Although plant fiber artifacts often formed a very substantial portion of the total ‘industrial' output of both ethnographic and prehistoric populations, the archaeological recovery of these items, as noted above, is directly conditioned by circumstances of preservation. Space precludes a detailed discussion of recovery or conservation protocols, but some commentary on these topics is warranted.
Dry Sites
In dry caves and rockshelters, fiber artifacts may be notably abundant and their condition is generally excellent. Only minor modifications in the basic excavation and screening procedures are usually necessary to ensure consistent recovery. If employed at all, large, heavy excavating tools (e. g., shovels, pick-mattocks) should be abandoned in zones containing fiber artifacts because they can seriously damage or even destroy specimens. For the same reason, sharp-edged trowels should not be employed in sorting screened materials (see Caves and Rockshelters).
Specimens encountered during the excavation and screening operations usually require only careful packaging in rigid plastic or fiberboard containers with suitable packing material (e. g., styrofoam, shredded paper, etc.) to ensure their arrival intact in the laboratory. Naturally, detailed provenience data must be recorded for all fiber specimens as well as all associated artifactual and nonartifactual materials. If possible, specimens should be photographed in situ and mapped in plan along with any associated items before removal to ensure that details of construction are preserved if the specimens should be lost or destroyed during excavation or transportation. All fiber specimens, however minute, should be saved for analysis.
Even in a more or less dry site, basketry, textiles, cordage, and other perishables may have suffered from periodic exposure to moisture (notably in the deeper levels) or may be badly worn, charred, or gnawed by rodents. Any of these conditions can render the specimens too friable for transport until they have been treated. Occasionally, deterioration is so great that field stabilization must be performed before removal from the soil matrix.
Wet Sites
Included here are all sites, sheltered or exposed, that are subject to periodic rain, flooding, or the movement of ground water. This category also subsumes sites that are permanently waterlogged or submerged, or that are permafrozen. The survival of fiber artifacts in any form from such sites is considerably less probable than from dry sites and its condition is usually far worse.
In most open sites, fiber artifacts are generally preserved only in a charred or incinerated state or in the form of negative impressions, which may not be recognized by the excavators as perishable artifacts. Thousands of pieces of wholly or partially incinerated basketry, textiles, cordage, and other perishables, as well as many more thousands of impressions, have doubtless been lost simply because they were unexpected, unrecognized, or both.
As a general guideline, it is always best to presume that charred or incinerated fiber artifacts may be encountered in any site and therefore to use excavation procedures that maximize chances of discovery/ recovery. Charcoal or charcoal/ash concentrations and ‘stained areas’ should be excavated cautiously and scrutinized frequently and closely. Any phenomena should be presumed to be potential fiber artifacts until proven otherwise and appropriate measures taken to ensure their recovery. Occupation ‘floors’ or surfaces, pits, and hearths should also be investigated carefully for basketry impressions which are often even more difficult to recognize than charred remains.
It cannot be overemphasized that success in recovering fiber artifacts from most open sites depends almost entirely on recognizing evidence. The excavator must remember that distorted, carbonized, sediment-encrusted remnants bear little or no resemblance to complete, well-preserved specimens. In fact, there is no substitute for experience in this type of identification.
When a specimen suspected of being an incinerated or carbonized fiber artifact is encountered, extreme care should be exercised in exposing it. If it retains any structural integrity, it may simply be tediously uncovered with delicate instruments (e. g., dental probes, biological probes, needles, bamboo slivers), augmented where appropriate by soft camel’s hair brushes or judicious use of compressed-air delivered via canister. If incinerated specimens are too fragile to be separated from the soil matrix without severe damage, surface and/or internal consolidation may be required. In extreme cases, the surrounding soil matrix must be consolidated and the specimen removed en bloc.
Other wet-site conditions present different problems. The successful extraction of basketry or other fiber artifacts preserved through contact with metal does not usually require any special procedures. Normal caution in excavating and packing the metal fragments for transport should permit recovery of any adhering perishables.
Permanently or intermittently waterlogged or per-mafrozen sites require highly specialized recovery techniques. The removal of specimens from very muddy contexts is best accomplished with hydraulics or a combination of hydraulics and more conventional techniques. High-velocity water sprays or jets must be carefully monitored to prevent the pressure of the water from exceeding the surface strength of the specimens and thereby causing irreparable damage. If properly controlled, the careful use of hydraulics will effectively and safely separate fiber artifacts from a muddy matrix (see Sites: Waterlogged).
