Dendrochronology: Difference between revisions

Dendrochronology is useful for determining the precise age of samples, especially those that are too recent for [[radiocarbon dating]], which always produces a range rather than an exact date. However, for a precise date of the death of the tree a full sample to the edge is needed, which most trimmed timber will not provide. It also gives data on the timing of events and rates of change in the environment (most prominently climate) and also in wood found in [[archaeology]] or works of art and architecture, such as old [[panel painting]]s. It is also used as a check- in radiocarbon dating to [[Calibration of radiocarbon dates|calibrate radiocarbon ages]].<ref name="Grissino">{{citation|title=The Science of Tree Rings: Principles of Dendrochronology|first=Henri D.|last=Grissino-Mayer|publisher=Department of Geography, The University of Tennessee|date=n.d.|url=http://web.utk.edu/~grissino/principles.htm|access-date=October 23, 2016|url-status=live|archive-url=https://web.archive.org/web/20161104042215/http://web.utk.edu/~grissino/principles.htm|archive-date=November 4, 2016}}</ref>

New growth in [[tree]]s occurs in a layer of cells near the bark. A tree's growth rate changes in a predictable pattern throughout the year in response to seasonal climate changes, resulting in visible growth rings. Each ring marks a complete cycle of [[season]]s, or one year, in the tree's life.<ref name="Grissino" /> As of 20202023, securely dated tree-ring data for theGermany [[Northernand Hemisphere]]Ireland are available going back 13,910 years.<ref>{{cite journal |last1=Van der Plecht |first1= J |last2=Bronck Ramsey |first2=C |last3=Heaton |first3=T. J. |last4=Scott |first4=E. M. |last5=Talamo |first5=S |title=Recent Developments in Calibration for Archaeological and Environmental Samples |journal=Radiocarbon |date=August 2020 |volume=62 |issue=4 |pages=1095–1117 |doi=10.1017/RDC.2020.22 |bibcode= 2020Radcb..62.1095V |doi-access=free |hdl=11585/770537 |hdl-access=free }}</ref><ref>{{cite book|last=Holliday |first=Trenton |title=Cro-Magnon: The Story of the Last Ice Age People of Europe|page=44 |publisher= Columbia University Press|location =New York |year=2021|isbn=978-0-231-20497-2}}</ref> A new method is based on measuring variations in oxygen isotopes in each ring, and this 'isotope dendrochronology' can yield results on samples which are not suitable for traditional dendrochronology due to too few or too similar rings.<ref>{{cite journal |last1=Loader |first1=Neil J. |last2=Mccarroll |first2=Danny |last3=Miles |first3=Daniel |last4=Young |first4=Giles H. F. |last5=Davies |first5=Darren |last6=Ramsey |first6=Christopher Bronk |title=Tree ring dating using oxygen isotopes: a master chronology for central England |journal=Journal of Quaternary Science |date=August 2019 |volume=34 |issue=6 |pages=475–490 |doi=10.1002/jqs.3115 |bibcode=2019JQS....34..475L |doi-access=free |url=https://cronfa.swan.ac.uk/Record/cronfa50379/Download/0050379-28082019112451.pdf }}</ref> Some regions have "floating sequences", with gaps which mean that earlier periods can only be approximately dated. As of 2024, only three areas have continuous sequences going back to prehistoric times, the foothills of the [[Northern Limestone Alps|Northern Alps]], the southwestern United States and the British Isles. [[Miyake event]]s, which are major spikes in [[cosmic rays]] at known dates, are visible in trees rings and can fix the dating of a floating sequence.<ref name=Bern>{{cite web|url=https://phys.org/news/2024-05-succeed-accurately-dating-year-prehistoric.html|author=University of Bern|date=21 May 2024|title=Researchers succeed for first time in accurately dating a 7,000-year-old prehistoric settlement using cosmic rays}}</ref>

* {{cite journal |last1=Studhalter |first1=R. A. |title=Early History of Crossdating |journal=Tree-Ring Bulletin |date=April 1956 |volume=21 |pages=31–35 |hdl=10150/259045 |hdl-access=free }} (Condensed from: {{cite journal |last1=Studhalter |first1=R. A. |title=Tree Growth I. Some Historical Chapters |journal=Botanical Review |date=1955 |volume=21 |issue=1/3 |pages=1–72 |doi=10.1007/BF02872376 |jstor=4353530 |s2cid=37646970 }}

