• Thirty-two permanent field plots were established in limestone forest and 14 in volcanic forest.
  • The forest area on Guam occupies approximately 63,830 acres, with limestone forest accounting for about 70 percent.
  • About 18 percent was urban, including roads, towns, airstrips, and military facilities.
  • We estimated gross tree stem volume to be about 91 million cubic feet.
  • About 21 percent of the trees sampled exhibited some form of physical damage.
  • decay was found in nearly one-third.
  • Sixty-four percent of the damage cases were attributed to weather or falling neighbor trees.
  • The average number of tree species per sixth-acre plot was about four in both limestone and volcanic forest types.
  • Forty-eight tree species and about 140 understory species were measured.

Map of Guam showing forested and nonforested areas