BACKGROUND AND AIMS In some dicotyledonous leaves and leaflets, the secondary veins run more-or-less straight to the margins and have well-defined lengths. For a given half-lamina of length L, an equation, previously proposed, relates the lengths of these veins, p, to the distances, l, between the leaf tip and their insertions on the midrib: p = B2(x+y)l(x)(L - l)(y)/L(x+y-1), where B, x and y ...

Natural hybridization between introduced species and their native congeners occurs frequently and can create serious conservation concerns. Ulmus pumila (Siberian elm) is an introduced Asian elm species that has naturalized in the United States and is now considered invasive in 41 states. Red elm (U. rubra), a native to the eastern United States, often occurs in sympatry with Siberian elm, and ...

The reason for this study was to compare the morphology of mites from three Japanese samples with topotypes Nalepa collection, in order correctly identify them. With purpose eriophyoid specimens were recovered five vials mite collection Natural History Museum Vienna. We identified seven species and a new combination is established one them - Aceria thomasi Aculops thymi, two labeled Thymus serp...

The aphid genus Tinocallis Matsumura, 1919 (Hemiptera: Aphididae: Calaphidinae) in central and northern Europe is reviewed; it includes four species. The first records of the Asian elm aphid Tinocallis takachihoensis Higuchi, 1972 are reported from the Czech Republic, Denmark, and Poland. The record in Denmark is the first in Scandinavia. Alate viviparous females and nymphs of T. takachihoensis...

Abstract Laboratory feeding and fecundity bioassays, field defoliation surveys were conducted on 73 Ulmus eight Zelkova taxa to determine their relative susceptibility, preference, suitability for the adult Japanese beetle (Popillia japonica Newman). alata Michx., U. crassifolia Nutt., davidiana Planch., elliptica K. Koch, , glabra Hudson, laevis Pall., microcarpa, L.K. Fu, multinervis (syn. ca...

In a multiple-choice test, the preference of egg-laying Polygonia c-album (comma butterfly) females was studied for oviposition on plants bearing surrogate leaves treated with crude methanol extracts obtained from leaves of seven host-plant species: Humulus lupulus, Urtica dioica, Ulmus glabra, Salix caprea, Ribes nigrum, Corylus avellana, and Betula pubescens. The ranking order of surrogate le...

Context: Celtis australis L. (Ulmaceae) is a deciduous tree distributed to mountainous and sub-mountainous Himalaya. This plant has been used as traditional medicine in bone fracture, pimples, contusions, sprains and joint pains in India. Objectives: This is the first evaluation of C. australis extracts (bark and fruits) and fatty acids (fruits) for acute toxicity, analgesic, and anti-inflammat...