MACHINES AND FIRES IN THE SOUTH

ARTHUR W. HARTMAN.

After 30 years of effort by private, State, and Federal organizations to protect their forests against fire, some 97 million acres of the private wooded land in the South are under some kind of protection. An additional 15 million acres are protected by the national forest organization. More than 80 million acres of forest and potential forest land, however, receive no protection at all.

Of every 100 acres under organized protection by State forest services, an average of 1 1/2 acres suffer burns each year. As late as 1943, when fire suppression depended mostly on men with only hand tools, fires burned 29 million acres and destroyed values estimated at 72 million dollars.

The record was not good. Several explanations, if not excuses, can be given. Because fast-spreading fires can start in flash fuels in the South a few hours after a rain any time during 8 to 12 months of the year, forest lands are in almost constant jeopardy. Combinations of low humidity and high wind often create conditions of extreme hazard, when fires may burn with an intensity beyond the ability of men to control unless they have proper machines but, although yesterday's long lines of pick-and-shovel ditch diggers have been replaced largely by Powered trenching machines operated by a few men, there are still lines of sweating, exhausted men who try to stop the fires with shovels and rakes.

For the delays in getting machines for fire fighting, one can assign several reasons. Fires occur intermittently; during times of low hazard, the fighters are scattered to perform other tasks. In periods when burning intensity is not severe, fires are handled so easily that men may lull themselves into a false security. Funds and facilities were insufficient to meet the requirements of broad-scale planning, creating, testing, experimenting, as well as developing the special equipment needed for successful fire-line performance. And, as always, there was the human resistance to change.

Nevertheless, attempts were made to adapt the available machines to the need. Foresters and an implement manufacturer in Florida, for example, made over a heavy tractor-plow, which turned out to be useful under some conditions but expensive and too big to be easily moved from one fire to another. Elsewhere farm tractors were pressed into service. Men in Arkansas developed a pusher-type plow on a crawler tractor. Fire fighters in Texas made progress with a garden-tractor plow. Others used jeeps, or any vehicle at hand, to pull light plows and haul water tanks and pumps. With such makeshifts, however, nobody was satisfied.

Then came two developments at one time. The Civilian Conservation Corps, which had supplied so many trained and vigorous men for the work, was discontinued. Then, the war drained the towns and back-country of able-bodied men. The situation left one choice : Mechanize or burn.

State, industrial, and Federal foresters, despite wartime handicaps, began to attack the problem on the scale the situation demanded. The few previous trials and errors gave them some guides and principles, but they needed information, action, and decisions on five points : Thorough knowledge of the terrain, soil, cover, and fire behavior over all forested areas from the Carolinas to Texas; reports on the design and performance of equipment that had been tried out; goals for each general timber type; specifications of units that would give the results they were after; time and funds to test new ideas.

Several other essentials complicated their problem: All designs had to assure reasonable safety to the operators. Each unit had to balance the factors of least cost, lightest weight, fastest travel and operation, dependability, the widest range of use over a major area. The designs had to use standard parts and techniques of shop procedure to facilitate repairs and maintenance. Accessories, such as backfiring devices and communications, had to be identified, selected, or developed. The size, use, and organization of crew that would be most efficient and effective had to be determined. Men had to be trained.

All that had to be done quickly the forests and the world were burning up.

Information at hand or quickly accumulated provided several first principles: A plow-constructed, mineral soil line was superior to other types of fire lines. The multiple disk-type of plow was fastest and most efficient wherever it could be used. The middle-buster type of plow was next best on stony ground where the disks would not stand up. The crawler-type tractors were the most satisfactory power units. Multiple-drive transports were better than those with 2-wheel drives for back-country travel. The main uses of tankers in the region were to help hold the fire line at plowed lines, catch spot fires, and do mop-up.

Further investigations brought out that plows of five classes would meet most of the needs.

1. The heavy disk plow, of 2,500 pounds, for dense stands with luxuriant undergrowth of palmetto, shrubs, and grasses common to the lower Coastal Plain.

2. The medium disk, of 950 pounds, in the less dense belts of the Coastal Plain.

3. The light disk, of 475 pounds, where the fuel is principally the pine straw and grass found in the upper Coastal Plain and Piedmont.

4. The lightweight middle buster, of 475 pounds, in the stony ground of the lower hills and on Appalachian slopes of less than 25 percent grade.

5. The flyweight, cultivator type, of 125 pounds, in the open short-grass areas in the southwestern parts.

Heavy disk-type plows which would operate successfully were available commercially; the problems were to determine the lightest tractor that could ride down and pull the plow through the different densities of ground cover, and to design speedy transports that could haul the tractor and plow closer to the back-country fires. In the final assignment of locations, places were found for all sizes of tractors, from 22's to 50's. Hi-low trailers were designed in varied weights to fit their loads. They were rigged as prime movers, and ranged from 1/2-ton two-wheel drives to 2 1/2 -ton 6 x 6's, according to loads and travel conditions. Eleven of these assemblies were completed in 1944 and placed in service.

Meanwhile, a lightweight unit was being tested. A key specification for it was that the tractor and plow in combination must be light enough to be transported on a 1 1/2-ton truck. We found finally that a commercial 18-horsepower tractor, with several alterations, would fit the need. Then we designed a truck chassis to make loading and unloading easier. Seventeen of the units (called Ranger Pals) were assigned in 1944 to 10 high-fire-occurrence ranger districts. Experience with them in the field revealed opportunities to make further improvements, which we did. Twelve other lightweight units and 10 more heavy units were placed in operation in 1945. Radio receivers were installed in about half of the units. The development and field testing of a middleweight unit was under way.

Eight improved lightweight units and 10 heavy-transport units were added in 1946. Since then, 6 middleweight, 8 lightweight, and 2 fly assemblies, and nine 4 x 4 power wagon tankers have reached the fire lines. Most of them have sets for radio communication.

At the same time, several State foresters and private owners adopted some of the machines and worked to perfect others. Their difficulty, however, was that they had few pieces of equipment and large areas to protect.

Men on the national forests faced a like situation of not enough, and we had to choose between spreading the equipment generally or making some concentrations. To obtain the greatest use and protection and at the same time measure the economic aspects, we chose to favor the ranger districts that had the worst combinations of high fire occurrence and fast rates of fire spread. A number of other districts that were favorable for plow use were left without mechanical units. Because there were so many critical areas, we believed then that it was impractical to equip fully any one ranger district with what we have come to believe since is the minimum number of units.

By 1946, however, six of the worst fire districts had enough equipment to handle their situation on all but the most hazardous fire-weather days.

Meanwhile, experience produced improved tactics, increased the effectiveness of each unit, and made it possible to compare and analyze equipment, work, and trends.

One analysis brought together data for three fire seasons on seven ranger districts in Mississippi and Louisiana. The first was in 1940 (1941 records for two districts), when 315 fires were fought with muscle-power and the fire fighters were boys and men of the Civilian Conservation Corps well trained, well organized, and readily available, and with their own fast transportation. The second season was the same months of 1946, when 526 fires were fought on those districts with mechanical suppression units in numbers adequate to permit the proper strength on the larger fires but often inadequate for prompt attacks on additional fires.