Guaiacum sanctum

lignum-vitae

A close-up of a small light purple flower and pinnate leaves of a lignum-vitae tree, Guaiacum sanctum, at The Botanic Gardens at Kona Kai Resort in Key Largo, Florida

Lignum-vitae is runner-up for the hardest wood in the world, second only to the bull-oak of Australia, and is the densest wood in the trade. It is no wonder, then, that top-shelf police nightsticks were made of this wood. One of the major reasons lignum-vitae wood is so hard is the grain pattern, in which one layer is formed diagonally over the layer previous to it. These layers are so dense that the wood sinks in water, so choose this wood if you want to confuse your dog when playing fetch at the lake but don’t make a boat out of it.

Resin makes up about 30% of lignum-vitae wood by weight. Combined with its durability, this made lignum-vitae an ideal choice for a self-lubricating bearing solution that could even be used underwater on steamships because it resisted sea worms. The self-lubricating quality of the wood also made it useful to clock makers for use as bearings and gears. John Harrison famously used lignum-vitae in his grasshopper escapement innovation, which allowed for a clock’s power to be released in regular intervals. This mechanism was nearly frictionless and needed no lubrication because the parts involved were made from lignum-vitae. Harrison went on to develop the first reliable sea clocks, which allowed navigators to quickly and reliably determine longitude.

A close-up of the ripe yellow fruits of a lignum-vitae tree, Guaiacum sanctum, with the bright red seeds peeping through the three triangularly arranged yellow seed pods

Lignum-vitae was considered a panacea in Europe for a few hundred years after its introduction to Europe from the Caribbean as a cure for syphilis. The plant actually does not do anything to cure syphilis or ameliorate its symptoms but the fact that the disease appears and disappears in stages and does not have consistent symptoms (it is nicknamed “the great imitator”) may have caused problems with determining efficacy. Also, the most important bankers of the time, the Fuggers of Augsburg, became the principal importers of lignum-vitae, commissioning harvesters to cut down any trees they found to satisfy the demand for lignum-vitae remedies the Fuggers helped create to serve their financial interests, effectively Fugging over both the tree and people looking for a genuine cure. Lignum-vitae is still an endangered species today due to past exploitation but it has fortunately been able to recover some population strength, at least in cultivation.

Lignum-vitae wood was used to make lawn bowling balls and early full-size bowling balls, which must have been made from some very old trees, as the trees found in the Keys under fifty years old are still well under a foot in diameter. “Heavy balls” used in cricket during windy conditions are sometimes made from lignum-vitae. Tools carved from lignum-vitae include wood carver’s mallets, mortars and pestles. Belaying pins and deadeyes on many sailing ships have historically been made of lignum-vitae. The strong wood was used by Hardy Brothers of Alnwick to make their Greenheart fly fishing rods in the late-1800s. Lignum-vitae resin is still one of the principal reagents in tests for occult blood.

This is a plant very much at home here in the Keys. It requires soil with excellent drainage and tolerates salt spray as well as periods without rainfall quite well. Even under ideal conditions, this is a very slow-growing tree that matures to 30-40 ft. after many decades.