* {{cite journal |last1=Studhalter |first1=R. A. |last2=Glock |first2=Waldo S. |last3=Agerter |first3=Sharlene R. |title=Tree Growth: Some Historical Chapters in the Study of Diameter Growth |journal=Botanical Review |date=1963 |volume=29 |issue=3 |pages=245–365 |doi=10.1007/BF02860823 |jstor=4353671 |s2cid=44817056 }}

* James H. Speer, ''Fundamentals of Tree-ring Research'' (Tucson, Arizona: University of Arizona Press, 2010), Chapter 3: History of Dendrochronology, pp. 28–42.</ref> In his ''[[Trattato della Pittura]]'' (Treatise on Painting), [[Leonardo da Vinci]] (1452–1519) was the first person to mention that trees form rings annually and that their thickness is determined by the conditions under which they grew.<ref>See:

* Leonardo da Vinci, ''Trattato della Pittura'' ... (Rome, (Italy): 1817), [https://archive.org/stream/trattatopittura01leon#page/396/mode/1up/ p. 396.] From p. 396: ''"Li circuli delli rami degli alberi segati mostrano il numero delli suoi anni, e quali furono più umidi o più secchi la maggiore o minore loro grossezza."'' (The rings around the branches of trees that have been sawed show the number of its years and which [years] were the wetter or drier [according to] the more or less their thickness.)

* [[Sarton, George]] (1954) "Queries and Answers: Query 145. — When was tree-ring analysis discovered?", ''[[Isis (journal)|Isis]]'', '''45''' (4): 383–384. Sarton also cites a diary of the French writer [[Michel de Montaigne]], who in 1581 was touring Italy, where he encountered a carpenter who explained that trees form a new ring each year.</ref> In 1737, French investigators [[Henri-Louis Duhamel du Monceau]] and [[Georges-Louis Leclerc de Buffon]] examined the effect of growing conditions on the shape of tree rings.<ref>du Hamel & de Buffon (27 February 1737) [http://gallica.bnf.fr/ark:/12148/bpt6k3534v/f263.image.r=l%27aubier.langEN ''"De la cause de l'excentricité des couches ligneuses qu'on apperçoit quand on coupe horisontalement le tronc d'un arbre ; de l'inégalité d'épaisseur, & de different nombre de ces couches, tant dans le bois formé que dans l'aubier"''] {{Webarchive|url=https://web.archive.org/web/20150509195022/http://gallica.bnf.fr/ark%3A/12148/bpt6k3534v/f263.image.r%3Dl%27aubier.langEN |date=2015-05-09 }} (On the cause of the eccentricity of the woody layers that one sees when one horizontally cuts the trunk of a tree ; on the unequal thickness, and on the different number of layers in the mature wood as well as in the sapwood), ''Mémoires de l'Académie royale des science'', in: ''Histoire de l'Académie royale des sciences'' ..., pp. 121–134.</ref> They found that in [[Great Frost of 1709|1709, a severe winter]] produced a distinctly dark tree ring, which served as a reference for subsequent European naturalists.<ref>du Hamel & de Buffon (4 May 1737) [http://gallica.bnf.fr/ark:/12148/bpt6k3534v/f425.image.r=l%27aubier.langEN "Observations des différents effets que produisent sur les végétaux les grandes gelées d'hiver et les petites gelées du printemps"] {{Webarchive|url=https://web.archive.org/web/20150509235420/http://gallica.bnf.fr/ark%3A/12148/bpt6k3534v/f425.image.r%3Dl%27aubier.langEN |date=2015-05-09 }}

* (Anon.) (1835) [https://books.google.com/books?id=dfNPAAAAMAAJ&pg=PA116 "Evening meeting at the Rotunda"] {{webarchive|url=https://web.archive.org/web/20150514194852/https://books.google.com/books?id=dfNPAAAAMAAJ&pg=PA116 |date=2015-05-14 }}, ''Proceedings of the Fifth Meeting of the British Association for the Advancement of Science held in Dublin during the week from the 10th to the 15th of August, 1835, inclusive'', pp. 116–117.

* Charles Babbage (1838) [https://booksarchive.google.comorg/details/ninthbridgewatai00babb/books?id=y_ERAAAAYAAJ&pg=PA256page/226 "On the age of strata, as inferred from rings of trees embedded in them"] {{webarchive|url=https://web.archive.org/web/20150515051525/https://books.google.com/books?id=y_ERAAAAYAAJ&pg=PA256 |date=2015-05-15 }}, ''The Ninth Bridgewater Treatise: A Fragment'', 2nd ed. ([[London]], [[England]]: John Murray, 18381837), pp. 256–264226-234.</ref>

* [[Jacob Kuechler]] ( August 6, 1859) "Das Klima von Texas" (The climate of Texas), ''Texas Staats-Zeitung'' [Texas state newspaper] (San Antonio, Texas), p. 2.

