Decline of Ohia (Metrosideros polymorpha) in Hawaii: a review

Author:

Hodges, Charles S., Adee, Ken, Stein, John D., Wood, Hulton B., Doty, Robert D.

Title:

Decline of Ohia (Metrosideros polymorpha) in Hawaii: a review

Periodical:

General Technical Report (GTR) PSW-86

Year:

1986

Subject:

Ohia Metrosideros polymorpha Ohia dieback

Summary:

Portions of the ohia (Metrosideros polymorpha) forests on the windward slopes of Mauna Loa and Mauna Kea on the island of Hawaii began dying in 1952. Little mortality has occurred since 1972. About 50,000 ha are affected by the decline. Individual trees exhibit several symptoms, from slow progressive dieback to rapid death. Seven types of decline have been identified on the basis of differential response of the associated rainforest vegetation. Two of the types, Bog Formation Dieback and Wetland Dieback, make up more than 80 percent of the decline area. The decline has affected bird populations and plant species in some areas, but has had no major effect on runoff or water quality. Ohia decline appears to be a typical decline disease caused by a sequence of events. Poor drainage is probably the major cause of stress and is followed by attack of the ohia borer (Plagithmysus bilineatus) and two fungi (Phytophthora cinnamomi and Armillaria mellea), which kill the trees. Except for controlling introduced plants and feral animals that spread them, little can be done to ameliorate the effects of the decline.

URL:

http://www.treesearch.fs.fed.us/pubs/27052

Date:

1986

Collection:

Monographs