John Hart, PhD, New York State Museum

1. Learning from Pottery:
Maize History in Central New York
by
John P. Hart
Research & Collections Division
New York State Museum

2. Traditionally…
it was thought that maize was adopted in central New
York around A.D. 1000 based on the recovery of maize
macrofossils over the course of much of the twentieth
century.

6. Charred Cooking residue

8. Research over the last decade has
shown that various microfossils can be
recovered from charred cooking
residue:
• Phytoliths
• Starch
• Lipids
The residues can also be AMS dated
providing direct association of dates with
the microfossils.

9. Maize & Phytoliths

11. Rondel phytoliths recovered
from cooking residue

12. Indigenous Eastern N.
Grass Am. Maize
Indigenous Grass 15 0
Eastern N. Am. Maize 0 24
Residue 4 17
Archaeological Maize 0 9
Mexican Maize 0 29
John P. Hart, and R. G. Matson 2009. The Use of Multiple Discriminant Analysis in Classifying Prehistoric Phytolith
Assemblages Recovered from Cooking Residues. Journal of Archaeological Science 36:74-83.

13. Results of Cooking Residue Analyses
Site Cal 2σ range (median probability)1 Phytolith results
Scaccia 1256 (1096) 998 B.C. Squash
Vinette 1 790 (638) 519 B.C. No phytoliths
Vinette 1 399 (296) 208 B.C. Maize
Felix Zone 5 376 (285) 197 B.C. Squash?
Vinette 2 39 B.C. A.D. (40) 1192 Maize
Wickham 2 A.D. 263 (391) 4302 No phytoliths
Simmons A.D. 349 (448) 540 Wild rice
Westheimer 2 A.D. 393 (475) 544 Maize
Felix Zone 4 A.D. 432 (510) 5752 Maize
Fortin 2 zone 3 A.D. 434 (557) 6132 Maize, squash, sedge
Wickham 3 A.D. 568 (619) 6552 Maize, wild rice?, squash, sedge
Kipp Island 3 A.D. 600 (630) 6552 Maize, wild rice, squash, sedge
Simmons A.D. 594 (645) 683 Maize
Felix Zone 4 A.D. 608 (646) 6682 Maize, squash?
Wickham 3 A.D. 681 (792) 889 Wild rice, maize?, sedge
Hunters Home A.D. 718 (805) 8802 Maize, wild rice, squash
Street A.D. 892 (994) 1117 Maize
Klock A.D. 1327 (1431) 1475 Maize
Garoga A.D. 1417 (1465) 1626 Maize
Smith-Pagerie A.D. 1408 (1448) 1618 No phytoliths
1
CALIB 5.0 (Stuiver et al. 1998).
2
Pooled mean of multiple dates (Ward and Wilson 1978)
Hart, John P., Hetty Jo Brumbach, and Robert Lusteck. 2007. Extending the Phytolith Evidence for Early Maize (Zea
mays ssp. mays) and Squash (Cucurbita sp.) in Central New York. American Antiquity 72:563-583.

15. A.D. 500
250 B.C.
150 B.C. –
A.D. 500

16. Cooking Residues
and Isotopes

17. • Maize is a C4 pathway with an average δ13C of
around –11.2‰.
• C3 pathway plants have an average δ13C of
around –27.0‰.
• Analysts had assumed a linear relationship
between the proportion of maize cooked and
residue δ13C. The higher the proportion of maize
the less negative should be the residue δ 13C.
• Some analysts had suggested a δ13C value ≥-24
indicated maize presence.
• The recovery of maize phytoliths from residues
with highly negative δ13C raised doubts about this
assumption.

18. Experimental Residues 1

19. 0 10 20 30 40 50 60 70 80 90 100
-5
-10
-15
δ13C
-20
-25
-30
-35
Percent Maize
Comparison of experimental δ13C values to a threshold for maize presence of -22‰
(adjusted for industrial era atmospheric carbon). (X= deer meat and maize flour, ■
and ▲ = wild rice and maize flours, ○ = Chenopodium and maize kernels).
Hart, John P., William A. Lovis, Janet K. Schulenberg, and Gerald R. Urquhart. 2007. Paleodietary Implications from
Stable Carbon Isotope Analysis of Experimental Cooking. Journal of Archaeological Science 34:804–813.

20. • The amount of carbon in resources varies.
• The δ13C value depends on the amount of
carbon contributed to residue formation by
each resource.

21. 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100
-5 0
-10 -5
-15 -10
Model Model
-20 -15
δ13C
Minimum
δ13C
Minimum
Maximum Maximum
-25 -20
Observed Observed
-30 -25
-35 -30
-40 -35
Percent Maize Percent Maize
a b
0 10 20 30 40 50 60 70 80 90 100
0
-5
Model vs. observed for two-part
-10
mixes of maize flour with (a)
-15
Model
Chenopodium flour, (b) wild rice
δ13C
Minimum
-20
Maximum
Observed
flour, (c) deer meat.
-25
-30
-35
Percent Maize
c

22. a) Dry Maize b) Green Maize
0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100
0 0
-5 -5
-10 -10
-15 Model -15 Model
δ13C
δ13C
Minimum Minimum
-20 Maximum -20 Maximum
-25 -25
-30 -30
-35 -35
Percent Maize Percent Maize
a b
Model δ13C values of mixtures of hypothetical slurries of equal parts deer,
chenopod, and wild rice mixed with increments of (a) dry maize and (b) green
(wet) maize.

