Treesearch

Until it was discovered in Boulder, Colorado in 2013, the invaded range of the emerald ash borer, Agrilus planipennis, in the Western Hemisphere was entirely limited to natural and urban forests of eastern North America. Subsequently, this species has expanded its range through much of the Colorado Front Range region, utilizing non-native ash, Fraxinus spp. These host trees are widely planted there in urban settings but natural forests containing ash are lacking in the region. Here we use survey data to quantify emerald ash borer regional spread across the Colorado Front Range as well as...

Propagule pressure is one of the key drivers of establishment success of non-native species, including insects. However, border interception data, which have the potential to act as a proxy for true arrival rates (i.e., propagule pressure) of insects into a country, are seldom used to predict invasions. This can be due to the limited amount of interception data in some countries, difficulties accessing such data, and when these data are available, difficulties in addressing biases caused by variation in interception probability for different taxa due to policy changes, and operational...

A new subgenus and four new species of Adelges (Hemiptera: Adelgidae) are described from Bhutan. To support their taxonomic placement, we provide a phylogeny of Adelgidae reconstructed using mitochondrial and nuclear DNA sequence data. Cassiadelges subgen. nov is distinguished by the combination of feeding on Larix secondary hosts, having tergites of the head and pronotum fused into a cephaloprothoracic shield, and having only acuminate setae on the terminal abdominal segments. Adelges (Cassiadelges) coccipus sp. nov. feeds on Larix griffithii. This remarkable species is the only known...

This document contains abstracts and papers of the oral and poster presentations offered at the 31st annual U.S. Department of Agriculture interagency research forum on invasives species held in Annapolis, MD, in January 2023. The forum, sponsored by the Forest Service, Animal and Plant Health Inspection Service, National Institute of Food and Agriculture, and Agricultural Research Service, illustrates the depth and breadth of studies supported by the agencies and their cooperators.

Root nodule symbiosis is traditionally recognized in the Fabales, Fagales, Cucurbitales, and Rosales orders within the Rosid I clade of angiosperms. However, ambiguous root nodule formation has been reported in Zygophyllaceae and Roystonea regia (Arecaceae), although a detailed analysis has yet to be conducted. We aimed to perform morphological analyses of root structures in these plants and utilize metagenomic techniques to identify and characterize the bacterial populations within the nodule-like structures. We collected root samples of Tribulus terrestris (Zygophyllaceae) and Roystonea...

Spodoptera litura Fabricius (Lepidoptera: Noctuidae) is a major agricultural pest, primarily in Asia and Oceania. Chemical odor-based trapping is a major method used to control S. litura, and thus understanding the antennal sensilla of S. litura is critical for improving the efficacy of attractants used in pest control. In the present study, the types of S. litura antennal sensilla were examined by low-voltage field emission scanning electron microscopy, and morphological descriptions were provided. A total of eight types and two subtypes of the antennal sensilla were identified, namely...

1. Urban natural area forests provide cities with crucial ecosystem services, including carbon storage and sequestration. Although previous work from a single city has suggested that urban natural area forests may be carbon-rich and dominated by native species, it is unclear if that pattern is widespread. Indeed, little is known about the species composition and carbon storage in these green spaces, or how urban natural area forests compared with similar rural forests. 2. Here, we use data collected by the Forests in Cities network to quantify carbon stored in urban natural area forests...

Soil carbon is an important component of the terrestrial carbon cycle and could be augmented through improved soil management to mitigate climate change. However, data gaps for numerous regions and a lack of understanding of the heterogeneity of biogeochemical processes across diverse soil landscapes hinder the development of large-scale representations of soil organic matter (SOM) dynamics. In this Perspective, we outline how understanding soil formation processes and complexity at the landscape scale can inform predictions of soil organic matter (SOM) cycling and soil carbon sequestration...

Eastern spruce-fir forests, characterized by red spruce (Picea rubens) and balsam fir (Abies balsamea), cover millions of acres in the northeastern United States and southeastern Canada. Many spruce-fir forests are managed for wood production and wildlife habitat. To best manage these forests for the resources they provide, it is important to determine the stocking, that is, the size and number of trees in a given stand. The stocking provides different levels of growth and canopy closure, which informs managers when and how to thin the stand. Researchers from the U.S. Department of...

Long-term planning is crucial in forestry, where decisions often need to be made decades in advance. However, anticipating the future is difficult because changes are happening faster and becoming more complex. In addition, many changes that could affect forestry— for example, social trends, technological advances, and economic disruptions—come from fields outside of forestry.