We studied the evolution of leaf size, sapling canopy allometry, and related traits in 17 Acer species growing in the understory of temperate deciduous forests, using parsimony methods, randomization tests, and independent contrasts calculated on a phylogeny inferred from nuclear ribosomal internal transcribed spacer (ITS) sequences. Bivariate correlations and multivariate analyses indicated tw...

The traditional explanation for the exceptional diversity of herbivorous insects emphasizes host shift as the major driver of speciation. However, phylogenetic studies have often demonstrated widespread host plant conservatism by insect herbivores, calling into question the prevalence of speciation by host shift to distantly related plants. A limitation of previous phylogenetic studies is that ...

Abstract A reproductive population of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), an adventive insect from Asia, was discovered in 2003 urban landscape Ontario, Canada. This polyphagous which attacks maples, Acer spp. (Sapindaceae), had potential to seriously and permanently alter composition structure forests eastern North America. The Canadi...

Watershed budget studies at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, have demonstrated high calcium depletion of soil during the 20th century due, in part, to acid deposition. Over the past 25 years, tree growth (especially for sugar maple) has declined on the experimental watersheds at the HBEF. In October 1999, 0.85 Mg Ca/ha was added to Watershed 1 (W1) at the HBEF i...

The objective of the study carried out at Botanical Garden Southern Federal University (Rostov-on-Don, Russia) was to assess seasonal changes in photosynthetic pigments contents leaves maples Acer campestre L., A. negundo and saccharinum L. Leaves samples were collected from selected maple trees once a week. chlorophylls carotenoids determined spectrophotometrically expressed per leaf area (mg/...