HALEAKALA OVERNIGHTER — The Friends of Haleakala National Park will conduct a service trip Nov. 17-19 to weed heterothica at Crystal Cave washout area, with stay at Kapalaoa Cabin. Call 808-248-7660 for information and reservations.

MANANA TRAIL CLEARING — Sierra Club and O'ahu Invasive Species Committee service project at 8 a.m. Nov. 10. Meet at trailhead at end of Komo Mai Drive. Bring hiking boots, long pants, rain jacket, water, lunch, hat and sunscreen. RSVP to 286-4616 or oisc@hawaii.edu.

ARBORETUM WORK PARTY — Lyon Arboretum holds a volunteer work party at 8 a.m. on the first Saturday of each month. Meet in parking lot; closed-toe shoes, bug repellent, hat, gloves recommended.

KOKUA HALEAKALA — Haleakala National Park needs volunteers for trail maintenance, visitor assistance, weed control, cultural demonstrations, library work and clerical help. Apply at www.nps.gov/hale/supportyourpark/volunteer-opportunities.htm. Call 808-572-4487.

Send listings to: For the Environment, P.O. Box 156, Wailuku, HI 96793; cwilson@honoluluadvertiser.com; or fax 808-242-1520.