''Xanthostemon verdugonianus'', commonly known as mangkono or Philippine ironwood, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...

in the family

Myrtaceae Myrtaceae (), the myrtle family, is a family of dicotyledonous plants placed within the order Myrtales. Myrtle, pōhutukawa, bay rum tree, clove, guava, acca (feijoa), allspice, and eucalyptus are some notable members of this group. All ...

. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the islands of the

Visayas The Visayas ( ), or the Visayan Islands (Bisayan languages, Visayan: ''Kabisay-an'', ; Filipino language, Filipino: ''Kabisayaan'' ), are one of the three Island groups of the Philippines, principal geographical divisions of the Philippines, a ...

Palawan Palawan (, ), officially the Province of Palawan (; ), is an archipelagic province of the Philippines that is located in the region of Mimaropa. It is the largest province in the country in terms of total area of . The capital and largest c ...

, and northeastern

Mindanao Mindanao ( ) is the List of islands of the Philippines, second-largest island in the Philippines, after Luzon, and List of islands by population, seventh-most populous island in the world. Located in the southern region of the archipelago, the ...

. It is valued for its extremely durable and heavy timber. It is threatened by

habitat loss Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

Names

Mangkono (also spelled mangkuno or mancono) is also known as ''palo de hierro'' ("iron wood") in Spanish. It is also known as Magkuno (Magcuno) or Makano (Macano) in Surigaonon; and Magkuno or Tamaulauan in

Visayan Visayans ( Cebuano: ''mga Bisayà'' ) are a Philippine ethnolinguistic family group or metaethnicity native to the Visayas, to the southernmost islands south of Luzon, and to a significant portion of Mindanao. They are composed of numerous di ...

Description

Mangkono has a maximum recorded diameter of around , and a maximum recorded height of . However most trees rarely exceed in diameter and in height. The trunk is usually highly irregular with frequent branching. The bark is slate white in color and has a peeling appearance. The

sapwood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin that ...

is usually pale reddish in color while the

heartwood Wood is a structural tissue/material found as xylem in the stems and roots of trees and other woody plants. It is an organic materiala natural composite of cellulosic fibers that are strong in tension and embedded in a matrix of lignin t ...

is deep red to brown. The leaves are around in length, and in width. They are dark green in color on the upper side and pale whitish green on the underside. They have a smooth, leathery texture. They are simple and are arranged alternately. The inflorescence is borne at the ends of branches. They are bright red in color and spring from the apex of the peduncles. Each inflorescence has multiple peduncles, each with 3 to 6 flowers, for a total of 13 to 20 per inflorescence. Around 12 fruits develop from the flowers. The fruits are dehiscent and septicidal, with two or three sections that open when ripe to disperse small semicircular seeds.

Timber

''Xanthostemon verdugonianus'' is known to be the hardest Philippine hardwood species. Cutting a 70-cm thick tree with axes normally requires three hours, but cutting a Mangkono tree with the same diameter usually takes two to four days. Diamond-point saws have been used exclusively but a great volume of water is needed to counter overheating. Because of its inherent hardness and high density, Mangkono has long been recognized as a substitute for the world-famous ''

Lignum vitae Lignum vitae (), also called guayacan or guaiacum, and in parts of Europe known as Pockholz or pokhout, is a wood from trees of the genus '' Guaiacum''. The trees are indigenous to the Caribbean and the northern coast of South America (e.g., Co ...

'' (''Guaicum officinale'' L.). Mangkono is an excellent material for the bearing or stern bushing of a steamship's propeller shaft. Its other uses are as rollers, shears, saw guide blocks, tool handles, novelties, poles and piles for wharves and bridges, and posts for houses.

Conservation

The tree is rare and is classified as Vulnerable by the

IUCN The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the status ...

due to overharvesting and habitat loss.

References

verdugonianus Endemic flora of the Philippines Vulnerable plants Taxonomy articles created by Polbot Taxa named by Celestino Fernández-Villar {{Myrtaceae-stub