Yellow birch

B J.W. Cole, M.D. Bentley, Y. Hua, L. Bu, Triterpenoid constituents in the outer bark of Betula alleghaniensis (yellow birch), Journal of Wood Chemistry and Technology, 11, 209 223 (1991). 

A comprehensive study of the properties of acetylated wood was undertaken by the Forest Products Laboratory in Madison, Wisconsin, and included an investigation of the mechanical properties of acetylated wood (Tarkow etal., 1946). The property changes were not significant, but there was some variation between species. For example, Sitka spruce and basswood exhibited increases in strength and MOE upon acetylation to about 20 % WPG, whereas yellow birch showed a decrease in these properties at 16 % WPG. 

Patterns of polyphenol accumulation In leaves vary among the few temperate forest species which have been studied. Feeny s (42) classic study on oak leaves (Quercus robur) shows leaf tannin levels rising slowly until August, and then Increasing sharply. In the cases of sugar maple (Acer saccharum) and yellow birch (Betula lutea) (44), respectively. 

Figure 1. Leaf-to-leaf variation in four traits along a single branch of sugar maple (left) and yellow birch (right) on 6/23/81. Horizontal axis is mean of each measure for that branch hatched area is one standard deviation. Each black bar represents the actual value for one leaf, plotted as deviation from the mean. Branch terminus is to right yellow birch leaves D and E are at least 10 days younger than the others.

Over a period of a month, tanning coefficients increased dramatically, and seasonal (2 month) increases in hydrolyzable tannins were observed in trees undergoing defoliation. Preliminary studies of yellow birch and sugar maple suggest that day-to-day responses in phenolic production may be generated by damage to leaves (39). 

Figure 4. Binding of a protein (hemoglobin) to several tannin extracts (tannic acid, sugar maple tannins, yellow birch tannins, quebracho tannins see 29) at various pH values. Ranges of microbial chitinase activity, NPV activity, and Bt toxicity are given. See text for discussion and references.

The average service life of acetylated yellow birch and cyanoethylated southern pine stakes in ground contact is shown in Table II (27). 

Figure 3. Temperature dependence of rate of wet-strength loss caused by dry heat in joints of yellow birch and Douglas-fir with acidic and nonacidic adhesives (48).

Table III. Permeability of Yellow Birch in Three Directions...

The wood adherends were clear, flat-grained, rotary-peeled yellow birch veneer with moisture content equilibrated at 27 °C and 30% relative humidity (RH). The pieces were 3.2 mm thick and 150 mm by 150 mm in area. 

Table I. Shear Strength Properties of Yellow Birch Panels Bonded with Glucose-Based Adhesives...

Table II. Effect of Urea/Carbohydrate Mole Ratio (0.125 1) on Adhesive Shear Strength of Yellow Birch Panels...

Phenol/carbohydrate/urea/formaldehyde resin with molar ratios of 1 1 0.125 2, 2.09 Pa-s viscosity, bonded between two parallel-laminated yellow birch veneers for 5 minutes. 

Fig. 8.1 Feeding preferences by free-ranging beavers Castor canadensis) for 3 species of northeastern deciduous trees and shrubs American beech (Fagus grandifolia), quaking aspen Populus tremuloides), striped maple (Acer pensylvanicum), witch hazel (Hamamelis virginiana), witch hobble (Viburnum lantanoides) and yellow birch (Betula alleghaniensis). The experiment was run over 10 days. Each morning the number of remaining sticks was counted. Only one of 10 beech sticks was taken after 10 days, while, at the other extreme, no sticks of aspen and striped maple remained after 4 and 5 days, respectively...

Mushrooms partly consumed by animals question of toxins and avoidance Leaves partly eaten by insects Yellow birch odor Browsed fern... 

Figure 10. Light micrograph of the three types of pore patterns of growth increments in hardwoods as seen in cross section. Key A, ring-porous (red oak) B, semi-ring-porous (aspen) and C, diffuse-porous (yellow birch). (Reproduced with permission from Ref. 40. Copyright 1982, Technical Association of the Pulp and Paper Industry Press.)...

Betula lutea Michx. F. (Yellow Birch) Sapwood 55 67 37 58 146 215 1047... 

Hemingway (1969) showed that in the high temperature drying of yellow birch veneer, fatty acids and other extractives influenced the wetting of veneers in a complex manner and showed that the observed effects were due to acetone extractives. 

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