Browsing Tree-Ring Research, Volume 71, Issue 2 (Jul 2015) by Title
Now showing items 7-8 of 8
Tree-Ring Investigation of Holocene Flood-Deposited Wood from the Oneida Lake Watershed, New York StateGlacial deposition and fluvial/lacustrine sedimentation interact over terrains in central New York State to preserve a history of geological and hydrological events as well as hydroclimatic transitions. The lower reach of Fish Creek draining the eastern watershed of Oneida Lake, NY, is an area with prominent wood remains. This study explores a collection of 52 logs encased in organic-rich deposits exposed by bank erosion at three locations along Fish Creek near Sylvan Beach, NY, with respect to radiocarbon ages, species, and the crossdating potential of tree rings. Radiocarbon ages and successful tree-ring crossdating document what we interpret as seven major hydrologic episodes ca. 10 ka (i.e. ca. 10,000 cal yr BP), 7.4 ka, 6.8 ka, 6.4 ka, 5.5 ka, 3.1 ka and 2.2 ka cal BP, during which channel aggradation and tree burial may have been associated with abruptly increased flood frequency and/or high water tables. This pilot study establishes four floating tree-ring records:  early Holocene hemlock (Tsuga), mid-Holocene  walnut (Juglans sp.) and  sycamore (Platanus), and  late Holocene elm (Ulmus sp.), with sample sizes of 8-14 series of 55-135 years length. Despite the complexity of distribution of radiocarbon ages at each site, the wealth of well-preserved wood demonstrates great promise for understanding the paleoflood history of the Oneida watershed by documenting the magnitude, location, and timing of floods. Further additional systematic sampling can add and strengthen tree-ring dating and tree-ring based flood records, confirm results, and contribute to the Holocene hydrological history of the region. Copyright © 2015 by The Tree-Ring Society.
Trimming and Planing Rough-Cut Wood for Efficient Dendrochronological Sample Preparation and StorageWood samples larger than increment cores collected for tree-ring studies are often obtained using chainsaws and, less frequently, 2-person crosscut saws. Saw marks on cross-sectional wood samples can be quite deep and uneven, and sanding rough-cut wood cross-sections is inefficient in terms of processing time and wear on sanding belts. Trimming rough-cut wood samples with a band saw or treating with a surface planer creates a smoother initial surface for sample sanding and polishing. Sample trimming with a band saw or surface planer is also useful for post-analysis archiving and wood storage, when excess wood can be removed and smaller samples entered into storage. Band saw and surface planer safety techniques are also discussed. Copyright © 2015 by The Tree-Ring Society.