736–749. doi:10.1111/nph.13571. PMC5034769. PMID 26197869.
^ abÁlvarez-Yépiz, Juan C.; Búrquez, Alberto; Martínez-Yrízar, Angelina; Teece, Mark; Yépez, Enrico A.; Dovciak, Martin (2017-02-01). "Resource partitioning by evergreen and deciduous species in a tropical dry forest". Oecologia. 183 (2): 607–618. Bibcode:2017Oecol.183..607A. doi:10.1007/s00442-016-3790-3. ISSN 1432-1939. PMID 27915413. S2CID 3798020. from the original on 2022-09-13. Retrieved 2021-02-16.
^Uscola, Mercedes; Villar-Salvador, Pedro; Gross, Patrick; Maillard, Pascale (2015-05-01). "Fast growth involves high dependence on stored resources in seedlings of Mediterranean evergreen trees". Annals of Botany. 115 (6): 1001–1013. doi:10.1093/aob/mcv019. ISSN 0305-7364. PMC4407060. PMID 25817313.
^Aerts, R. (1995). "The advantages of being evergreen" 2015-09-24 at the Wayback Machine. Trends in Ecology & Evolution 10 (10): 402–407.
^Matyssek, R. (1986) "Carbon, water and nitrogen relations in evergreen and deciduous conifers". Tree Physiology 2: 177–187.
^Sobrado, M. A. (1991) "Cost-Benefit Relationships in Deciduous and Evergreen Leaves of Tropical Dry Forest Species". Functional Ecology 5 (5): 608–616.
evergreen, this, article, about, type, plant, other, uses, disambiguation, botany, evergreen, plant, which, foliage, that, remains, green, functional, through, more, than, growing, season, this, contrasts, with, deciduous, plants, which, lose, their, foliage, . This article is about the type of plant For other uses see Evergreen disambiguation In botany an evergreen is a plant which has foliage that remains green and functional through more than one growing season This contrasts with deciduous plants which lose their foliage completely during the winter or dry season A silver fir shoot showing three successive years of retained leaves Contents 1 Evergreen species 1 1 Evergreen families 2 Differences between evergreen and deciduous species 3 Reasons for being evergreen or deciduous 4 See also 5 References 6 External linksEvergreen species editThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources in this section Unsourced material may be challenged and removed December 2022 Learn how and when to remove this template message There are many different kinds of evergreen plants both trees and shrubs Evergreens include Most species of conifers e g pine hemlock spruce and fir but not all e g larch Live oak holly and ancient gymnosperms such as cycads Many woody plants from frost free climates Rainforest trees All Eucalypts Clubmosses and relatives Most BamboosThe Latin binomial term sempervirens meaning always green refers to the evergreen nature of the plant for instance Cupressus sempervirens a cypress Lonicera sempervirens a honeysuckle Sequoia sempervirens a sequoia Leaf longevity in evergreen plants varies from a few months to several decades over 30 years in the Great Basin bristlecone pine 1 Evergreen families edit Family name ExampleAraucariaceae KauriCupressaceae SequoiaPinaceae PinePodocarpaceae Real yellowwoodTaxaceae YewCyatheaceae Australian tree fernAquifoliaceae HollyFagaceae Live oakOleaceae Shamel ashMyrtaceae EucalyptusArecaceae CoconutLauraceae BayMagnoliaceae Southern magnoliaCycadaceae Queen sagoJapanese umbrella pine is unique in that it has its own family of which it is the only species Differences between evergreen and deciduous species editEvergreen and deciduous species vary in a range of morphological and physiological characters Generally broad leaved evergreen species have thicker leaves than deciduous species with a larger volume of parenchyma and air spaces per unit leaf area 2 They have larger leaf biomass per unit leaf area and hence a lower specific leaf area Construction costs do not differ between the groups citation needed Evergreens have generally a larger fraction of total plant biomass present as leaves LMF 3 but they often have a lower rate of photosynthesis Reasons for being evergreen or deciduous editThis section needs additional citations for verification Please help improve this article by adding citations to reliable sources in this section Unsourced material may be challenged and removed August 2023 Learn how and when to remove this template message nbsp A southern live oak in South Carolina during winterDeciduous trees shed their leaves usually as an adaptation to a cold or dry wet season Evergreen trees also lose leaves but each tree