Trembling aspen

Trembling aspen, Populus tremuloides, 22eRa Near uranium tailings plant vs. control site Leaves 42 DW vs. 11-15 DW 4... 

Ruffed grouse, B. umhellus, feed on staminate flower buds and extended catkins of trembling aspen, P. tremuloides. In winter these birds select specific trees or clones. Analysis for alkaloids, tannins, and other phenolics showed that feeding preferences were not related to the levels of tannin or total phenolics in... 

Figure 7.3. Trace metal concentration in water extracts from the bulk soil and the inner rhizosphere of trembling aspen Populus tremuloi des Minchx) at Rouyn-Noranda. (Modified from S6guin et al., 2004.)...

Figure 7.4. Time-of-flight secondary-ion mass spectroscopy (ToF-SIMS) image of the distribution of Fe on a cross section of a trembling aspen (Populus tremuloi desMmchx ) root embedded in clayey soil material. The Fe values are normalized to the total ion yield of the surface. The bar is 100 (im. (From Martin et al., 2004.)...

Among the species referred to in Table III, only trembling aspen has given almost quantitative jdelds of (4-0-methylglucurono)xylans, - whereas the relative amounts obtainable from American elm are conspicuously low. (4-0-Methylglucurono)xylans have been isolated from white birch and silver birch in yields close to, or exceeding, 30% of the wood. 

Trembling aspen Direct extraction with alkali 18 212... 

In hybrid poplar and trembling aspen, leaf damage by wounding or herbivory induces polyphenol oxidase activity (PPO EC 1.10.3.2). This enzyme can... 

HARUTA, M., PEDERSEN, J.A., CONSTABLE, C.P., Polyphenol oxidase and herbivore defense in trembling aspen Populus tremuloides)-. cDNA cloning, expression, and potential substrates. Physiol. Plant, 2001,112, 552-558. 

PETERS, D.J., CONSTABEL, C.P., Molecular analysis of herbivore-induced condensed tannin synthesis cloning and expression of dihydroflavonol reductase from trembling aspen (Populus tremuloides). Plant J., 2002,32, 701-712. 

LINDROTH, R.L., OSIER, T.L., BARNHILL, H.R.H., WOOD, S.A., Effects of genotype and nutrient availability on phytochemistry of trembling aspen (Populus... 

HARUTA, M., MAJOR, I.T., CHRISTOPHER, M.E., PATTON, J.J., CONSTABEL, C.P., A Kunitz trypsin inhibitor gene family from trembling aspen Populus tremuloides Michx.) cloning, functional expression, and induction by wounding and herbivory. Plant Molec. Biol, 2001,46, 347-359. 

The study area is situated near Rouyn-Noranda, about 600 km to the north-west of Montreal, Canada (48°14 N, 79°01 W). Three sites were sampled at a downwind distance of 0.5, 2 and 8 km from the Horne copper smelter. At each site, soil samples were collected under three trembling aspen Populus tremuloides Michx) of similar age (< 30 years old). The soils developed in postglacial lake sediments of silt texture to form Luvisols, according to the Canadian System of Soil Classification (Soil Classification Working Group, 1998). The extent of soil contamination received through the atmospheric deposition of metals represents the main difference between the three sites as other characteristics were kept constant (e.g. climate, parent material, slope, aspect, etc.). For a more detailed description of the sites, see Seguin et al. (2004). 

Trembling aspen wood (Populus tremuloides Michx.) was reduced to a powder in a Hurricane Pulverizer. Samples were prepared from extracted pulverized wood by ball-milling for 10 days in a rotating ceramic mill equipped with an air-conditioning unit which prevented the temperature of the contents of the mill from rising above ambient. Digestion of the samples with cellulase was done with a mixture of Schizophyllum commune and Trichoderma reesei culture filtrates at 30°C for 3 days. 

In the absence of fire in the Boreal and the Great Lakes-St. Lawrence Forest Regions, jack pine is often succeeded by the more tolerant black spmce, white spmce and balsam fir (Cayford et al, 1967). On productive sandy sites in Minnesota, it may be succeed by red pine, then white pine and mixed hardwoods in some cases succession is directly to hardwoods such as white birch and trembling aspen (Rudolf, 1965). In the Boundary Waters Canoe Area of northern Minnesota, succession may be to black spmce - feather moss forest types, or balsam fir - white birch - white spmce types (Cayford and McRae, 1983). 

---