* "The droughts of western Texas", ''The Texas Almanac for 1861'', pp. 136–137 ; see [http://texashistory.unt.edu/ark:/67531/metapth123767/m1/137/ especially p. 137.] {{webarchive|url=https://web.archive.org/web/20151102005729/http://texashistory.unt.edu/ark:/67531/metapth123767/m1/137/ |date=2015-11-02 }}</ref> In 1866, the German botanist, entomologist, and forester [[Julius Theodor Christian Ratzeburg]] (1801–1871) observed the effects on tree rings of defoliation caused by insect infestations.<ref>J. T. C. Ratzeburg, ''Die Waldverderbniss oder dauernder Schade, welcher durch Insektenfrass, Schälen, Schlagen und Verbeissen an lebenenden Waldbäumen entsteht.'' [The deterioration of forests or lasting damage that arises from feeding by insects, debarking, felling, and gnawing on living forest trees.], vol. 1, (Berlin, (Germany): Nicolaische Verlag, 1866), [https://books.google.com/books?id=miZAAAAAcAAJ&pg=PA10 p. 10.] {{webarchive|url=https://web.archive.org/web/20151001154134/https://books.google.com/books?id=miZAAAAAcAAJ&pg=PA10 |date=2015-10-01 }} From p. 10: ''"Die beiden, auf Taf. 42, Fig. 6 (mit dem Durchschnitt Fig. 7) und Fig. 1 (mit dem Durchschnitt Fig. 2) dargestellten Zweige hatten in dem Frassjahre 1862 einen doppelt so starken Jahrring als in dem vorhergehenden angelegt, und auch der (hier nicht abgebildete) Ring des jährigen Triebes war bei den gefressenen stärker as der eines nicht gefressenen."'' (Both branches that are presented in plate 42, fig. 6 (with the cross-section in fig. 7) and fig. 1 (with the cross-section in fig. 2) had produced, in the defoliation year of 1862, a growth ring that was twice as strong as in the preceding one, and so was the ring of the year-old shoot (not illustrated here) stronger in the case of the defoliated tree than one that was not defoliated.)</ref> By 1882, this observation was already appearing in [[forestry]] textbooks.<ref>[[Franklin B. Hough]], ''The Elements of Forestry'' (Cincinnati, Ohio: Robert Clarke and Co., 1882), [https://books.google.com/books?id=XB0DAAAAYAAJ&pg=PA69 pp. 69–70.] {{webarchive|url=https://web.archive.org/web/20151001154638/https://books.google.com/books?id=XB0DAAAAYAAJ&pg=PA69 |date=2015-10-01 }}</ref> In the 1870s, the Dutch astronomer [[Jacobus Kapteyn]] (1851–1922) was using crossdating to reconstruct the climates of the Netherlands and Germany.<ref>Kapteyn, J. C. (1914) [http://babel.hathitrust.org/cgi/pt?id=uiug.30112111806425;view=1up;seq=88 "Tree-growth and meteorological factors"], ''Recueil des Travaux Botaniques Néerlandais'', '''11''' : 70–93.</ref> In 1881, the Swiss-Austrian forester Arthur [[House of Seckendorff|von Seckendorff]]-Gudent (1845–1886) was using crossdating.<ref>See:

* Seckendorff, Arthur von (1881) "Beiträge zur Kenntnis der Schwarzföhre ''Pinus austriaca'' Höss" [Contributions to our knowledge of the black pine ''Pinus austriaca'' Höss], ''Mitteilung aus dem forstlichen Versuchswesen Oesterreichs'' [Report from the Austrian Department of Forestry Research] (Vienna, Austria: Carl Gerold Verlag, 1881), 66 pages.

* Speer (2010), p. 36.</ref> From 1869 to 1901, [[Robert Hartig]] (1839–1901), a German professor of forest pathology, wrote a series of papers on the anatomy and ecology of tree rings.<ref>Speer (2010), p. 36–37.</ref> In 1892, the Russian physicist [[w:Шведов,{{interlanguage Фёдор Никифоровичlink|Fedor Nikiforovich Shvedov]]|ro|Fiodor ({{langȘvedov|ru|Шведов, Фёдор Никифорович |uk|Шведов Федір Никифорович}}; (1841–1905) wrote that he had used patterns found in tree rings to predict droughts in 1882 and 1891.<ref>See:

* Шведов, Ф. (Shvedov, F.) (1892) "Дерево, как летопись засух" (The tree as a record of drought), ''Метеорологический Вестник'' (Meteorological Herald), (5) : 163–178.

