Betula papyrifera

Paper birch, Betula papyrifera leaf various distances from nickel smelter June vs. August... 

Johnson, D., and Hale, B. (2004). White birch (Betula papyrifera Marshall) foliar litter decomposition in relation to trace metal atmospheric inputs at metal-contaminated and uncontaminated sites near Sudbury, Ontario and Rouyn-Noranda, Quebec, Canada. Environ. Poll. 127, 65-72. 

TABLE 4-5. Distribution of Lignin in Birch (White Birch, Betula papyrifera) Xylem ... 

Table 4 4 2 shows the experimental data for Br-Ka X-ray counts (I), UV absorbance (A) and the distribution of lignin for different morphological regions of white birch (Betula papyrifera) wood Because of the limited resolution of UV microscopy, the UV absorbance of the S, S3 layers and the middle lamella between cell corners (ML) cannot be measured Instead, the guaiacyl/syringyl ratios are assumed to be the same as in the S2 layer and the cell corner middle lamella (CC), respectively... 

For white birch Betula papyrifera), the results obtained by the bromination-EDXA combined with UV technique (Saka et al. 1988, Saka and Goring 1988) confirm, in general, the previous data obtained by UV microscopy alone (Fergus and Goring 1970a,b). This agreement indicates that any errors caused by specimen degradation in the electron beam were small (Mary et al. 1986). However, some discrepancies are found for the middle lamella and the ray parenchyma. 

Birch (Betula papyrifera) wood chips used in this work were obtained from Scierie John Lewis, a woodmill in the province of Quebec, Canada. The sample was composed of 53.5 % of sap wood and 46.5 % of inner and outer bark. The moisture content was 8.5 % as determined by placing a known quantity of sample in an oven at 102 3 C until a constant weight was reached. The elemental composition of the sample was 51.3 % C, 6.2 % H, 0,7 % N and 41.8 % O (by difference). Its ash content was 2,0 %,... 

Richardson, A. D., Berlyn, G. P. 2002. Spectral reflectance and photosynthetic properties of Betula papyrifera (Betulaceae) leaves along an elevational gradient on Mt. Mansfield, Vermont, USA. Am. J. Bot. 89 88-94. 

Most antifeedants are not as active as the available pesticides, so that they would have to be used at higher levels. They would work best if they were systemic to protect the growing tip of the plant. The supply from natural sources might not be large enough for crop use in many cases. The antifeedant derived from betulin from the bark of birch trees (Betula papyrifera,) shown in 11.25 is potentially available in large supply.140... 

Table I. Lignin and Wood Sugars in Sound and Decayed Betula papyrifera and...

Rouyn-Noranda and for nine other tree individuals from three different species (Abies balsamea (L.) Mill, Acer saccharum Marsh and Betula papyrifera Marsh) at Saint-Hippolyte (about 60 km north of Montreal, Canada) (unpublished data). 

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