loses its leaves gradually and not all at once Most tropical rainforest plants are considered to be evergreens replacing their leaves gradually throughout the year as the leaves age and fall whereas species growing in seasonally arid climates may be either evergreen or deciduous Most warm temperate climate plants are also evergreen citation needed In cool temperate climates fewer plants are evergreen In such climates there is a predominance of conifers because few evergreen broadleaf plants can tolerate severe cold below about 26 C 15 F clarification needed citation needed In areas where there is a reason for being deciduous e g a cold season or dry season evergreen plants are usually an adaptation of low nutrient levels Additionally they usually have hard leaves and have an excellent water economy due to scarce resources in the area in which they reside 4 The excellent water economy within the evergreen species is due to high abundance when compared to deciduous species 4 Whereas deciduous trees lose nutrients whenever they lose their leaves In warmer areas species such as some pines and cypresses grow on poor soils and disturbed ground citation needed In Rhododendron a genus with many broadleaf evergreens several species grow in mature forests but are usually found on highly acidic soil where the nutrients are less available to plants citation needed In taiga or boreal forests it is too cold for the organic matter in the soil to decay rapidly so the nutrients in the soil are less easily available to plants thus favoring evergreens citation needed In temperate climates evergreens can reinforce their own survival evergreen leaf and needle litter has a higher carbon nitrogen ratio than deciduous leaf litter contributing to a higher soil acidity and lower soil nitrogen content This is the case with Mediterranean evergreen seedlings which have unique C and N storages that allow stored resources to determine fast growth within the species limiting competition and bolstering survival 5 These conditions favor the growth of more evergreens and make it more difficult for deciduous plants to persist In addition the shelter provided by existing evergreen plants can make it easier for younger evergreen plants to survive cold and or drought 6 7 8 See also edit nbsp Plants portal nbsp Trees portal nbsp Botany portalSemi deciduous semi evergreen References edit Ewers F W amp Schmid R 1981 Longevity of needle fascicles of Pinus longaeva Bristlecone Pine and other North American pines Oecologia 51 107 115 Villar Rafael Ruiz Robleto Jeannete Ubera Jose Luis Poorter Hendrik October 2013 Exploring variation in leaf mass per area LMA from leaf to cell An anatomical analysis of 26 woody species American Journal of Botany 100 10 1969 1980 doi 10 3732 ajb 1200562 PMID 24107583 Poorter Hendrik Jagodzinski Andrzej M Ruiz Peinado Ricardo Kuyah Shem Luo Yunjian Oleksyn Jacek Usoltsev Vladimir A Buckley Thomas N Reich Peter B Sack Lawren 2015 How does biomass distribution change with size and differ among species An analysis for 1200 plant species from five continents New Phytologist 208 3 736 749 doi 10 1111 nph 13571 PMC 5034769 PMID 26197869 a b Alvarez Yepiz Juan C Burquez Alberto Martinez Yrizar Angelina Teece Mark Yepez Enrico A Dovciak Martin 2017 02 01 Resource partitioning by evergreen and deciduous species in a tropical dry forest Oecologia 183 2 607 618 Bibcode 2017Oecol 183 607A doi 10 1007 s00442 016 3790 3 ISSN 1432 1939 PMID 27915413 S2CID 3798020 Archived from the original on 2022 09 13 Retrieved 2021 02 16 Uscola Mercedes Villar Salvador Pedro Gross Patrick Maillard Pascale 2015 05 01 Fast growth involves high dependence on stored resources in seedlings of Mediterranean evergreen trees Annals of Botany 115 6 1001 1013 doi 10 1093 aob mcv019 ISSN 0305 7364 PMC 4407060 PMID 25817313 Aerts R 1995 The advantages of being evergreen Archived 2015 09 24 at the Wayback Machine Trends in Ecology amp Evolution 10 10 402 407 Matyssek R 1986 Carbon water and nitrogen relations in evergreen and deciduous conifers Tree Physiology 2 177 187 Sobrado M A 1991 Cost Benefit Relationships in Deciduous and Evergreen Leaves of Tropical Dry Forest Species Functional Ecology 5 5 608 616 External links editHelen Ingersoll 1920 Evergreens Encyclopedia Americana Retrieved from https en wikipedia org w index php title Evergreen amp oldid 1198215402, wikipedia, wiki, book, books, library,
