Effect of a severe cold spell on overwintering survival of an invasive forest insect pest

Data from a study of a servere cold event in February 2023 on the survival of hemlock woolly adelgid (Adelges tsugae Annand) from four populations in Canada. Cold temperatures can play a significant role in the range and impact of pest insects. Severe cold events can reduce the size of insect outbreaks or in some cases even cause outbreaks to end. Measuring the precise impact of cold events, however, can be difficult because estimates of insect mortality are often made at the end of the winter season. In late January, 2023 long-term climate models predicted a significant cold event to occur over eastern North America. We used this event to evaluate the immediate impact on hemlock woolly adelgid overwintering mortality at four sites on the northern edge of the insects invaded range in eastern North America. We observed complete mortality, partial mortality and no effect of the cold event that correlated with the location and strength of the cold event. Our data also showed lack of suppor..., Insects were collected from infested trees at 4 sites in 2 Canadian provinces immediately before and immeditely after a severe cold spell. The health and status of the insects (live/dead) was determined in a laboratory. The survival was then compared to observed temperature data extracted from Environment and Climate Change Canada weather stations. , , # Data from: Effect of a severe cold spell on overwintering survival of an invasive forest insect pest

## Description of the data and file structure

There are 6 files in total: 1 ReadMe file, 2 data files and 6 associated code files (See Code/Software section).

ReadMe.txt: This file.

coldspell.csv: Records of number of hemlock woolly adelgid living and dead on shoots of hemlock trees collected from 4 sites in Canada, before and after a severe cold spell.

Description of fields:
-[];numeric; The row number for each record.
-[province];text; either \"Ontario\" or \"Nova Scotia\"; the Canadian province where the site was located.
-[site]; text; either \"Annapolis Royal NS\", \"Mersey River NS\", \"Grafton ON\" or \"Wainfleet ON\"'; the sites where samples were collected.
-[col_date]; text; the date, in d/m/y format, that samples were collected.
-[as_date]; text; the date, in d/m/y format, that samples were assessed.
-[twig_age]; text; either 'c' or 'o''; the age of the twig (shoot) sampled (curr...