* Speer (2010), p. 37.</ref>

Horizontal [[cross section (geometry)|cross sections]] cut through the [[trunk (botany)|trunk]] of a [[tree]] can reveal growth rings, also referred to as '''tree rings''' or '''annual rings'''. Growth rings result from new growth in the [[vascular cambium]], a layer of cells near the [[bark (botany)|bark]] that botanists classify as a [[lateral meristem]]; this growth in diameter is known as [[secondary growth]]. Visible rings result from the change in growth speed through the [[season]]s of the year; thus, critical for the title method, one ring generally marks the passage of one year in the life of the tree. Removal of the bark of the tree in a particular area may cause deformation of the rings as the plant overgrows the scar.

The rings are more visible in trees which have grown in [[temperate zone]]s, where the seasons differ more markedly. The inner portion of a growth ring forms early in the growing season, when growth is comparatively rapid (hence the wood is less dense) and is known as "early wood" (or "spring wood", or "late-spring wood"<ref>"Early wood" is used in preference to "spring wood", as the latter term may not correspond to that time of year in climates where early wood is formed in the early summer (e.g. [[Canada]]) or in autumn, as in some [[Mediterranean region|Mediterranean]] species.</ref>); the outer portion is the "late wood" (sometimes termed "summer wood", often being produced in the summer, though sometimes in the autumn) and is denser.<ref>{{Cite book |last= Capon |first= Brian |title= Botany for Gardeners |year= 2005 |pages= 66–67 |edition= 2nd |isbn= 978-0-88192-655-2 |publisher= Timber Publishing |location= Portland, OR}}</ref>{{better source needed|date= November 2014}}

Direct reading of tree ring chronologies is a complex science, for several reasons. First, contrary to the single-ring-per-year paradigm, alternating poor and favorable conditions, such as mid-summer droughts, can result in several rings forming in a given year. In addition, particular tree species may present "missing rings", and this influences the selection of trees for study of long time-spans. For instance, missing rings are rare in [[oak]] and [[elm]] trees.<ref>The only recorded instance of a missing ring in oak trees occurred in the year 1816, also known as the "[[Year Without a Summer]]".{{cite web | url = http://www.ltrr.arizona.edu/lorim/good.html | title= Useful Tree Species for Tree-Ring Dating | author= Lori Martinez | year= 1996 | access-date= 2008-11-08 | url-status= live | archive-url= https://web.archive.org/web/20081108094321/http://www.ltrr.arizona.edu/lorim/good.html | archive-date= 2008-11-08 }}</ref>

Critical to the science, trees from the same region tend to develop the same patterns of ring widths for a given period of chronological study. Researchers can compare and match these patterns ring-for-ring with patterns from trees which have grown at the same time in the same geographical zone (and therefore under similar climatic conditions). When one can match these tree-ring patterns across successive trees in the same locale, in overlapping fashion, chronologies can be built up—both for entire geographical regions and for sub-regions. Moreover, wood from ancient structures with known chronologies can be matched to the tree-ring data (a technique called ''cross-dating''), and the age of the wood can thereby be determined precisely. Dendrochronologists originally carried out cross-dating by visual inspection; more recently, they have harnessed computers to do the task, applying statistical techniques to assess the matching. To eliminate individual variations in tree-ring growth, dendrochronologists take the smoothed average of the tree-ring widths of multiple tree-samples to build up a '''ring history''', a process termed replication. A tree-ring history whose beginning- and end-dates are not known is called a ''floating chronology''. It can be anchored by cross-matching a section against another chronology (tree-ring history) whose dates are known.

