The Structural Conservation of Panel Paintings

identification therefore requires at least a general familiarity with the

anatomical characteristics and nomenclature ofwood as well as the avail-

ability of suitable reference material for the woods being considered.

It is beyond the scope of this article to present a complete treatise

onwood anatomy and the identification of all woods that might be

encountered in painted panels. Instead, an attempt will be made to provide

a primer of the basics of wood anatomy along with routine approaches

and techniques for wood identification. In addition, a summary of perti-

nent features and the identification process is presented for a selection of

woods—a sampler ofsorts—most commonly found in painting panels.

Taxonomy, the science of classifying living things, provides a systematic

approach to the study of wood tissue, as closely related trees can be

expected to have similarities of anatomical features. Wood identification

therefore finds its foundation in taxonomy, and narrowing the identity of

an unknown piece ofwood to its tree species follows closely the taxo-

nomic network. In taxonomic classification, woody plants of tree sizes

in temperate regions of the world are found principally in either of two

classes, the gymnosperms, which include the conifers, or softwoods,and

the angiosperms, wherein the hardwoodsoccur. In turn, classes are divided

into orders, families, genera (singular: genus), and, finally, species (Table 1).

Each species is designated by a scientific name, a Latinized, itali-

cized binomial termcomprising its genus name followed by its species

name, or epithet. For example, the species we know by the common name

ofblack poplar has the scientific name ofPopulus nigra—Populusindicating

the generic name for all poplars and nigrathe epithet for the black poplar

species. Botanical names are universally accepted among scientific disci-

plines, and their usage is therefore preferred in order to prevent the confu-

sion that may result when a species has a number of common or local

names in a particular language. For example, Norway spruce, Picea abies,

is also known in English as European spruce or simply as whitewood.

The ultimate objective in wood identification is to determine the

species oftree from which a particular piece ofwood originated, and it is

therefore always proper and desirable to use the species name to designate

a piece of its wood. Unfortunately, the woods of species within a genus

(such as, for example, the poplars) are commonly so similar that they

lackdistinguishing features and cannot be separated. In this situation the

scientific name ofthe genus is given, followed by the designation “sp.”

(plural: spp.), printed in roman (not italic) script. As an example, a painting

panel might, in fact, be black poplar but can perhaps only be identified as

poplar; it is therefore designated Populussp.

Wood identification is based primarily on anatomical structure and should

proceed with the awareness that wood is a composite mass of countless

numbers of cells. These cells were produced by cell division of the cam-

bium, the layer of reproductive tissue beneath the tree’s bark, and the

cy clic variations of this growth process are recognizable in most woods as

growth rings. Each wood cell has an outer wall that surrounds an internal

cavity. In the living tree, a cell cavity may contain a living protoplast, or at

least some liquid sap, whereas in the wood found in painted panels, the

Wood Anatomy: The Basis

for Identification

Woods and Their Names

22 Hoadley