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Aim: Species distribution models typically project climatically suitable habitat for trees in eastern North America to shift hundreds of kilometres this century. We simulated potential migration, accounting for various traits that affect species' ability to track climatically suitable habitat. Location: Eastern Canada, covering ~3.7 million km2. Methods: We simulated migration‐constrained range shifts through 2100 using a hybrid approach combining projections of climatically suitable habitat based on two Representative Concentration Pathways (RCP4.5, RCP8.5) for three time periods and two species distribution modelling approaches with process‐based models parameterized using data related to dispersal ability and generation time. We developed a unique "migration kernel" that uses seed dispersal traits and observed migration velocities to obtain kernel shape and dispersal probabilities for each tree species. We then calculated lags between the migration‐constrained range limits obtained through simulations and limits of climatically suitable habitat. Results: All species demonstrated northward range shifts at the leading edge of their simulated distribution through 2100, but the magnitude and rate of that shift varied by species and time period. Climatically suitable habitat limits were found to be north of simulated distribution limits across both RCPs, with lags increasing through time. On average, simulated distribution that remained within climatically suitable habitat declined more under RCP8.5 than RCP4.5, with large areas of the rear edge of the simulated distribution becoming partially or completely climatically unsuitable for many species. Main conclusions: Climatically suitable habitat limits projected for 2100 far exceeded migration‐constrained range limits for all 10 tree species, particularly for temperate species. This study underlines the limited extent to which tree species will track climate change via natural migration. Integrating observed migration velocities, seed dispersal and generation time with SDM outputs allows for more realistic evaluations of tree migration ability under climate change and may help orient forest conservation and restoration efforts. [ABSTRACT FROM AUTHOR]

This study presents spatial models (i.e., thin-plate spatially continuous spline surfaces) of adjusted precipitation for Canada at daily, pentad (5 day), and monthly time scales from 1900 to 2015. The input data include manual observations from 3346 stations that were adjusted previously to correct for snow water equivalent (SWE) conversion and various gauge-related issues. In addition to the 42 331 models for daily total precipitation and 1392 monthly total precipitation models, 8395 pentad models were developed for the first time, depicting mean precipitation for 73 pentads annually. For much of Canada, mapped precipitation values from this study were higher than those from the corresponding unadjusted models (i.e., models fitted to the unadjusted data), reflecting predominantly the effects of the adjustments to the input data. Error estimates compared favorably to the corresponding unadjusted models. For example, root generalized cross-validation (GCV) estimate (a measure of predictive error) at the daily time scale was 3.6 mm on average for the 1960–2003 period as compared with 3.7 mm for the unadjusted models over the same period. There was a dry bias in the predictions relative to recorded values of between 1% and 6.7% of the average precipitations amounts for all time scales. Mean absolute predictive errors of the daily, pentad, and monthly models were 2.5 mm (52.7%), 0.9 mm (37.4%), and 11.2 mm (19.3%), respectively. In general, the model skill was closely tied to the density of the station network. The current adjusted models are available in grid form at ~2–10-km resolutions. [ABSTRACT FROM AUTHOR]

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The application of trivariate thin-plate smoothing splines to the interpolation of daily weather data is investigated. The method was used to develop spatial models of daily minimum and maximum temperature and daily precipitation for all of Canada, at a spatial resolution of 300 arc s of latitude and longitude, for the period 1961–2003. Each daily model was optimized automatically by minimizing the generalized cross validation. The fitted trivariate splines incorporated a spatially varying dependence on ground elevation and were able to adapt automatically to the large variation in station density over Canada. Extensive quality control measures were performed on the source data. Error estimates for the fitted surfaces based on withheld data across southern Canada were comparable to, or smaller than, errors obtained by daily interpolation studies elsewhere with denser data networks. Mean absolute errors in daily maximum and minimum temperature averaged over all years were 1.1° and 1.6°C, respectively. Daily temperature extremes were also well matched. Daily precipitation is challenging because of short correlation length scales, the preponderance of zeros, and significant error associated with measurement of snow. A two-stage approach was adopted in which precipitation occurrence was estimated and then used in conjunction with a surface of positive precipitation values. Daily precipitation occurrence was correctly predicted 83% of the time. Withheld errors in daily precipitation were small, with mean absolute errors of 2.9 mm, although these were relatively large in percentage terms. However, mean percent absolute errors in seasonal and annual precipitation totals were 14% and 9%, respectively, and seasonal precipitation upper 95th percentiles were attenuated on average by 8%. Precipitation and daily maximum temperatures were most accurately interpolated in the autumn, consistent with the large well-organized synoptic systems that prevail in this season. Daily minimum temperatures were most accurately interpolated in summer. The withheld data tests indicate that the models can be used with confidence across southern Canada in applications that depend on daily temperature and accumulated seasonal and annual precipitation. They should be used with care in applications that depend critically on daily precipitation extremes. [ABSTRACT FROM AUTHOR]