A fully anchored and cross-matched chronology for oak and pine in central Europe extends back 12,460 years,<ref>{{cite journal |last1=Friedrich |first1=Michael |last2=Remmele |first2=Sabine |last3=Kromer |first3=Bernd |last4=Hofmann |first4=Jutta |last5=Spurk |first5=Marco |last6=Felix Kaiser |first6=Klaus |last7=Orcel |first7=Christian |last8=Küppers |first8=Manfred |title=The 12,460-Year Hohenheim Oak and Pine Tree-Ring Chronology from Central Europe—A Unique Annual Record for Radiocarbon Calibration and Paleoenvironment Reconstructions |journal=Radiocarbon |date=2004 |volume=46 |issue=3 |pages=1111–1122 |doi=10.1017/S003382220003304X |bibcode=2004Radcb..46.1111F |s2cid=53343999 |url=http://physics2.fau.edu/~wolf/BasicScience/Friedrich_Dendro_RC04.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://physics2.fau.edu/~wolf/BasicScience/Friedrich_Dendro_RC04.pdf |archive-date=2022-10-09 |url-status=live }}</ref> and an oak chronology goes back 7,429 years in Ireland and 6,939 years in [[England]].<ref>{{cite book |chapter-url= https://books.google.com/books?id=1rYCjUzMM3UC&q=northern+ireland+dendrochronological&pg=PT145 |chapter= 5.2.3 Dendrochronological Series |first= Mike |last= Walker |title= Quaternary Dating Methods |publisher= John Wiley and Sons |year= 2013 |isbn= 9781118700099 |url-status= live |archive-url= https://web.archive.org/web/20161128050944/https://books.google.co.uk/books?id=1rYCjUzMM3UC&pg=PT145&lpg=PT145&dq=northern+ireland+dendrochronological&source=bl&ots=-83vqIKmdt&sig=gvKAhREENtGBCdVV2TK7131y92I&hl=en&sa=X&ved=0ahUKEwjR65yEzcnQAhXKCsAKHUP_CG84ChDoAQgqMAM#v=onepage&q=northern%20ireland%20dendrochronological&f=false |archive-date= 2016-11-28}}</ref> Comparison of radiocarbon and dendrochronological ages supports the consistency of these two independent dendrochronological sequences.<ref>{{cite journal |last1=Stuiver |first1=Minze |last2=Kromer |first2=Bernd |last3=Becker |first3=Bernd |last4=Ferguson |first4=C W |title=Radiocarbon Age Calibration back to 13,300 Years BP and the {{chem|14|C}} Age Matching of the German Oak and US Bristlecone Pine Chronologies |journal=Radiocarbon |date=1986 |volume=28 |issue=2B |pages=969–979 |doi=10.1017/S0033822200060252 |bibcode=1986Radcb..28..969S |doi-access=free |hdl=10150/652767 |hdl-access=free }}</ref> Another fully anchored chronology that extends back 8,500 years exists for the bristlecone pine in the [[Southwestern United States|Southwest US]] ([[White Mountains (California)|White Mountains]] of California).<ref>{{cite journal |last1=Ferguson |first1=C. W. |last2=Graybill |first2=D. A. |title=Dendrochronology of Bristlecone Pine: A Progress Report |journal=Radiocarbon |date=1983 |volume=25 |issue=2 |pages=287–288 |doi=10.1017/S0033822200005592 |bibcode=1983Radcb..25..287F |hdl=10150/652656 |hdl-access=free |doi-access=free }}</ref>

<big><math display="block">\Delta L(t) = -\frac{ c_1 e^{-a_1 t}+ c_2 e^{-a_2 t} }{3 k_v \rho^{\frac{1}{3}} \left(c_4+ c_1 e^{-a_1 t}+ c_2 e^{-a_2 t}\right)^{\frac{2}{3}}}</math></big>

The formula is useful for correct approximation of samples data before [[data normalization]] procedure. The typical forms of the function Δ''L''(''t'') of annual growth of wood ring are shown in the figures.

IntCal20 is the 2020 "Radiocarbon Age Calibration Curve", which provides a calibrated [[carbon 14]] dated sequence going back 55,000 years. The most recent part, going back 13,900 years, is based on tree rings.<ref>{{cite journal|title=The IntCal20 Northern Hemisphere Radiocarbon Age Calibration Curve (0–55 cal kBP)|first=Paula|last=Reimer|display-authors=etal|date= 12 August 2020|journal=Radiocarbon|volume=62|issue=4|pages=725–757|doi=10.1017/RDC.2020.41|bibcode=2020Radcb..62..725R |s2cid=216215614|doi-access=free|hdl=11585/770531|hdl-access=free}}</ref>

European chronologies derived from wooden structures initially found it difficult to bridge the gap in the fourteenth century when there was a building hiatus, which coincided with the [[Black Death]],.<ref>{{cite book

}}</ref>. However, there do exist unbroken chronologies dating back to prehistoric times, for example the Danish chronology dating back to 352 BC.<ref>{{cite web|url=http://www.skalk.dk/Sider/0003wm.html |website=skalk.dk |title=WM Trædatering |language=da |trans-title=WM Tree dating |access-date=15 May 2015 |url-status=dead |archive-url=https://web.archive.org/web/20141221121805/http://www.skalk.dk/Sider/0003wm.html |archive-date=21 December 2014 }}</ref>

