Freshwater ecosystems are positioned at low levels in the landscape and receive large inputs of diverse plant-based detritus, a major source of energy for consumers in aquatic ecosystems. We conducted Þeld experiments in Urbana, IL to determine the independent and combined effects of leaves of common tree species including thenorthern redoak (Quercus rubraL.), sugarmaple (Acer saccharumMarshall...

With global warming, an advance in spring leaf phenology has been reported worldwide. However, it is difficult to forecast phenology for a given species, due to a lack of knowledge about chilling requirements. We quantified chilling and heat requirements for leaf unfolding in two European tree species and investigated their relative contributions to phenological variations between and within po...

this experiment was carried out to investigate the effect of adaptation period to oak leave's tannin on rumen ph and ammonia, rumen microbial population, gas production and dry matter true digestibility (ivtdmd) in alamout goat’s rumen (with no previous history of oak leaf consumption) compared with markhoz goat (with previous history of oak leaf consumption). the goats were fed either oak...

one of the most visible aspects of a forest stand structure is the spatial patterns of trees. competition affects on forest structure and its understanding is important, when the purpose of forest management is to imitate the dynamic of natural ecosystems. for this purpose, an unmanaged intact forest was selected with 26 hectares area. all chestnut leaf oak (quercus castaneifolia) trees with a ...

Freshwater ecosystems are positioned at low levels in the landscape and receive large inputs of diverse plant-based detritus, a major source of energy for consumers in aquatic ecosystems. We conducted field experiments in Urbana, IL to determine the independent and combined effects of leaves of common tree species including the northern red oak (Quercus rubra L.), sugar maple (Acer saccharum M...

About 95% of swamp tupelo (Nyssa sylvatica var. biflora (Walt.) Sarg.) and sweetgum (Liquidambar styraciflua L.) seedlings survived continuous root flooding for more than two years, whereas none of the swamp chestnut oak (Quercus michauxii Nutt.) and cherrybark oak (Q. falcata var. pagodifolia Ell.) seedlings survived one year of flooding. Death of oak seedlings occurred in phases associated wi...

A newly recognized, late-season leaf disease of Quercus macrocarpa (bur oak) has become increasingly severe across Iowa and in neighboring states since the 1990s. Vein necrosis and leaf death may occur over the whole crown or only on the lower branches. Symptoms typically intensify year-to-year in individual trees, and there appears to be substantial variation in susceptibility. Distinctive con...

Although the effect of litter mixture on decomposition has been well documented, few studies have examined the relationships between richness and relative abundance of leaf species in litter mixture and changes in universal fungal communities during the decomposition process in temperate forests. In this study, we used the litterbag method and included three leaf litter species, i.e., aspen (Po...

Introduced plants tend to experience less herbivory than natives, although herbivore loads vary widely. Herbivores may switch hosts onto an introduced plant for at least two reasons. They may recognize the novel plant as a potential host based on similarity of the plant's traits to the traits of one of its native hosts, a similarity that may or may not exhibit phylogenetic signal. Alternatively...

General models of plant vascular architecture, based on scaling of pipe diameters to remove the length dependence of hydraulic resistance within the xylem, have attracted strong interest. However, these models have neglected to consider the leaf, an important hydraulic component; they assume all leaves to have similar hydraulic properties, including similar pipe diameters in the petiole. We exa...