Jacob McCleland contributed reporting for this story.
With the unofficial start of the summer season behind us, the Missouri Department of Conservation is urging campers not to transport firewood - in an effort to stop the spread of the emerald ash borer.
"Don't move firewood," said MDC forest entomologist Rob Lawrence. "It's not only the emerald ash borer that we're concerned about, and it's not just ash wood. There are a lot of pests that are not native to North America that have gotten carried in here, and they hitchhike on firewood."
Nearly half of the trees on the grounds of the Gateway Arch will be removed and replaced with a different species.
The National Park Service said Thursday that more than 900 Rosehill ash trees will be taken out over concerns about the threat posed by the Emerald Ash Borer, a beetle that has killed millions of ash trees in 15 states. Officials at the Arch say the ash trees on the grounds are also showing signs of decline from urban factors like air pollution and less than ideal soil.