Wattle & Daub: Craft, Conservation & Wiltshire Case Study
Contents 2 History
3 Craft
3.3 Panel Types
3.4 Staves
3.6 Daub
3.7 Decoration
4.1 Soils
4.1.1 Constituents
4.1.2 Plasticity
4.1.3 Strength
4.1.4 Field Testing
4.1.5 Selection
4.2 Dung
4.2.2 Lignin
4.2.3 Urine
4.2.4 Microbial Debris
4.2.5 The Role of Dung
4.3 Fibre
5.2.3 Maintenance
5.3 Repair
5.3.1 Partial Renewal
5.4 Replacement
5.4.1 Brick Infill
5.4.2 Renewal
6.3 Fieldwork
6.5 Evaluation
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4.2.4 Microbial DebrisThe microbial debris makes up the majority of the faeces. It
has been established that such organic matter helps bind soil aggregates, yet an
organic soil also has the undesirable property of being volumetrically unstable
and so may shrink in a manner similar to
clay.[70]
It is possible that the faecal microbial debris in daub is prevented from
decomposition by becoming biochemically-protected (chemical compounds that are
not subject to decomposition), silt- and clay-protected, or
microaggregate-protected (physically protected), although the function of the
latter is known to predominate. However, a soil may become saturated with
organic material due to limits of these protection mechanisms. Therefore, if too
much dung is added to a soil it is likely that a proportion of the organic
matter will be unprotected and may then decompose and damage the
daub.[71]
Protection mechanisms therefore assist a soil to stabilise added microbial
debris (i.e. to nullify the affects of organic matter) but do not represent a
benefit in their addition to a daub.
[70]
New Zealand Ministry of Agriculture and Forestry (2004).
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