Notes on North American Trees. III. Tilia. II

New Synonymy , New Species , and Taxonomic Notes of North American Pityophthorus ( Coleoptera : Scolytidae ) , Part Iii

— New synonymies and new data affecting North American Pityophthortis are proposed as follows: chalcoensis Hopkins { = herrerai Hopkins) and nigricans Blandford ( = chiapensis Bright). Neotypes are designated for the following species described by Eichhoff: concentralis, cribripennis, infans, puchellus, and tuberculatus. New species are: carinatus (Canada), cavatus (Manitoba, Saskatchewan), eut...

Speaker’s notes on Trees

Notes on Binary Dumbbell Trees

Dumbbell trees were introduced in [1]. A detailed description of non-binary dumbbell trees appears in Chapter 11 of [3]. These notes show how binary dumbbell trees can be obtained, and how they can be used to construct, in O(n log n) time, a spanner of bounded degree and weight proportional to O(log n) times the weight of a minimum spanning tree. The reader is assumed to be familiar with the sp...

Spread of North American wind-dispersed trees in future environments.

Despite ample research, understanding plant spread and predicting their ability to track projected climate changes remain a formidable challenge to be confronted. We modelled the spread of North American wind-dispersed trees in current and future (c. 2060) conditions, accounting for variation in 10 key dispersal, demographic and environmental factors affecting population spread. Predicted sprea...

Fine Root Architecture of Nine North American Trees

The fine roots of trees are concentrated on lateral branches that arise from perennial roots. They are important in the acquisition of water and essential nutrients, and at the ecosystem level, they make a significant contribution to biogeochemical cycling. Fine roots have often been studied according to arbitrary size classes, e.g., all roots less than 1 or 2 mm in diameter. Because of the siz...