Figure 3.

A to F, Raman images (30 × 30 μm) of poplar tension wood integrating over defined wavenumber areas. A, Intensity of the aromatic lignin band (1,550–1,640 cm⁻¹; marked line is analyzed in detail in Fig. 4). B, Intensity from 1,550 to 1,640 cm⁻¹ with a changed intensity scaling to show lignin distribution within the G-layer. C, Intensity from 3,050 to 3,640 cm⁻¹ (water). D, CC and C–O str. (carbohydrate region) from 1,026 to 1,195 cm⁻¹. E, C–H str. of cellulose (2,810–2,936 cm⁻¹). F, Intensity of the 1,097 cm⁻¹ band (1,090–1,105 cm⁻¹).