Evidence of Prehistoric Cultivation of Douglas-Fir Trees at Mesa Verde

1965 ◽  
Vol 19 ◽  
pp. 57-64 ◽  
Author(s):  
Robert F. Nichols ◽  
David G. Smith
Keyword(s):  
Root System ◽  
Tree Ring ◽  
Stone Tools ◽  
Douglas Fir ◽  
Single Root ◽  
Mesa Verde ◽  
12Th Century ◽  
Old Trees ◽  
Short Time

AbstractThree trees which began growing in the 12th century lean in a manner not characteristic of neighboring Douglas-firs and have tree-ring patterns showing changes that do not appear to reflect climatic influences. Two old trees, now dead, have limb stubs that were cut by stone tools. It is possible the prehistoric Indians cultivated trees so that in a relatively short time a single root system would produce several limbs suitable for use as construction timbers.

The Biological Model for Paleoclimatic Interpretation of Mesa Verde Tree-Ring Series

1965 ◽  
Vol 19 ◽  
pp. 101-121 ◽  
Author(s):  
Harold C. Fritts ◽  
David G. Smith ◽  
Marvin A. Stokes
Keyword(s):  
Tree Ring ◽  
High Temperatures ◽  
Ring Width ◽  
Douglas Fir ◽  
Biological Model ◽  
Tree Ring Chronology ◽  
Mesa Verde ◽  
Pinyon Pine ◽  
Utah Juniper ◽  
Low Precipitation

AbstractRing-width chronologies in Douglas-fir, pinyon pine, and Utah juniper show some distinctly different characteristics and exhibit highly predictable relationships with variations in climate. Narrow rings in Douglas-fir are largely the result of low precipitation and high temperatures of the previous June, low precipitation during August through February, low precipitation and low temperatures during March through May, and low precipitation and high temperatures of the current June. Narrow rings in pinyon pine are largely a function of low precipitation from October through May, but high July temperatures near the end of the growing season may also exert an influence. Narrow rings in Utah juniper are the result of low precipitation and high temperatures during the previous October through November, low precipitation during December through February, and low precipitation and high temperatures during March through May. A biological model for these relationships is proposed. The tree-ring chronology from A.D. 1273 through 1285 exhibits a clearly defined drought which exceeds in length and intensity any dry period occurring since A.D. 1673. A comparison of the chronologies from species which are influenced differently by summer precipitation indicates that during this period both summers and winters must have been dry. However, the A.D. 1273-1285 drought at Mesa Verde was surpassed by six other droughts of greater intensity during the period A.D. 500–1300. The A.D. 1273–1285 drought may be only one of several factors in a chain of events which led to the decline of prehistoric population in the Mesa Verde.

scholarly journals Dynamics of cavitation in a Douglas-fir tree-ring: transition-wood, the lord of the ring?

2014 ◽  
Vol 1 ◽  
pp. e005 ◽  
Author(s):  
Guillermina Dalla-Salda ◽  
María Elena Fernández ◽  
Anne-Sophie Sergent ◽  
Philippe Rozenberg ◽  
Eric Badel ◽  
...  
Keyword(s):  
Water Stress ◽  
Tree Ring ◽  
Wood Density ◽  
Douglas Fir ◽  
X Ray ◽  
Conductive Surface ◽  
Lower Transition ◽  
Successive Initiation ◽  
Old Trees ◽  
Transition Wood

The objective of this work was to investigate the dynamics of embolism formation within a Douglas-fir tree-ring. Four resistant and four vulnerable 10-year-old trees were selected among 50 trees, based on their P50. Stem samples, taken next to those used to obtain the vulnerability to cavitation curves, were collected and submitted to increasing positive pressures, in order to simulate increasing tension caused by water stress in the xylem. Then the conductive surface of the samples was stained and scanned and the images were analyzed. X-ray microdensity profiles were obtained on the same samples. The microdensity profiles of the 2011 ring were analyzed in three parts, earlywood, transition-wood and latewood. The dynamics of embolism propagation was observed separately in these three parts. Our results showed that the initiation and the propagation of the cavitation follow a discrete trend, with at least two successive initiation events: first cavitation initiates and propagates rapidly in the latewood. Then, a second cavitation event begins and spreads in the earlywood and eventually propagates to the transition-wood, which remains the last conductive part in the ring before full embolism. We observed that resistant to cavitation trees showed lower transition-wood density than vulnerable to cavitation trees. 

