Savannah is noted for the beauty of its street trees and its squares, and many of the species chosen, historically and to this day, have been selected with their aesthetic qualities in mind. At times in Savannah's history, however, certain plants have been chosen for their practical benefits too.
In the late nineteenth and early twentieth centuries, Savannah's Park and Tree Commission did not like people to walk on the grass. The city's thin, sandy soil gave little for the grass to hold on to. It only took a few dozen people cutting across the square instead of using its paved walks before the grass was worn away.
The Commissioners despaired at the unsightly tracks this habit left, and the city didn't have enough money to re-sow all the squares with new seed every year.
They tried appeals to reason: admonishing Savannah's citizens to take greater pride in the appearance of their city, and to do their part to preserve the appearance of the squares by walking only on the paths.
When that failed, they tried making it illegal to walk on the grass. The city duly passed ordinances imposing fines or incarceration against people who cut across the squares.
These ordinances were usually enforced for about a month before the police tired of making example cases (unfortunately, in this period, police almost exclusively targeted black culprits rather than white ones when making their arrests), and then allowed to lapse.
While holidaying in Florida one summer, one of the Park and Tree Commissioners, Philip Daffin, hit upon a solution to this intractable problem that had yet to be tried in Savannah.
There, he noticed that several hotels employed a very sharp and forbidding plant, the Spanish dagger, or Spanish bayonet, also sometimes known as bear grass (Yucca gloriosa), in their plantings, where they wished to discourage trespass on the grass.
An aptly named plant, the Spanish dagger consists, like many members of the yucca family, of a rosette of stiff, pointed leaves with rather sharp edges that attack all who come near them.
Though Daffin apparently first noticed the species in Florida, it is in fact native too to the Georgia and South Carolina coasts, growing in the dunes and sea islands of that region.
Daffin decided that these yuccas, planted out as a barrier at strategic places on Savannah's squares, might finally solve the problem of people walking on the grass. Unlike Savannah's policemen, its policies were fair, and better still, it was always on duty.
Upon his return home, Daffin suggested that the Commission adopt them in its planting. It took a while to establish the plants in the squares, as in their early youth they suffered from the same problem as did the grass, being extremely vulnerable to trampling. Those Savannah citizens who walked on the grass, walked likewise on the delicate young Spanish daggers, not yet old or hard enough to defend themselves.
Eventually, some of the plants grew well, though unfortunately never in sufficient numbers to entirely put off the city's determined grass-walkers. Few Spanish daggers can be seen today in Savannah's parks and squares; the tracks across the grass, however, have, in many places, endured.