The Emerald Ash Borer (EAB), Agrilus plaipennis (Coleoptera: Buprestidae) was introduced to North America more than two decades ago and has spread despite management efforts in both the United States and Canada. The insect kills most species of ash tree (Fraxinus sp.) and its management imposes costs to plant health protection agencies, forest industry, private landowners and municipalities. The United States Department of Agriculture – Animal and Plant Health Inspection Service (USDA-APHIS) has deemed existing regulation efforts in the United States to be ineffective and has removed federal regulations designed to limit the spread of EAB. The Canadian Food Inspection Agency (CFIA) is also trying to determine if continued regulation of EAB in Canada is worthwhile. Here we show that the benefits of slowing the spread of EAB via regulation are likely greater than the costs of implementing regulation if it is minimally effective (i.e. more than 25% effective at preventing anthropogenic spread). To evaluate the economic efficiency of existing Canadian EAB regulations, we examined trade-offs between the monetary benefits of regulation and the costs of regulation. Specifically, we simulated the spread of EAB under various levels of regulation effectiveness and estimated the timing of EAB arrival and associated ash mortality in urban and rural settings. Delaying ash mortality via regulation also delays management costs, a benefit to ash tree owners/users. Our findings suggest that an economic justification to continue regulating the insect exists based on monetary costs alone. The net present value of regulation (benefits less costs) is estimated to range between $23 million to $240 million, depending on the level of regulation effectiveness. Additional environmental and social benefits not addressed here would likely increase the value of EAB regulation but appear unneeded to justify such efforts on allocative efficiency grounds. [Display omitted] • Emerald Ash Borer causes significant tree mortality and economic costs in urban and rural settings. • Regulation delays damages and is economically efficient under a wide range of assumptions. • EAB's distribution seems likely to extend to the Pacific coast by 2035, regardless of regulation. • Cost of regulation to slow EAB spread is minimal compared to possible benefits of delaying insect. [ABSTRACT FROM AUTHOR]

Herein, we assessed the utility of the Canadian Study of Health and Aging Clinical Frailty Scale (CSHA-CFS) to predict burn-specific outcomes. We hypothesized that frail patients are at greater risk for burn-related complications and require increased healthcare support at discharge. Patients 50 years and older admitted to our institution for burn injuries between July 2009 and June 2019 were included. Demographics, comorbidities, pre-injury functional status, injury and hospitalization information, complications (graft loss, acute respiratory failure, and acute kidney disease [AKI]), mortality, and discharge disposition were collected. Multivariate analyses were performed to assess the association between admission frailty scored using the CSHA-CFS and outcomes. P < .05 was considered significant. Eight-hundred fifty-one patients were included, 697 were not frail and 154 were frail. Controlling for Baux scores, sex, race, mechanism of injury, 2nd and 3rd degree burn surface, and inhalation injury, frailty was associated with acute respiratory failure (OR = 2.599 [1.460-4.628], P = .001) and with mortality (OR = 6.080 [2.316-15.958]; P < .001). Frailty was also associated with discharge to skilled nursing facility, rehabilitation, or long-term acute care facilities (OR = 3.135 [1.784-5.508], P < .001), and to hospice (OR = 8.694 [1.646-45.938], P = .011) when compared to home without healthcare services. Frailty is associated with increased risk of acute respiratory failure, mortality, and requiring increased healthcare support post-discharge. Our data suggest that frailty can be used as a tool to predict morbidity and mortality and for goals of care discussions for the burn patient., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Burn Association. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)