Sunday, July 25, 2010

By robin robinson Key West Garden Club

Irode my bike by a tree covered with an incredible fountain of cascading yellow blossoms on the corner of Leon and Laird streets. Making good use of the seldom-used stop sign at the corner, I pulled my bike to a full, get-off-the-seat stop, pulled out my camera and recorded this dazzling blond stranger.

This was the golden shower tree (Cassia fistula L.), one of many plants in the Cassia group, this one without a leaf on it, but covered by racemes -- branching "axis" with flowers having short floral stalks equidistant along them. On this tree they were as much as 40 inches long, made up of 2-inch flowers. There are five petals that are of equal size and shape on each flower.

When the deciduous leaves do emerge later in the year, they are oval, dark-green and pinnate, with three or four pairs of leaflets approximately 7 inches in length. Think of Bahama cassia or Bahama senna.

That brings us to the subject of reclassification. Botanists in their ongoing classification wars have renamed the cassia to senna. Look for it to be called both names during the transition. Senna means thorny branches, but this tree has no thorns. The L. designation indicates that cassia is the original name given to the tree by famed botanist Carl Linnaeus.

The dark-brown seedpods are 18 inches long and 2 inches in circumference. The tree is named for this hollow-like tube (fistulo means hollow) that is filled with sticky pulp and divided into sections with a small, flat, brown seed in each section. There can be as many as 50 to 100 seeds in each seed pod.

One of the first recorded mentions of cassia is in the Bible, where Moses is ordered to make oil out of cinnamon, cassia, myrrh, sweet calamus and olive oil to anoint the [Arc of the Covenant.] The tree reported to originate in India is now native to much of Southern Asia and is the national tree of Thailand.

The historian Pliny records the spice trade from Egypt where a pound (327 grams) of cassia cost 300 dinars, equivalent to 10 months of work. It arrived across the Red Sea on "rafts without sails or oars."

Kasia is also a Greek name used by Sappho in a seventh-century poem.

Its herbal qualities were first mentioned by pharmacologist and biologist Dioscorides in his herbal book, "Materia Medica."

It has an equally long history as a folk remedy for more than a hundred different ailments.

Ayurvedic (traditional) medical practicioners in India have used it for thousands of years to treat everything from constipation to pimples. All parts of the plant -- the roots, bark, leaves, seeds, the pulp around them, and fruit -- are useful. It's an astringent, purgative and vermifuge (an agent to expel parasites).

It has been used to treat cancer, delirium, acid reflux, convulsions, epilepsy, leprosy, skin diseases, syphilis, rheumatism, ulcers, fever, heart disease, flu, eye ailments and many more diseases. Despite the number of ways they can be used, the seeds are poisonous and require processing to make them safe.

The tree also is used for firewood. The wood is reddish, strong and durable. While it is suitable for cabinet and inlay work, it also can be used to make farm implements, posts, wheels and mortars because it is hard and heavy. The bark is used in tanning.

Considering how useful the tree is, it's a good thing that this blond bombshell grows quickly. It can achieve 70 feet in height and 40 feet in width in just a few short years.

It likes poor-nutrient, well-drained soil and is drought-and salt-tolerant, but cannot take a long freeze. With short cold weather it may come back when it gets warm. If the soil is too wet, the tree can get mildew, leaf spot or root diseases. In the U.S., it only grows in the frost-free Keys.

The golden shower tree likes pruning in order to keep a strong central trunk and develop a uniform crown. Its branches droop and should be pruned to an appropriate height. The tree has no pests or root problems. Bees and butterflies flit around its blooms.

It does not propagate well with cuttings, but grows from seed when treated with 15 minutes of sulfuric acid and soaked 24 hours in water. It also sprouts when the seed is scarified.

This golden beauty makes a gorgeous street tree or a specimen tree on large lawns. Plant it, and you will have people stopping to admire it. Everybody loves a blonde.

The Key West Garden Club welcomes volunteers to pull weeds, learn to propagate plants and play in the sandy soil at West Martello from 9 a.m. to noon Mondays.

Master gardener Robin Robinson was a columnist at the Chicago Daily News and syndicated by Princeton Features. This column is part of a series developed by the Key West Garden Club, http://www.keywestgardenclub.com. A compilation of her columns, "Plants of Paradise," is available at the Garden Club.