Sharpen your botanical knowledge with Dr. Mark Merlin, noted author and geographer. This trail features spectacular island views and a variety of native plants, many of which are featured in Dr. Merlin’s book, Hawaiian Forest Plants, available for purchase prior to the hike. Moderate, 3 miles. For adults. $4. Call Pauline Kawamata, 955-0100 ext. 18. www.hawaiinaturecenter.org.