Pursue this essay for the sake of curiosity.  I write it in part because I am in south Florida, and in part because of the resources now available on the World Wide Web.  Mostly I write it to express wonder about the creation.  Nature really is an antidote to boredom, but only if one chooses to look a bit more closely and always questions the conventional wisdom.  Of this world we know but a little, and much of what we know is wrong.  Still, it is all there in front of us.  We may not have the genius of Darwin, but we can still have insights into the mechanics of the world if we look carefully and with wonder.  Even if we don’t, we may enjoy watching the creation in action. 

Walking yesterday afternoon with friends through a neighborhood in Bonita Springs, Florida, we had much to enjoy.  A cold front was pushing through and producing lines of grumpy clouds and the occasional shower.  The atmosphere was dynamic and at times it ruffled our hair and sprinkled rain on us.  Development has recently altered the landscape here, but the slough was left in marsh and swamp.  Small flocks of ibis and egret fished there among the houses.  Away from the slough, two-year-old plantings within the condominium community have become well established.  I noticed that some effort had been made to utilize native plants, and these are doing especially well. 

Among them were some small tough-looking trees planted in a line along the road.  With small leaves and stiff-looking twigs, the branches scarcely swayed in the wind.  It could have passed for live oak, but I knew it wasn’t and closer examination found that its leaves were smaller than those of the oak and wider at the end away from the stem.  The twigs were armed with spiky thorns.  I guessed it was a bumelia and broke off a small sprig to take home.  There, checking my Golden Field Guide, Trees of North America, I identified it as tough bumelia, Bumelia tenax.   A tropical and semi-tropical species, its range extends up the Florida peninsula and reaches the South Carolina coastal plain.   It is a fine, if bushy, tree.  I had met it before in the hammocks of south Florida but somewhat forgotten it.

Tough bumelia is one of about fifty species of evergreen or semi-evergreen trees and shrubs with small simple leaves that grow in south Florida and create an identification challenge for the field botanist.  I grew up in south Florida and am still overwhelmed at times by all of these small-leaved trees that crowd the hardwood hammocks of the Everglades and Florida Keys.  The trees are easiest to approach in winter when they are not surrounded by arthropods that bite, sting, or simply crawl over you.  Also in the winter one also does not sweat so much when struggling through the dense hammocks.  But, in winter, these trees are unlikely to be in flower or in fruit, and without these additional organs to provide clues, the species are most difficult to identify. 

Now, I had already again identified this species and I had observed that it is now cultivated and grows well on the arid banks along the roadway.  Good to know.  I was curious to learn what other information is now available on the web.  Going there, the first thing I learned was that it has a new name.  Blame the taxonomists!  Good arguments can be made, I’m sure, but we old-timers are saddened that we no longer know the names of old friends.  The common names, bumelia or tough bumelia still hold, but the scientific name is now Sideroxylon tenax.  It seems there has been a marriage of sorts between the genera Sideroxylon and Bumelia, and most bumelias took the name of Sideroxylon.  

Sideroxylon (iron-wood), an oxymoron, probably refers to the wood of another species, but this species does have firm wood that is difficult to work.  Given its small size, it has seldom been used for lumber except for fence posts.  The genus includes the false mastic, a much larger tree also found in the United States only in south and central Florida that is of more value.  The genus is in the sapote or sapodilla family.  This largely tropical group has as its most famous member the tree sapodilla, the source of chicle for chewing gum.  A native of southern Mexico, sapodilla is rarely grown as an ornamental tree in Florida.  Tenax means gripping, stubborn, or firm and certainly describes this tree well in many respects.

Another name that I did not know is tough bully.  This is probably more an English than American name, but also seems appropriate, perhaps more so now that bumelia is no longer applicable scientifically.  A short article I found on the web (source:  the journal The Palmetto) mentions that its tough branches have a pattern “that shows character.”  Another name that I do remember is tough buckthorn.  Today in the nursery trade it is sometimes called silver buckthorn.  I can’t find the origin or meaning of bumelia.  This may be partly because it is no longer a valid genus name for this group of tough berry producing shrubs and shrubby trees. 

Before tough bully was domesticated it ran wild in the south Florida hammocks and still does so in what is left of them.  It needs to be tough to live there.   It is armed with thorns, bears a viscous sap, and has leaves that are fuzzy and probably somewhat toxic.  These attributes are necessary for survival in the tropical jungle.  The tree produces small clusters of relatively inconspicuous flowers and small plum-like edible fruits.  Neither make it particularly attractive to man, but both are useful if not essential to various insects and other animals that find home in south Florida.  Few if any of its relations with other organisms are known. 

Having little economic importance, it remains largely outside the sphere of influence of man.  Still, now being used in horticulture, it provides some wildlife habitat in the relatively sterile condominium communities that have sprung up all over south Florida.  People may enjoy its structure and find curiosity in seeing that its leaves bear light rusty color fuzz underneath.  A rare passerby may sample its sweet if small fruit. 

More likely, a passing naturalist will recognize the tree and smile knowing that here is a plant that has survived in a fashion the massive removal of native vegetation from south Florida.  He may consider it a puzzle to identify and reconsider its status in the modern world.  Mostly he or she will be blessed by its presence. 

Drafted March 1, 2009
Completed March 17, 2009