MONDAY

Tree Identification, 6:30 p.m. in Bangor

Join the Bangor Land Trust for its tree identification walk at the Walden-Parke Preserve. Email info@bangorlandtrust.org or call 942-1010 for more information.

SATURDAY

Science in the Park, Mount Desert Island

National parks use citizen scientists to learn about climate and ecosystems. Join scientists in Acadia National Park’s Sieur de Monts Nature Center for a day-long celebration of science in the park, with a dozen interactive stations. There will be a shuttle from Sieur de Monts to the Jackson Lab parking lot. The event is free but there is a cost for park admission.

Bar Harbor Brass Week, 7:30 p.m. in Bar Harbor

As part of the Acadia National Park centennial celebration, the alumni of Bar Harbor Brass Week will return for a free concert. Many are now professional brass musicians. Go to acadiacentennial2016.org for more information.

Alewife Run Paddle, 8 a.m. in Orland

Join the annual Alewife Run from Craig Brook National Fish Hatchery to Orland Village. Cheri Domina of Great Pond Mountain Conservation Trust and Karen Francoeur of Castine Kayak will lead paddlers in canoes and kayaks from the Alamoosook Lake beach for a leisurely 3.5-mile paddle down the Narramissic River, arriving in the village. One short portage around a dam is involved. Castine Kayak will rent and deliver a kayak for $20 for anyone in need of a boat. Call 866-3506. For details on catching the shuttle and more, visit www.greatpondtrust.org or call 469-6929.

UPCOMING

Maine Adventure Race, July 23 in Jefferson

The first Maine Summer Adventure Race will offer a full day or half-day of exploring the woods and lakes around Hidden Valley Nature Center. The race will involve teams of two, three or four competing in trail running, road and mountain biking, flat-water paddling and orienteering. For more information, go to MaineSummerAR.weebly.com or call 522-5630.

– Send event listings to dfleming@pressherald.com