Advances in in Situ Evaluation of Timber Structures
Kasal, Bohumil, and Ronald W. Anthony · 2004 paper
Progress in Structural Engineering and Materials 6, no. 2: 94-103.
https://doi.org/10.1002/pse.170
Internal decay routinely leaves no surface sign (p. 95). Vocabulary for the condition fields comes from here. General research, not an assessment of any piece in this stock.