Given a sample of wood, the variation of the tree-ring growths not only provides a match by year, but can also match location because climate varies from place to place. This makes it possible to determine the source of ships as well as smaller artifacts made from wood, but which were transported long distances, such as panels for paintings and ship timbers.{{citation needed|date=February 2024}}

===RadiocarbonMiyake time markersevents===

[[Miyake event]]s, such as the ones in [[774–775 carbon-14 spike|774-775774–775]] and [[993–994 carbon-14 spike|993-994993–994]], can provide fixed reference points in an unknown time sequence as they are due to cosmic radiation.<ref name =Maczkowski>Andrej Maczkowski et al, "Absolute dating of the European Neolithic using the 5259 BC rapid 14C excursion", Nature Communications, 2024 {{doi|10.1038/s41467-024-48402-1}}</ref> As they appear as spikes in [[carbon 14]] in tree rings for that year all round the world, they can be used to date historical events to the year.<ref>{{Cite web |last=Price |first=Michael |date=13 April 2023 |title=Marking time: Radiocarbon timestamps left in ancient tree rings by cosmic ray bombardments can date historical events with unprecedented precision |url=https://www.science.org/content/article/marking-time-cosmic-ray-storms-can-pin-precise-dates-history-ancient-egypt-vikings|website=[[Science (journal)|Science]] |quote=A previous version "Marking time: Cosmic ray storms can pin precise dates on history from ancient Egypt to the Vikings" appeared in Science, Vol 380, Issue 6641.}}</ref> For example, wooden houses in the [[Viking]] site at [[L'Anse aux Meadows]] in Newfoundland were dated by finding the layer with the 993 spike, which showed that the wood is from a tree felled in 1021.<ref>{{cite journal|url=https://www.nature.com/articles/s41586-021-03972-8.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.nature.com/articles/s41586-021-03972-8.pdf |archive-date=2022-10-09 |url-status=live|journal=Nature|title=Evidence for European presence in the Americas in AD 1021|first=Margot|last= Kuitems|display-authors=etal|date=20 October 2021|volume=601|issue=7893|pages=388–391|doi=10.1038/s41586-021-03972-8|pmid=34671168|pmc=8770119|s2cid=239051036}}</ref> Researchers at the University of Bern have provided exact dating of a floating sequence in a [[Neolithic]] settlement in northern Greece by tying it to a spike in cosmogenic radiocarbon in 5259 BC.<ref name=Bern/><ref name =Maczkowski/>

Frost ring is a term used to designate a layer of deformed, collapsed [[tracheid]]s and traumatic [[parenchyma]] cells in tree ring analysis. They are formed when air temperature falls below freezing during a period of [[cambial]] activity. They can be used in dendrochronology to indicate years that are colder than usual.<ref>{{cite journal |display-authors=etal|last1=David Montwé |title=Cold adaptation recorded in tree rings highlights risks associated with climate change and assisted migration |journal=Nature Communications |date=Apr 23, 2018 |volume=9 |issue=1 |page=1574 |doi=10.1038/s41467-018-04039-5 |url=https://www.nature.com/articles/s41467-018-04039-5|doi-access=free |pmid=29686289 |pmc=5913219 |bibcode=2018NatCo...9.1574M }}</ref>

[[Dendroclimatology]] is the science of determining past [[climate]]s from [[tree]]s primarily from the properties of the annual tree rings.<ref>{{cite journal |last1=Sheppard |first1=Paul R. |title=Dendroclimatology: extracting climate from trees: Dendroclimatology |journal=Wiley Interdisciplinary Reviews: Climate Change |date=May 2010 |volume=1 |issue=3 |pages=343–352 |doi=10.1002/wcc.42 |s2cid=129124697 }}</ref> Other properties of the annual rings, such as maximum [[latewood]] density (MXD) have been shown to be better proxies than simple ring width. Using tree rings, scientists have estimated many local climates for hundreds to thousands of years previous.{{citation needed|date=February 2024}}

[[File:Mary Queen of Scots portrait.jpg|thumb|left|A portrait of Mary, Queen of Scots, determined to date from the sixteenth century by dendrochronology]]

