Treesearch

Presence of the introduced genus Tamarix has been a perplexing problem for decades along rivers of the southwestern States. It is clearly an invasive species occurring along most perennial, ephemeral, and intermittent drainages of the Southwest including rivers, small streams, and normally dry washes. It seems to reach highest densities and form monocultures along waterways with altered flow regimes, but it can also invade unaltered streams and small springs, where it may become the dominant or exclusive woody species. Approximately 150 years after Tamarix was first introduced into the...

The “mesquite bosque” (Spanish for “forest” or “woodland”), one of the most unique and productive southwestern riparian habitat types, was once far more abundant than it is today. Twenty-five years ago, Stromberg (1993), with a focus on Arizona, provided an excellent review on the ecology, decline, existing threats, and potential for recovery of these mesquite forests. By 1993 the iconic mesquite bosque riparian habitat was in serious decline, due primarily to anthropogenic activities. Stromberg (1993) observed that previous attempts at habitat restoration were of limited success and...

Application of progeny test breeding values to forecast yield gains at rotation-age in genetically improved stands remains a very challenging yet crucial task for breeders of Douglas-fir and other long-rotation timber species such as western hemlock, white spruce, Norway spruce, and Scots pine. Evaluation of the economic returns on genetic improvement requires reliable estimates of yield gains at rotation age. Large-plot realized gain trials should provide more accurate estimates of yield gain than inferences from progeny tests, but are most dependable when they reach rotation age or at...

What challenges await woodworkers involved in the construction based sectors and what investments are being planned to improve their capabilities? For an industry perspective, the total value of private construction (residential and non-residential) put in place in the United States was more than $978 billion in 2019, down from more than $1,000 billion in 2018.

Further investigations of new, noninvasive electronic methods for early White-Nose Syndrome (WNS)-disease diagnosis, based on e-nose VOC-detection of the disease itself, have provided new chemical evidence of metabolic differences in WNS-susceptible bat species. Development of improved methods for pre-symptomatic detection of WNS in bats using the portable C-320 electronic-nose (e-nose) has required multi-phase efficacy studies of instrument capabilities to discriminate between major sources of volatile organic compounds (VOCs) derived from clinical samples. In this phase-2 study, we...

The leccinoid fungi are boletes and related sequestrate mushrooms (Boletaceae, Basidiomycota) that have traditionally been placed in Leccinum, Boletus, Leccinellum, and a handful of other less familiar genera. These mushrooms generally feature scabers or scaber-like dots on the surface of the stipe, and they are often fairly tall and slender when compared with other boletes. They are ectomycorrhizal fungi and appear to be fairly strictly associated with specific trees or groups of related trees. In the present study, we investigate the phylogenetic relationships among the leccinoid fungi...

Crown widths of woody plant species growing in urban areas are of considerable importance as an overall indicator of health and also serve as an important factor for assessing leaf area and associated ecosystem services, such as carbon sequestration, air pollution removal, air temperature cooling, and rainfall interception. Unfortunately, assessing crown widths in urban environments is often challenging and time consuming. To help reduce data collection costs and provide consistency over time,models to predict crown widths for urban-grown species were developed using data from 49 cities...

One of the most wide-ranging scientific treatments of riparian vegetation of the American Southwest (exclusive of New Mexico and southwestern Colorado) can be found in the 2007 book, The Ribbon of Green by Robert Webb, Stanley Leake, and Raymond Turner (Webb et al. hereafter). In The Ribbon of Green, the authors use sets of matched photographs to evaluate and interpret historical changes in riparian vegetation along southwestern streams that have taken place since the late 19th century. As stated in the book’s preface, the authors “concentrate on the question of long-term changes, addressin...

Established between 1996 and 2010, a site in Dorset was the largest newly-created mainly broadleaved woodland in England. It covered 202 ha (499 acres) and the planted tree species were mostly native, intermixed with small components of non-native species. Historically the site had been managed as farmland for centuries (predominantly grassland but also arable crops), divided by undisturbed hedgerow systems. The site came to attention in 2011 when the site manager reported dieback of alder and ash (Fraxinus excelsior) trees. In an area of around 1 ha, more than 100 ash trees were observed...

Curculio and Conotrachelus weevils (Coleoptera: Curculionidae) can render the majority of North American Quercus spp. acorn crops nonviable, thereby reducing food resources for wildlife and limiting opportunities for seedling establishment. Acorn predation by weevils at the individual tree level can be influenced by many factors, and research specifically investigating acorn predation by weevils in seasonally flooded bottomland oak forests is lacking. We placed cone emergence traps in a periodically flooded forest on the Sam D. Hamilton Noxubee National Wildlife Refuge near Brooksville,...