23. Conclusions Experiment 1
• It is not possible to interpret δ13C values on
any given residue without already knowing
what was cooked in the pot.
• A highly negative δ13C value on a residue
does not indicate maize was not cooked in
a pot.

24. Experimental Residues 2

25. Bulk δ13C values by percent maize for 60-minute suspension/solution samples (●=deer and hominy,
▲=hominy and wild rice, ■= maize kernel and wild rice, ♦ = corn meal and wild rice). The horizontal
line is the -22‰ cut point following Morton and Schwarcz (2003) as the bulk δ13C value at which
maize is taken to be represented in a residue adjusted for modern, industrial-era average δ13C
values for C3 and C4 plants
Hart, John P., Gerald R. Urquhart, Robert S. Feranec, and William A. Lovis. 2009. Nonlinear Relationship Between Bulk δ 13C and
Percent Maize in Carbonized Cooking Residues and the Potential of False Negatives in Detecting Maize. Journal of
Archaeological Science 36:2206–2212.

26. Model (lines) vs. observed (points) δ13C values for 60% wild rice and 40% maize mixture
(open symbols=suspension/solution, solid symbols=foam; triangles=kernels,
diamonds=corn meal, squares=hominy; lines=model; solid=corn meal, dotted= kernels,
dashed=hominy).

27. Conclusions Experiment 2
• The amount of carbon contributed by a resource
to a residue depends on the mobilization of
carbon from each resource, which depends on:
– time and
– the form of maize being cooked (whole kernel,
hominy, meal.
• Whole kernel maize and hominy are masked by
the C3 resource, whereas corn meal masks the
C3 resource.

28. Isotope Chronology

30. r = .675 (p<<.005)
r = .793 (p<<.005)
Hart, John P., William A. Lovis, Robert J. Jeske, and John D. Richards. 2012. The Potential of Bulk δ 13C on Encrusted
Cooking Residues as Independent Evidence for Regional Maize Histories. American Antiquity 77:315–325.

31. Southeastern Wisconsin/Northeastern Illinois

32. Lower Michigan Peninsula

33. Pottery Technology,
Isotopes, and Chronology

34. • For any given pottery vessel size, thinner
walls are:
– more efficient conductors of heat, and
– less subject to failure as a result of thermal
shock.

36. 0 .9
0 .8
Average Wall Thickness (mm)/Diameter (cm)
0 .7
0 .6
0 .5
0 .4
0 .3
0 .2
0 .1
0 .0
-1 4 0 0 -1 2 0 0 -1 0 0 0 -8 0 0 -6 0 0 -4 0 0 -2 0 0 0 200 400 600 800 1000 1200 1400 1600 1800
C a lib ra t e d D a t e (B . C . / A . D . )
A scatter plot of average wall thickness in mm divided
by diameter in cm by time. The solid line is LOWESS
smoothing, and the dashed line is DWLS smoothing.
Hart, John P., and Hetty Jo Brumbach. 2009. On Pottery Change and Northern Iroquoian Origins: An Assessment from the Finger
Lakes Region of Central New York. Journal of Anthropological Archaeology 28:367-381.

37. δ13C and Pottery
• Bulk stable carbon isotope (δ13C) values
were obtained on 48 residues from 14
sites with components dating from ca. cal.
300 B.C. to A.D. 1550 in central New
York.
• Thickness adjusted for vessel diameter
was for the 227 sherds from 17 sites with
components dating from ca. cal. 300 B.C.
to A.D. 1600.

38. General site locations. Black dots denote sites producing both bulk δ13C and wall
thickness data. Grey dots indicate sites producing only wall thickness data.

39. r = - .924 (p<<.005)
r = –0.924, p<<0.005
r = - .960 (p<<.005)
r = –0.960, p<<0.005
Distance weighted least squares (DWLS) trend lines for adjusted pottery wall thickness (solid line) and bulk
δ13C values by calibrated AMS median probability dates on charred cooking residues.
Hart, John P. 2012. Pottery Wall Thinning as a Consequence of Increased Maize Processing: A Case Study from Central New
York. Journal of Archaeological Science (2012): DOI:10.1016/j.jas.2012.06.006.

40. Conclusions
• Maize was adopted in central New York by
cal. 300 B.C.
• Maize began to become an important
resource in regional diets 500 years later,
around ca. cal. A.D. 200.
• Single lines of evidence cannot be used to
build robust regional histories of maize
use.

41. Collaborators
• Hetty Jo Brumbach (University at Albany)
• Robert S. Feranec (New York State Museum)
• Robert J. Jeske (University of Wisconsin-Milwaukee)
• William A. Lovis (Michigan State University)
• Robert Lusteck (University of Minnesota)
• R. G. Matson (University of British Columbia)
• John D. Richards (University of Wisconsin-Milwaukee)
• Janet K. Schulenberg (The Pennsylvania State University)
• Robert G. Thompson (University of Minnesota)
• Gerald R. Urquhart (Michigan State University)