The autograph tree, botanical name
Clusia rosea was introduced in Hawaii as an ornamental plant. The plant is a close relative of Mangosteens tree
and belongs to the family ‘Clusiaceae,named in the honor of 16th century Netherlands botanist Carolus
Clusius.
The plant is native to Florida and the Caribbean.
Other names for the plant are signature tree, pitch apple, and monkey apple
tree.
The tree gets its name from the ability
of its leaves to retain any scratch or writing for a very long time. Each leaf
is 5-8 inches in length, oval, thick and sturdy and shaped like a paddle. The
leaves resemble that of Magnolia. If you scratch the leaf with your nails or a sharp object, the upper dark green layer is peeled off and the lighter greenish/white
underneath layer is exposed, creating a contrast that is retained till the life
of the leaf.
Another unique thing about this species is it is part of the only genus of
plants capable of absorbing carbon dioxide at night.
The plant is long-lived perennial that can grow to
25-30 feet in height, but it really depends upon the trimming and potting and the ground conditions. Its drought and salt tolerant nature makes it an ideal choice
for landscaping in areas with less rainfall or sea-side homes.
The flowers are white or pink and
mostly bloom during the night, they sometimes remain open all morning, especially
on a cloudy day. The flowers turn orangish-brown as they mature and fall.
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| By Dick Culbert from Gibsons, B.C., Canada - Clusia rosea, the Autograph Tree flower., CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=34450558 |
The flowers are followed by green to
tan, fleshy, rounded, up to 3 inches (8 cm) in diameter fruits. They turn brown
to black on maturation and split open like a wood rose to reveal bright red
seeds between black resinous material.
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| The fruits |
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| Dried Fruit on the ground |
The black resinous material was used
in the early days to fill in the seams and crack of the boats. The red seeds are
very attractive to birds which also help in the dispersion of the seeds.
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| The seed pods open up |
The autograph tree is a strangler tree. The
tree is hemiepiphyte and can grow as an
epiphyte or from the ground. The seeds are dispersed by birds in the crotch of other trees sometimes as high as 20-25 feet. The seeds germinate and
send long banyan-like aerial roots toward the ground and establish other roots into
the interior of the host tree. Slowly the host tree is cut-off from receiving
nutrients and perish eventually.
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| https://www.flickr.com/photos/starr-environmental/24549985985/ |
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| [[File:Starr 011205-0021 Clusia rosea.jpg|Starr 011205-0021 Clusia rosea]] |
Hence, the Autograph tree is classified as an invasive tree in Hawaii. Gardeners are advised to remove autograph trees from
their property and not to plant new ones.
According to the Food and Drug
Administration database, Clusia rosea is a poisonous plant. The green fruits
are mildly poisonous, and so are the leaves. Consumption of fruits and sap will
lead to stomach and intestinal irritation, vomiting, and diarrhea.
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| The autograph tree |
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| The autograph tree |
