Know your islands
There are many plants around the world with the common name ‘Ironwood’, but the tree called Ironwood in the Cayman Islands is endemic – it grows in the Cayman Islands and nowhere else in the world. It is also on the World List of Threatened Trees.
Very little native woodland remains in the Cayman Islands and the few remaining stands of trees need to be protected. The following is taken from Wild Trees in the Cayman Islands by Fred Burton, with illustrations by Penny Clifford; photographs by Frank Roulstone.
Cayman’s Ironwood tree is a species unique to these islands, with two slightly distinct varieties, one on Grand Cayman and the other on Cayman Brac and Little Cayman. It is entirely different from the more widely known Krugiodendron ‘ironwood’, and is also a quite different species from Cayman’s Narrow-leaf Ironwood and Yellow Ironwood.
Ironwood has wood so heavy and hard it bends nails.
It is also brittle, so the trees often have broken branches and trunks. The leaves are not very distinctive, and you can confuse this tree with Wild Sapodilla; however unlike Wild Sapodilla, Ironwood’s leaves grow in exactly opposite pairs.
The trunk is buttressed at the base. The bark is typically coated with pale grey and charcoal black lichens, and flakes in irregular vertical strips. Burrs are often present, particularly near branching points. Ironwood fruits profusely in some years, and not at all in others: the flowers are white, and the oval berries ripen to a deep purple colour. Fallen berries are enthusiastically eaten by iguanas.
This is a tree of rocky woodlands, which grows best in areas close to a fresh water table. In higher rocky areas the trees grow more slowly, and develop hollow and split trunks.
Ironwood’s main traditional use was in building houses. Ironwood logs were cut and shaped by hand into 13 foot, 4-by-4 inch pieces, and used as the foundation posts on each corner. The wood is extremely strong and termite resistant, and also makes good fence posts. You can easily start your own Ironwood from seed, but don’t expect fast growth!
Protect Cayman trees and encourage Cayman Wildlife! For more information, to share your knowledge or if you would like to get involved with the many activities in the National Trust’s Know Your Islands Program, please visit www.nationaltrust.org.ky or call 949-0121.
Last week’s answer: A propagule is a seed that grows from a mangrove tree that helps the plant to take root and grow somewhere else.
Trivia question: What form of marine life causes sea itch?
Look for the answer in next week’s column.
The weekly column from the National Trust is submitted by Marnie Laing, Education Programs Manager at the Trust. The Trust can be contacted at 949-0121 or via email at [email protected].