Dendrochronological Reconstruction Dates Relative sequence Absolute dates Errors

Dendrochronological Reconstruction • Dates – Relative sequence – Absolute dates – Errors in archeological interpretation • Behavior – Construction habits • Environment – Climate in the past 1

Dendrochronology Dating • Does date of wood sample = construction date? 2

Archeological Interpretation of Dates • Outer date predates construction event – Collected dead tree – Collected a bunch of trees, stockpiled – Reuse a beam from old house • 14 th century log used in 1929, Oraibi – Large sites versus distinct sites • Outer date postdates construction event – New log put in during repair – Problem or solution? • Could date repair sequences 3

Date Clustering Saves the Day • Given lots of dates, the date of construction event will be the best cluster of dates – Most frequent date 4

Kin Endeschee 5

• • • Date Clusters Skewed beginning: slow development of site Steep ending: fast abandonment Early dates may be stockpiling, re-use Late dates may be repair beams Requires a lot of dates, replication 6

Cutting Date or Not? • Outermost ring was when tree died • Evidence of cutting date: – Bark, best but not common – Complete outer ring – Beetle galleries – Dark patina veneer 7

Non-cutting Dates • Some number of outer rings lost – Erosion – Shaping – Burning • What to do? – Estimate # of outer rings – Admit non-cutting and leave it – Rely on clustering 8

Behavioral Characteristics • Type of cutting devices – Fire – Stone axes – Metal axes • Repair schedules • Stockpiling, cooperation 9

SW Archeology Sequence • Chaco Anasazi: abandoned by 1130 -1150 – Start of a long period of drought 10

SW Archeology Sequence • Mesa Verde Anasazi: abandoned by 1280 s – In period known as Great Drought 11

SW Archeology Sequence • Kayenta Anasazi: Betatakin, Keet Seel begun by 1250, abandoned by 1300 – Perhaps affected by arroyo formation 12