Dendrochronology (completed by I. Panyushkina)
IntCal19

a) Sample identifier (Dendro-Lab Key-code): 1971#059
Lab of Tree-Ring Research Archive and Collections, University of Arizona
b) Sample certainly derives from a single tree (Y/N): Y
c) Site: Methuselah Walk site (MW) in the White Mountains, California
37° 22' 45.84'' N; 118° 9' 55.44'' W; 3350 m asl
d) Object type: Remnant log
e) Preservation: excellent, weathered edges
f) Sample type (e.g. core or slice): cross-section
g) Species: Pinus longaeva
h) No of rings: 503
i) Pith (Y/N): N
j) Waney edge: N
k) Bark (Y/N): N
l) Sapwood (Y/N): N
m) Methodology used for dating:
n) The calendar age of the rings was determined with two cross-dating approaches: skeleton plotting and correlation of tree-ring width measurements. Originally the collected specimen was crossdated with skeleton plotting by C.W. Ferguson in 1971, and archived at the LTRR. The specimen’s surface has prick points for the decadal ring count and written dates in astronomical years. Digital catalog of LTRR Collection has records of this specimen as 71#59 and 1971#059. Later the ring widths of this specimen were measured and included into the Methuselah Walk chronology of Bristlecone Pine (LaMarche and Harlan 1973). The ID of this TRW series is #995924 for the period -5924-5422 (503 yrs). See below a copy of COFECHA output with correlation table between this series and the Methuselah Walk master chronology.
For the 14C study, we made new measurements of tree-ring widths for the interval -5559-5371 astronomical years (189 yrs) to confirm the crossdates of rings to be sampled. ID of this TRW series is # 71-59 (see attached 197159 data). A wooden bock was cut from the specimen following the measuring line (see photo at the next page). The sampled specimen was placed back to the archive.
o) Correlation of series #995924 with MW master (LaMarche and Harlan 1973) is 0.69. See line for series # 330
p) Dated individually (Y/N): Y
Cross-dating Steps:
In 2016 for the purpose of 5480 BC excursion study (Miyake et al. 2017, PNAS), C. Baisan and M. Salzer confirmed the dating to be dissected rings with new ring width measurements (C. Baisan) for the interval from -5559 to -5371 (189 yrs). The new measurements were correlated with the Methuselah Walk master chronology. I. Panyushkina supervised the ring cutting and re-checked the target interval dates with the MW master record.
The dates are given in astronomical years. The TRW series includes the Zero Year.
q) Raw ring width series: #197159 series with span -5559 to -5371 (189 yrs) astronomical yrs.
Attached files:
MW 1971-59cof.out - COFECHA output for series #197159 and MW master chronology ca535.rwl (see series #197159 at the position #1). Correlation with the master is 0.67.
MW 1971-59.rwl -File of cross-dated measurements.
Publicly deposited (Y/N): No
Summary of cross-dating history: Wood specimen ID is #71-59 or 1971#59. Tree-ring width series ID is #995924 in the Methuselah Walk master chronology (LaMarche and Harlan 1973), and #197159 series in the 5480 BC excursion study.
p) Remainder of sample is stored in which archive?
LTRR, University of Arizona, Tucson, USA