Crowds, reservations, and fire danger all will be present in corners of the National Park System during the Memorial Day Weekend that is the traditional kickoff for summer travel.

Near the top of the hike up Signal Hill where Antigua’s last remaining rainforest gives way to rocky barrens, clumps of a long and deceptively pretty plant with a bright, citrus aroma sprout from the volcanic soil. It’s lemongrass — that ingredient we all love in Thai curries and soups, but an invasive species that grows fast and burns easily on this Caribbean island because of the high oil content in its leaves.

Calgarians are being encouraged to help offset the impact of personal vehicle use on wildlife and the environment by taking transit to Banff National Park.

The National Park Service is facing a water conundrum: some parks have too little, some parks have too much. While an historic drought continues to parch much of the Western United States, a new report from the National Oceanic and Atmospheric Association predicts that sea levels across the United States will rise, on average, 10-12 inches by 2050. In other words, from Maine to Florida to Texas and all the way up to Alaska, there are more than 100 national park units threatened by the slow siege of rising coastlines.