Early Detection of Brown Rot Decay in Douglas-Fir and Southern Yellow Pine by Infrared Spectrophotometry

David G. Gibson, Robert L. Krahmer, Rodney C. DeGroot


Samples of Douglas-fir heartwood and southern yellow pine sapwood were incubated with several brown rot rungi and examined for decomposition as shown by weight losses (to 10%). Warm-water extracts from the samples were analyzed by infrared spectrophotometry. An absorption peak at 1,720 cm-1 appeared in infrared spectra of decayed specimens but was not present in nondecayed specimens. As weight loss increased, the ratio of the absorbance at 1,720 cm-1 to the absorbance at 1,630 cm-1 increased. The ratio correlated with days of incubation and modulus of rupture.


Douglas-fir;southern yellow pine;brown not;infrared analysis;strength loss

Full Text:



  • There are currently no refbacks.