Fig. 1 Tasteful pile of wood.
The Journey
Methods and Analyses:
Four series were measured from wood cross sections from Miller House. Four series were measured from each of four cross sections of wood — two Oak and two Ash. The cores were prepared and sanded; annual rings were counted, measured to the nearest 0.001 mm, and then cross-dated using standard dendrochronological techniques (Fig. 4). Multiple cores were measured from Miller House to determine annual ring correlation along differing cross sectional radii. All series from a site are then cross-dated against each other, developing a “floating” site chronology before cross-dating with the calendar dated Southwestern Ohio regional series. Cross-dating shows a strong correlation with a regional master chronology from Southwest Ohio.
Which series from which houses were successfully calendar dated? Which series provided true outer rings (which are important in determining the year of felling)?
The two cross sections of oak from the Miller House mantle were successfully cross-dated. There was an overlap of 20 years between the oak sample containing the bark and the oak sample from the mantle. Miller Farmhouse creates a 240 year chronology spanning the years 1573-1812 A.D. This data places the construction date for Miller Farmhouse around the year 1812. The data from these structures is instrumental in expanding our knowledge of the chronology not only of Franklin, but also of the greater Southwestern Ohio region
The small core from the mantle of Miller Farmhouse has a full outer ring, however the small holes in the middle of the figure (Fig. 2) illustrate that the tree must have been on the verge of a non-growing season, since they’re new enough to not be filled in like the remainder of the porous areas on the wood.
Figure 2. Image of the outer rings of a large oak from the mantle of Miller House that was used for dating.
Figure 3. Graph of Tree Ring widths versus years. Ring widths vary based on environmental conditions like precipitation, soil nutrients, and sunlight. The fluctuations within the graph reflect fluctuations in environmental conditions at the associated date.
Figure 4. Image that shows how tree wing widths from different trees and tree cores are correlated in order to build a tree ring chronology and date the wood.
This diagram illustrates the principles of cross-dating. Samples are taken from very old, living, and recently dead trees. The ring-width patterns are then correlated and matched to long dead trees. Once enough cores are correlated, a chronology can be formed.