The Curious Douglas-Fir (Pseudotsuga Menziesii) Trees in Schulman Grove, Mesa Verde National Park, Southwestern Colorado, USA

2021 ◽  
pp. 1-20
Author(s):  
Stephen E. Nash ◽  
Ronald H. Towner ◽  
Jeffrey S. Dean
Keyword(s):  
Forest Management ◽  
Tree Ring ◽  
Pseudotsuga Menziesii ◽  
National Park ◽  
Douglas Fir ◽  
The West ◽  
West Side ◽  
Mesa Verde ◽  
Ancestral Puebloan ◽  
Tree Manipulation

In 1954, archaeologists James Allen Lancaster and Don Watson and dendrochronologist Edmund Schulman asserted that a small grove of Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco var. glauca [Beissener] Franco) trees in Navajo Canyon on the west side of Chapin Mesa in Mesa Verde National Park contained evidence of stone-axe-cut tree limbs. In 1965, archaeologists Robert Nichols and David Smith published an article entitled “Evidence of Prehistoric Cultivation of Douglas-Fir Trees at Mesa Verde,” in which they supported the Lancaster/Watson/Schulman assertion with tree-ring dates from suspected stone-axe-cut limbs. If correct, Nichols and Smith (1965) document the only trees in the entire U.S. Southwest that contain ancient stone-axe-cut stubs and evidence of precolumbian forest management. Rather than accept their interpretations at face value, we attempt to replicate their dates through the (re)analysis of archived and recently collected tree-ring samples, and through a controlled analysis and comparison of archived and published records. We could not confirm their results, and we have no option but to reject their claim that Schulman Grove contains evidence of precolumbian tree manipulation by Ancestral Puebloan inhabitants of Mesa Verde.

Las Madres in the Light of Anasazi Migrations

1964 ◽  
Vol 29 (4) ◽  
pp. 449-454 ◽  
Author(s):  
Bertha P. Dutton
Keyword(s):  
New Mexico ◽  
Tree Ring ◽  
Ceramic Materials ◽  
Burial Practices ◽  
Mesa Verde ◽  
Lithic Artifacts ◽  
Regional Types

AbstractThe site of Las Madres near Galisteo, New Mexico, has yielded a provocative array of culture traits, each deviating from recognized Anasazi norms. Regional types of black-on-white sherds were encountered, accompanied by variants. Few Glaze I Red sherds appeared on the surface, but excavations revealed them in considerable quantity from top to bottom; there are fewer Glaze I Yellow and Polychrome representations. Tree-ring dates and ceramic materials indicate occupation from the late 1200's to about 1370. A transitional situation is suggested by bird bones, pottery variations, absence of formalized building plan, eclectic burial practices, and lithic artifacts. There is no evidence of direct migration of Mesa Verde people into the Galisteo region.

Heartwood decay resistance by vertical and radial position in Douglas-fir trees from a young stand

1999 ◽  
Vol 29 (12) ◽  
pp. 1993-1996 ◽  
Author(s):  
Barbara L Gartner ◽  
Jeffrey J Morrell ◽  
Camille M Freitag ◽  
Rachel Spicer
Keyword(s):  
Leaf Area ◽  
Decay Resistance ◽  
Douglas Fir ◽  
Radial Position ◽  
Sapwood Area ◽  
Decay Fungus ◽  
Postia Placenta ◽  
Young Stand ◽  
Wide Range ◽  
Old Trees

Heartwood durability of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) was studied as a function of vertical and radial position in boles of trees with a wide range of leaf area/sapwood area ratios. Six 34-year-old trees were harvested from each of three plots established 14 years before: very dense, thinned, and thinned and fertilized. Heartwood samples from three radial positions and five heights were incubated with the decay fungus Postia placenta (Fr.) M. Larsen et Lombard. There were no significant differences in wood mass loss (decay resistance) by vertical or radial position. One could expect that trees with high leaf area/sapwood area could have the carbon to produce heartwood that is more resistant to decay than trees with lower leaf area/sapwood area. However, we found no relationship between leaf area above node 20, sapwood area there, or their ratio, and the decay resistance of outer heartwood at that node. These results suggest that, for young Douglas-fir trees, heartwood durability does not vary with position in the bole or with environments that alter the tree's balance of sapwood and leaf area. We suggest that young stands may thus be robust with respect to the effect of silvicultural regimes on heartwood durability.

scholarly journals Linkages between Climate, Radial Growth and Defoliation in Abies pinsapo Forests from Southern Spain

Forests ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 1002
Author(s):  
Rafael M. Navarro-Cerrillo ◽  
Antonio Gazol ◽  
Carlos Rodríguez-Vallejo ◽  
Rubén D. Manzanedo ◽  
Guillermo Palacios-Rodríguez ◽  
...  
Keyword(s):  
Tree Ring ◽  
Radial Growth ◽  
Early Summer ◽  
Southern Spain ◽  
Tree Age ◽  
Severe Drought ◽  
Recent Climate ◽  
Tree Ring Data ◽  
Abies Pinsapo ◽  
Old Trees

