From an analysis of the dyeing properties of Canadian golden rod samples collected over a period of five years only relatively small differences in colour depth and shade were found among the major parts of the different materials collected.
At present for dried Canadian golden rod standardised laboratory dyeing experiments were found to be the most relevant procedure to select and adjust a batch of raw materials as to set level of colour depth and shade.
UV-vis photometry without addition of Fe(II)-salt or determination of TPH could support identification of material which will exhibit large deviation from the standardisation based only on analytical determination of these parameters cannot be recommended.
Considerable variation in absorbance of the extracts in the wavelength interval from 350 to 700 nm was found TPH concentrations varied from 3.10 g L to 7.10 g L while CIELab coordinates of the laborato dyengs on wall not change to the same exten. This could be explaing with presence of otherb coloured enponens, and ther of the textile substrates.