Quaking aspen tree

The quaking aspen tree (Populus tremuloides) is a common tree in North America that is used for its timber. The wood-rotting pathogen Phellinus tre-mulae causes significant economic losses of this tree. Although the sesqui-terpenoid metabolites such as tremulenolide A (5.89) have a carbon skeleton that is isomeric with the lactaranes, some doubts have been expressed on its biosynthetic origin from farnesyl diphosphate. 

Female flowers of dioecious trees are better defended than males. RuflFed grouse, Bonasa umbellus, prefer male flowers of quaking aspen, Populus tremuloides, in winter, and leaves of male specimens in summer (Svoboda and Gullion 1972). Ruffed grouse also feed more on male trees of balsam poplar (Bryant etal, 1991). 

FIGURE 11.24 Leaching (a) Standard pieces of different trees leach out different amounts of phenolics and other compounds. During 24 hours, red maple and witch hazel (left) stain water a darker brown than willow and quaking aspen (right), (b) and (c) Beavers leave pieces of branches in the water for 1-3 days with some or all bark intact before eating the bark. This presumably leaches out water-soluble plant secondary compounds. 

In addition to the unique and quite dramatic differences in feeding/survival of larvae of the P. glaucus complex and their hybrids (2 0) (Table III), tulip tree and quaking aspen represent phytochemically intriguing foodplants for several other North... 

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...

Fig. 8.3 A mixed feeding experiment with free-ranging beavers, including six species of deciduous trees and shrubs, and two growth forms (adult and juvenile) of quaking aspen. The experiment was run for 5 days. Note the two extremes witch hazel vs. adult form of aspen...

The genus Populus includes hardwood trees commonly referred to as poplars, cottonwoods, and aspen, which are found throughout North America, Europe, and northern Asia. They are particularly dominant in the boreal forest and in the parkland zones of Canada and the American midwest. Widespread North American species include P. balsamifera (balsam poplar), with a range from Western Alaska to northern Quebec and Newfoundland, and P. tremuloides (trembling or quaking aspen), which is found from Alaska to Mexico. Both are prominent species of the boreal forest of Canada. P. trichocarpa (black cottonwood) is found along the Pacific coast from California to Alaska. The range of P. tremula (European aspen)... 

Eucalyptus wood Olive wood Oak bark Beech wood Birch wood Alder tree Quaking aspen Teak wood tree Black wattle tree Sisal tree trunk... 

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