Weedy and invasive plants threaten our food supply, native biodiversity, and the structure and function of ecosystems. The number and impact of these damaging plants are expected to continue to grow with ongoing global change. Some of the most common policy tools to help mitigate this threat are regulatory weed lists, which limit the importation and movement of listed plant species, but there has never been a comprehensive analysis of plants regulated in the United States. We analyzed US state regulatory lists (e.g., noxious, invasive, prohibited) to evaluate their composition, patterns of listing, congruities with weed distributions, and limitations. In total, 46 states maintain regulatory weed lists that include 3210 total listings of 1249 unique species; 48% of them are introduced, 40% are native, and 12% are not yet found in the United States. Overall, the listed species are not a good reflection of the weeds in each state, and listing appears largely reactive, regulating species after they become widespread. We highlight patterns and incongruities among lists and discuss their implications, especially the large number of regulated species native to the United States.

Aquatic ecosystem enrichment can lead to distinct and irreversible changes to undesirable states. Understanding changes in active microbial community function and composition following organic matter loading in enriched ecosystems can help identify biomarkers of such state changes. In a field experiment, we enriched replicate aquatic ecosystems in the pitchers of the northern pitcher plant, Sarracenia purpurea. Shotgun metaproteomics using a custom metagenomic database identified proteins, molecular pathways, and contributing microbial taxa that differentiated control ecosystems from those that were enriched. The number of microbial taxa contributing to protein expression was comparable between treatments; however, taxonomic evenness was higher in controls. Functionally active bacterial composition differed significantly among treatments and was more divergent in control pitchers than in enriched pitchers. Aerobic and facultative anaerobic bacteria contributed most to identified proteins in control and enriched ecosystems, respectively. The molecular pathways and contributing taxa in enriched pitcher ecosystems were similar to those found in larger enriched aquatic ecosystems and are consistent with microbial processes occurring at the base of detrital food webs. Detectable differences between protein profiles of enriched and control ecosystems suggest that a time series of environmental proteomics data may identify protein biomarkers of impending state changes to enriched states.

The recent emergence of the fungus Cryptostroma corticale in Seattle, Washington, USA is concerning because of its invasive status in Europe, where it causes sooty bark disease of maples (SBD), killing both forest and urban trees. Additionally, the fruiting bodies (stromata) of C. corticale produce allergenic spores that can impact human health. Therefore, its presence in Washington has the potential to impact the state's populace and trees, including the native bigleaf maple, Acer macrophyllum. To better determine the distribution of C. corticale in western Washington, A. macrophyllum was surveyed on 50 Washington State Park properties. Bark samples were collected from trees with fruiting bodies resembling those of C. corticale and cores were removed from mature asymptomatic trees. The presence of C. corticale was confirmed using nested PCR. Acer macrophyllum with fruiting bodies of C. corticale were well distributed throughout western Washington, with an 89% detection rate at surveyed Park properties containing A. macrophyllum. Core samples indicated that latent infections appeared well distributed and common throughout western Washington on mature A. macrophyllum, with a 91% detection rate at surveyed Park properties containing A. macrophyllum and a 68% detection rate on cored trees. Signs of SBD and evidence of latent infections of C. corticale were widespread at surveyed properties. However, signs of SBD were rare on individual trees and the overall condition of A. macrophyllum was considered vigorous at the majority of Park properties. Awareness of C. corticale, SBD, and their likelihood to be present on a property containing A. macrophyllum in western Washington should help inform management actions and demonstrate the need for future research.

The invasive tree of heaven, Ailanthus altissima (Miller) Swingle, was first confirmed dying from Verticillium wilt (caused by both Verticillium nonalfalfae Inderb. et al. formerly V. albo-atrum Re...