Since panels of seasoned wood were used, an uncertain number of years has to be allowed for seasoning when estimating dates.<ref>Peter Ian Kuniholm, [http://dendro.cornell.edu/articles/kuniholm2000.pdf ''Dendrochronology (Tree-Ring Dating) of Panel Paintings''] {{webarchive|url=https://web.archive.org/web/20131017230735/http://dendro.cornell.edu/articles/kuniholm2000.pdf |date=2013-10-17 }} Cornell University</ref> Panels were trimmed of the outer rings, and often each panel only uses a small part of the [[radius]] of the trunk. Consequently, dating studies usually result in a "''[[terminus post quem]]"'' (earliest possible) date, and a tentative date for the arrival of a seasoned raw panel using assumptions as to these factors.<ref>{{cite book |first1=W. Stanley |last1=Taft |first2=James W. |last2=Mayer |first3=Richard |last3=Newman |first4=Peter Ian |last4=Kuniholm |first5=Dusan |last5=Stulik |title=The Science of Paintings |url=https://books.google.com/books?id=L8J4Mhb1kjUC&pg=PR6 |year=2000 |publisher=Springer |isbn=978-0-387-98722-4 |chapter=Dendrochronology (Tree-Ring Dating) of Panel Paintings |chapter-url=http://www.arts.cornell.edu/dendro/painttex.html |pages=206–215 |url-status=live |archive-url=https://web.archive.org/web/20170422142755/https://books.google.com/books?id=L8J4Mhb1kjUC&pg=PR6 |archive-date=2017-04-22 }}</ref> As a result of establishing numerous sequences, it was possible to date 85–90% of the 250 paintings from the fourteenth to seventeenth century analysed between 1971 and 1982;<ref>{{cite journal |last1=Fletcher |first1=John |title=Panel Examination and Dendrochronology |journal=The J. Paul Getty Museum Journal |date=1982 |volume=10 |pages=39–44 |jstor=4166459 }}</ref> by now a much greater number have been analysed.

A portrait of [[Mary, Queen of Scots]] in the [[National Portrait Gallery, London]] was believed to be an eighteenth-century copy. However, dendrochronology revealed that the wood dated from the second half of the sixteenth century. It is now regarded as an original sixteenth-century painting by an unknown artist.<ref>[{{cite web |url-status=live |url=http://www.npg.org.uk/collections/search/portraitConservation/mw04272/Mary-Queen-of-Scots#dendro |website=National Portrait gallery]Gallery {{webarchive|archive-url=https://web.archive.org/web/20131017160354/http://www.npg.org.uk/collections/search/portraitConservation/mw04272/Mary-Queen-of-Scots |archive-date=2013-10-17 |at=Dendrochronology |title=Mary, Queen of Scots }}</ref>

On the other hand, dendrochronology was applied to four paintings depicting the same subject, that of [[Cleansing of the Temple|Christ expelling the money-lenders from the Temple]]. The results showed that the age of the wood was too late for any of them to have been painted by [[Hieronymus Bosch]].<ref>[{{cite web |url-status=dead |url=http://www.atomium-culture.ilsole24ore.com/?p=78 |work=Atomium Culture |publisher=Il Sole 24 Ore |title=Tree Rings, the barcodesBarcodes of Nature, illuminateIlluminate artArt history]History {{webarchive|first1=Alar |last1=Läänelaid |date=June 19, 2013 |archive-url=https://web.archive.org/web/20131018043013/http://www.atomium-culture.ilsole24ore.com/?p=78 |archive-date=2013-10-18 }}</ref>

While dendrochronology has become an important tool for dating oak panels, it is not effective in dating the poplar panels often used by Italian painters because of the erratic growth rings in poplar.<ref>[{{cite web |url-status=live |url=http://www.nationalgallery.org.uk/paintings/glossary/dendrochronology National|website=The PortraitNational Gallery] {{webarchive|title=Dendrochronology |archive-url=https://web.archive.org/web/20131017120656/http://www.nationalgallery.org.uk/paintings/glossary/dendrochronology |archive-date=2013-10-17 }}</ref>

The sixteenth century saw a gradual replacement of wooden panels by canvas as the support for paintings, which means the technique is less often applicable to later paintings.<ref>[{{cite web |url-status=live |url=http://www.getty.edu/conservation/our_projects/education/panelpaintings/ The |website=Getty Conservation|title=Panel Institute]Paintings Initiative {{webarchive|archive-url=https://web.archive.org/web/20131123200401/http://www.getty.edu/conservation/our_projects/education/panelpaintings/ |archive-date=2013-11-23 }}</ref> In addition, many panel paintings were [[Transfer of panel paintings|transferred onto canvas or other supports]] during the nineteenth and twentieth centuries.