Plant fiber artifacts from permanently waterlogged, submerged, and permafrozen contexts must be approached with extreme care. While such specimens may be removed intact with little difficulty, others may necessitate complex extraction procedures. All such specimens require special handling after excavation. Although they often give the illusion of being structurally strong, waterlogged specimens cannot bear excessive handling and will lose structural integrity through rapid drying. After excavation, every effort must be made to ensure that waterlogged or permafrozen specimens are kept in their recovery state until transport to the laboratory.
Impressions
In contrast to the variety of procedures applicable to the recovery of actual fiber artifacts, the treatment of impressions is more or less uniform. Impressions may be preserved on living floors, in graves or fire features or, more rarely, in trash or midden areas. They are also common on certain types of pottery, as well as on the asphalt or plant-resin linings of baskets. These linings, which rendered the containers watertight, frequently outlive the vessels and preserve a strikingly detailed negative imprint. Plaited or twined fiber artifacts used in the construction of-house walls or roofs may leave clear marks on the mud, clay, or daub packing. Although virtually all the varieties of impressions noted above involve no more than careful excavation, handling, and packaging for successful recovery, the yield of impressions from archaeological sites is pitifully small. The principal problem lies in recognition, since most impressions appear even less artifact-like than incinerated or carbonized remains. Surprisingly, even imprints on pottery and basket-linings are frequently ignored or, at best, misidentified.
The recovery of impressions requires prompt perception of traces and slow, careful excavation with delicate instruments. Virtually any pattern, no matter how symmetrical or asymmetrical, which appears on an excavation floor, firepit lining, chunk of burned daub, potsherd, or other surface should be treated as a potential imprint. Specimens from dry caves and rockshelters may be so encrusted with sediment or animal excrement as to be unrecognizable. Consequently, items of this kind should be taken to the laboratory for careful examination.
Before their removal is attempted, impressions should be exposed in much the same manner as charred or incinerated specimens, and then drawn and photographed in situ. If the impressions are on objects, such as ceramic sherds, daub, or pitch linings, and if these objects are firm, they should be removed and wrapped as carefully as their condition requires. If the impressions are on floors or objects too frail to withstand disturbance, extensive stabilization procedures may be necessary. Before any stabilization or removal is attempted, however, the impressions should be photographed and also analyzed as completely as possible in case the measures to preserve them are unsuccessful.
The disintegration of fiber artifacts on a fine clay or silt floor may leave a negative pattern with a large number of construction attributes preserved under the overlying matrix. The delicate task of separating the matrix from the negative impression is facilitated by applying water to the structural parts of the pattern. Ideally, the fill can then be peeled out with needles or probes, exposing the pattern.
The success of the separation depends on the texture and composition of the floor or the object bearing the impression, as well as on the makeup and condition of the overlying matrix. Sandy fill is relatively easy to separate from a fired clay floor, whereas other combinations of earth are virtually inseparable. Compressed air or water picks can sometimes be substituted for the needle/probe method described above. The choice of technique must be dictated by local conditions.
After exposure, the impression should be analyzed in precisely the same manner as a preserved specimen of that class of fiber artifact. All pertinent measurements should be taken and the cleared impression should be re-photographed if necessary. The object or matrix containing the impression should then be cleaned manually or with an airbrush as much as possible and the surface consolidated with a suitable agent. At this juncture, a cast or positive impression should be taken. Ordinary modeling clay, liquid latex or its equivalent, or even plaster of Paris can yield satisfactory results. The selection of a casting medium is usually dictated by local circumstance and preference or experience. Consolidating the surface of the impression before casting minimizes the adsorption of extraneous materials by the casting medium and facilitates separation of the cast from the impression. Naturally, all the caveats normally associated with casting apply to contexts involving fiber artifacts, and patience coupled with a willingness to modify techniques is required to achieve success.
Upon completion of the casting, the negative impression can be removed en bloc and suitably packaged for transport to the laboratory. Should the impression disintegrate during removal or transportation, the field procedures will ensure a documentary record.
World History