Systematic forest networks of health monitoring have been established to follow changes in tree vigor and mortality. These networks often lack long-term growth data, but they could be complemented with tree ring data, since both defoliation and radial growth are proxies of changes in tree vigor. For instance, a severe water shortage should reduce growth and increase tree defoliation in drought-prone areas. However, the effects of climatic stress and drought on growth and defoliation could also depend on tree age. To address these issues, we compared growth and defoliation data with recent climate variability and drought severity in Abies pinsapo old and young trees sampled in Southern Spain, where a systematic health network (Andalucía Permanent Plot Network) was established. Our aims were: (i) to assess the growth sensitivity of old and young A. pinsapo trees and (ii) to test if relative changes in radial growth were related with recent defoliation, for instance, after severe droughts. We also computed the resilience indices to quantify how old and young trees recovered growth after recent droughts. Wet-cool conditions during the prior autumn and the current early summer improved the growth of old trees, whereas late-spring wet conditions enhanced the growth of young trees. Old trees were more sensitive to wet and sunny conditions in the early summer than young trees. Old and young trees were more responsive to the Standardized Precipitation-Evapotranspiration Index drought index of June–July and July–August calculated at short (one–three months) and mid (three–six months) time scales, respectively. Old trees presented a higher resistance to a severe drought in 1995 than young trees. A positive association was found between stand defoliation and relative growth. Combining monitoring and tree ring networks is useful for the detection of early warning signals of dieback in similar drought-prone forests.

Recent growth increases in old-growth longleaf pine

1993 ◽  
Vol 23 (5) ◽  
pp. 846-853 ◽  
Author(s):  
D.C. West ◽  
T.W. Doyle ◽  
M.L. Tharp ◽  
J.J. Beauchamp ◽  
W.J. Platt ◽  
...  
Keyword(s):  
Tree Ring ◽  
Longleaf Pine ◽  
Biomass Accumulation ◽  
Severity Index ◽  
Drought Severity ◽  
Tree Ring Chronology ◽  
Annual Increment ◽  
Old Growth ◽  
Tree Ring Data ◽  
Old Trees

Longleaf pine (Pinuspalustris Mill.) tree-ring data were obtained from an old-growth stand located in Thomas County, Georgia. The tree-ring chronology from the pine stand is composed of a collection of cores extracted from 26 trees ranging in age from approximately 100 to 400 years. These cores were prepared, dated, and measured, and the resulting data were examined with dendrochronological and statistical techniques. Beginning in approximately 1950 and continuing to the present, annual increments of all age classes examined in this study have increased, resulting in an average annual ring increment approximately 40% greater in 1987 than in 1950. When compared with expected annual increment, the increase for 100- to 150-year-old trees is approximately 45%, while the increase for 200- to 400-year-old trees is approximately 35%. In terms of stand-level aboveground biomass accumulation, the increased growth has resulted in approximately 5% more biomass than expected. The increased growth cannot be explained by disturbance; stand history; or trends in precipitation, temperature, or Palmer drought severity index over the last 57 years. Increased atmospheric CO2 is a possible explanation for initiation of the observed trend, while SOx and NOx may be augmenting continuation of this phenomenon.

How Tree Roots Gather Oxygen from Soil for Energy Supply by Respiration

1997 ◽  
Vol 52 (11-12) ◽  
pp. 824-827 ◽  
Author(s):  
Hans-Joachim Frick ◽  
Dietrich Woermann ◽  
Wolfgang Grosse
Keyword(s):  
Gas Exchange ◽  
Root System ◽  
Gas Flow ◽  
Molar Mass ◽  
Soil Surface ◽  
Alnus Glutinosa ◽  
Tree Roots ◽  
Convective Gas Flow ◽  
Old Trees ◽  
Convective Volume

Abstract The gas exchange between the root system of the European alder (Alnus glutinosa (L.) Gaertn.) and the surrounding soil is studied using four-year-old trees. For the experiments the root system connected to its stump is exposed to gases of different molar mass. The stump is cut above the soil surface and in contact with the external atmosphere. A net convective volume flow of gas from the soil into the roots and out of the stump is observed if the mean molar mass of the gas present in the soil is lower than that present in the intercellular space of the roots. The direction of the convective gas flow can be reversed by increasing the molar mass of the gas present in the soil. These phenomena are governed by Graham 's law of diffusion. They demonstrate the importance of gas convection for the gas exchange in tree roots.

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