The dating of buildings with wooden structures and components is also done by dendrochronology; [[dendroarchaeology]] is the term for the application of dendrochronology in archaeology. While archaeologists can date wood and when it was felled, it may be difficult to definitively determine the age of a building or structure in which the wood was used; the wood could have been reused from an older structure, may have been felled and left for many years before use, or could have been used to replace a damaged piece of wood. The dating of building via dendrochronology thus requires knowledge of the history of building technology.<ref name="sawyer1993">{{cite book |titlelast1=Sawyer |first1=Peter |author-link1=Peter Sawyer (historian) |url=https://books.google.com/books?id=jGJrXOjYvQgC&pg=PA6 |title=Medieval Scandinavia: from conversion to Reformation, circa 800–1500 |first1last2= PeterSawyer |last1first2= SawyerBirgit |author-link1link2= Peter Sawyer (historian) |first2= Birgit |last2= Sawyer |publisher= [[University of Minnesota Press]] |series= The Nordic Series |volume= 17 |year= 1993 |page= 6 |isbn= 978-0-8166-1739-5 |oclcseries=The 489584487Nordic Series |urlvolume=17 https://books.google.com/books?id|page=jGJrXOjYvQgC&pg=PA66 |url-statusoclc= live489584487 |archive-url= https://web.archive.org/web/20150518110748/https://books.google.de/books?id=jGJrXOjYvQgC&pg=PA6&source=gbs_selected_pages&cad=2 |archive-date= 2015-05-18 |url-status=live}}</ref> Many prehistoric forms of buildings used "posts" that were whole young tree trunks; where the bottom of the post has survived in the ground these can be especially useful for dating.

* The [[Post Track]] and [[Sweet Track]], ancient [[boardwalk|timber trackways]] in the [[Somerset levels]], [[England]], have been dated to 3838 BC and 3807 BC.<ref Name="Current_Archaeology_somerset-levels">{{cite journal|last=Brunning|first=Richard|title=The Somerset Levels|pages=139–143|volume=XV (4)|issue=172 (Special issue on Wetlands)|journal=Current Archaeology|date=February 2001}}</ref>

* [[Navan Fort]] where in [[Prehistoric Ireland]] a large structure was built with more than two hundred posts. The central oak post was felled in 95 BC.<ref name=navan>{{cite book |last= Lynn |first= Chris |title= Navan Fort: Archaeology and Myth |year= 2003 |publisher= Wordwell Books |location= Spain |isbn= 978-1-869857-67-7 }}</ref>

* The [[Fairbanks House (Dedham, Massachusetts)|Fairbanks House]] in Dedham, Massachusetts. While the house had long been claimed to have been built {{circa |1640}} (and being the oldest wood-framed house in North America), core samples of wood taken from a summer beam confirmed the wood was from an oak tree felled in 1637–8, as wood was not seasoned before use in building at that time in [[New England]]. An additional sample from another beam yielded a date of 1641, thus confirming the house had been constructed starting in 1638 and finished sometime after 1641 .<ref>{{cite web|title=A Grand House in 17th-Century New England|url=http://www.fairbankshouse.org/the_house.html|publisher=Fairbanks House Historical Site|access-date=May 27, 2012|url-status=live|archive-url=https://web.archive.org/web/20120316053504/http://www.fairbankshouse.org/the_house.html|archive-date=March 16, 2012}}</ref>

There are many different file formats used to store tree ring width data. Effort for standardisation was made with the development of TRiDaS.<ref>[https://tridas.org/ TRiDaS website]</ref><ref>{{Cite web|last=Jansma|first=Esther|date=30 November 2009|title=TRiDaS 1.1: The tree-ring data standard|url=https://tridas.org/documents/tridas.pdf|url-status=live|access-date=9 February 2021|archive-url=https://web.archive.org/web/20110428011117/http://www.tridas.org:80/documents/tridas.pdf |archive-date=2011-04-28}}</ref> Further development led to the database software Tellervo,<ref>[http://tellervo.org/ Tellervo website]</ref> which is based on the new standard format whilst being able to import lots of different data formats. The desktop application can be attached to measurement devices and works with the database server that is installed separately.<ref>{{cite journal |last1=Brewer |first1=Peter W. |title=Data Management in Dendroarchaeology Using Tellervo |journal=Radiocarbon |date=2014 |volume=56 |issue=4 |pages=S79–S83 |doi=10.2458/azu_rc.56.18320 |bibcode=2014Radcb..56S..79B |doi-access=free|hdl=10150/630521 |hdl-access=free }}</ref>

* [[International Tree-Ring Data Bank]]