Conducted by Forrest N. Easley
Forester/Wood Technologist
Consulting Researcher
December 28, 1996
A technical investigation of a wood specimen from the famous Loretto Staircase in the chapel of Our Lady of Light, Santa Fe, New Mexico.
The microscopic technical characteristics of the specimen wood sample from the staircase in the Loretto Chapel in Santa Fe, New Mexico were examined under a variable-power hand lens for general characteristics and under a compound microscope at magnifications varying between 50X to 450X. Both macroscopic and microscopic views of the cross sections and longitudinal samples were observed, and the intracellular characteristics were compared to other similar genera and species in an effort to positively identify this specimen. Comparative date was taken from university level texts used at the College of Forest Sciences, Colorado State University as well as the investigator's long experience in similar studies and reporting.
First, the sample was studied, and after determining its basic characteristics, was placed in its proper position in the "key" list of plants, a key long used by professional botanists, foresters, and colleges of forestry and forest sciences. The wood was determined to be "conebearing" and "evergreen" with an "unjointed woody stem."
A further step to a more exacting identity required the examination of the internal structure of the cellular arrangement and function. As can be seen in the following descriptive key, only one genus is indicated: PICEA.
The key presents comparative data that includes the features of related species in an effort to show any relationship of the sample specimen under study to the known tree species named and described in approved and professionally accepted documents and publications.
As can be seen, no specific species is indicated, but, instead a wood that fits between Picea sitchensis and Picea engelmannii is described.
Therefore, I, the investigator, since this specimen is of a wood heretofore unknown, hereby assign to the thus-far unnamed species within the genus Pinacae Picea the following names:
Suggested scientific name: Pinacae Picea josefii Easley
Suggested common name: Loretto Spruce
Technical Description
- Wood non-porous (no vessels). Cross sections consist of radial rows of tracheids distinctly visible; rays are present and appear distinct to the naked eye.
- Resin canals present. Longitudinal canals appear as small openings mostly in the ourter portion of the late wood. Transverse canals included in some rays then appear much larger, but aparse, and under a microscope appear as small donuts with a dark outer margin. This is typical to the Picea genus (spruces).
- Resin canals numerous, unevenly distributed in the outer portion of every growth ring, generally visible to the naked eye, as light-colored dots or small openings; conspicuous with a hand lens. Epithelial cells are thin-walled.
- Tangential surface WAVY (not dimpled or undimpled as in other Picea species). Outer margin of growth increment not distorted.
- Wood very strong, light to moderately heavy. Bands of late wood usually narrow and pinkish in color. Early wood light tannish to light brown. Late wood forming a band 5 to 10 cells in width.
- Heartwood light reddish to light brown. Resin canals small, inconspicuous or not visible to the naked eye. The majority of the resin canals are with a tangential diameter less than 100 um, no visible ray tracheid dentations or, at least, not prominent, not extending across the cell.
- Ray parenchyma cross-field pits in early wood small, and occur fewer than 5 per cross-field.
- Late wood not pronounced. Transition from early wood to late wood is gradual but noticeable.
- Heartwood distinct but gradual. Wood as an entity is light brownish to pinkish tinge at the late wood and is semi lustrous, fine textured, and the tangential (split) surface is not dimpled, but wavy.
- Longitudinal tracheids are more or less square in cross section. Average dimension of 20 to 25 um on each side when viewed in a radial section of wood under a microscope. No other spruce has "square shaped cells."
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