GEOGRAPHY OF CENTRAL FLORIDA 285

 forests or prairies are much more extensive than cultivated fields it is cheaper to fence the crops and give the cattle and hogs free range than it would be to confine the cattle, and the law gives the animals this freedom in most parts of Florida), some method of improving the road must be adopted if there is much traffic on it. The cheapest road-surfacing material is pine straw (said to have cost about $35 a mile by 1915 prices), which has been used to a considerable extent where there is neither clay nor rock within easy reach. This is ordinarily renewed every year or two. Near sawmills and planing mills sawdust and shavings are often used in the same way.
 In many places, particularly in the lake region, sandy clay occurs within a few feet of the surface, and when spread out to the proper thickness and rolled it makes a very good roadbed. In several other regions limestone rock is available, and gives still better results. In the pebble phosphate country a sandy rock that forms part of the overburden in the mines is sometimes used in the same way. Even in the eastern flatwoods and the lake region there are a few deposits of marl near the surface, and that makes as good a road as clay. Near the coasts oyster shells, either from living reefs or from shell mounds, have long been utilized by road-makers, as have other species of shells occurring in the mounds. Before the days of automobiles the shells were usually simply spread out over the surface of the road from time to time and left to be ground up and compacted by wagon wheels.
 Since automobiles became common there has been a great development of permanent roadways, and where local supplies of rock, clay, etc., are inadequate, brick and asphalt (fig. 27) have been imported from other states or countries in large quantities. At the present time there is perhaps no equal area in the world that has better roads in proportion to population than central Florida. But in the building of highly improved roads in recent years there has been a regrettable tendency to locate them as much as possible along section lines or parallel thereto. This practice doubtless simplifies negotiations with land-owners, and requires less mental exertion than adapting the roads to the topography, but it makes them more expensive to build and maintain and wastes the time of people using them (for two sides of a square are over 40%