The effectiveness of small structures such as rock and brush spreaders, gully plugs, and small diversion dams is less difficult to evaluate since it is possible to observe how the structures act and the changes that occur in their immediate vicinity. Several studies of their performance have been completed, and the results generally have been disappointing. Two possible reasons can be ascribed for the ineffectiveness of these structures: (1) heavy damage to the structure and a high percentage of breaching or complete destruction, which makes proper maintenance impractical; (2) lack of reestablishment of vegetation, even in those areas where the structures have performed as anticipated.

An inherent weakness in many conservation structures is the fact that often it is necessary to design such structures without adequate hydrologic data for the area in which they will be built. This is done, not because conservationists are unaware of the importance of hydrologic data, but because

the data are not available and conservation programs have to be started to meet public demands. The inadequacy of many conservation structures so designed is reflected in a shortening of their effective life by sediment that arrived at a rate much higher than was anticipated. Structural failure or damage may be caused by unforeseen high runoff which would have been noted and planned for had adequate hydrologic data been available.

It is important to realize that all types of conservation measures such as those described must be evaluated on the basis of benefits obtained. The simple, cheap structure, such as the low spreader utilized so extensively in the early phases of the conservation program, has proven to be the most expensive since it produced negligible results. The larger, more expensive structures appear to offer great promise in localities where conditions are favorable.

In western United States the urgent need in conservation at present is to develop methods for refilling the gullied channels that dissect practically all of the once productive valleys. Probably no one method will be applicable; it will likely require a combination and adaptation of several methods. The effect on water supply of any type of conservation treatment will have to be considered. With increasing population and expanding use of water there is strong competition for available supplies. Even the minor demands for conservation programs will be scrutinized to make sure they are fully justified and that they do not impinge unduly on established rights of higher priority.

Conservation on rangelands is more of an art than a science, and the successful conservationist must therefore be alert to changes as they occur. Practices that show no measure of success should

BLM GOES TO THE JAMBOREE

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5 miles of sewer lines were constructed. Twelve miles of primary electric lines brought in 900 kilowatts to the camp.

Every precaution was taken to make the Jamboree healthful and safe. Approximately 200 medical doctors were on the Jamboree staff at sectional health lodges, and at the two 100-bed field hospitals on the grounds. In addition there were dentists, nurses, technicians, sanitation officers, ambulance drivers, and all other service personnel needed to man and run the hospitals and maintain good health standards.

It took a whale of a lot of planning to organize a program that would be both educational and entertaining to Scouts from every State in the Nation and practically every corner of the world. Thousands of volunteer man-hours went into the development of the fifth National Jamboree. Nearly 2 years before the Jamboree, Scout officials asked all major conservation and resource management agencies to help develop and present to the Boy Scouts at the Jamboree a comprehensive and educational story of conservation.

After a series of field planning sessions between the agencies, assignments were made within the conservation area. The Soil Conservation Service, Forest Service, Public Health Service, Weather Bureau, Geological Survey, Fish and Wildlife Service, National Park Service, Bureau of Land Management, and several private and Colorado State agencies were assigned specific responsibilities.

The conservation area of the Jamboree was divided into five sections: Geology and Weather, Soil and Water, Forestry and Range, Fish and Wildlife, and one section consisted of do-it-yourself conservation games run by a troop of Explorer Scouts.

BLM was asked to participate in two sections of the conservation area, Forestry and Range and Soil and Water. The Bureau had three exhibits in Forestry and Range and two in Soil and Water.

The Scouts passed through the conservation area in small groups on a rotational basis. Each exhibit was explained in an 8-minute talk. At the end of 8 minutes all groups rotated to a new exhibit. As they moved from one exhibit to another the Boy Scouts learned about geology, weather cycles, range management, watersheds, wildlife protection, soils, and the interrelationships between all of these things and conservation.

One of BLM's exhibits in the Soil and Water section, "Green Pastures," consisted of a table relief model of a public conservation area. It was demonstrated that conservation practices such as brush control, seeding, construction of ponds, and control of livestock use can often double the livestock carrying capacity of a range. The other

exhibit in that section, called "Walking Waters," was a working model of a BLM waterspreading project. The peculiarities of Western weather cycles were explained to the boys. And the necessity of detention dams and waterspreading systems to control erosion and provide sufficient moisture for the growth and development of grass 1: was pointed out.

Around BLM's exhibits the Scouts learned that grass, like timber, is a renewable resource. If it is managed wisely it will be replaced year after year with new growth to provide feed for livestock and wildlife.

In the Forestry and Range section BLM had three exhibits. The first, "Who Camped Here," gave everyone a chance to view a well-planned, properly cared for campsite next to a poorly designed, improperly cared for campsite. Scouts were encouraged to point out and discuss the good and bad features of the two campsites. Also, they were asked to offer solutions to such problems as litterbugs and destruction of public property. Participation was excellent, and often all ideas could not be voiced in the 8-minute rotational period.

The second exhibit in Forestry and Range, "What Grows Here," approached range management from the standpoint of how much meat an acre of grassland could produce. As the Scouts lined up under the sunshade in front of the exhibit they were confronted with a billboard showing a giant hamburger and a weight scale balancing grass and hamburgers. The BLM lecturer told how many bales of hay and acres of grass it would take to produce hamburgers for all of the boys. The Scouts were told how proper range management produced more grass for livestock and wildlife and thereby made more meat available for everyone's table.

"Visiting a Range" was the third BLM exhibit in Forestry and Range. In glass-paneled boxes, the Boy Scouts could see entire plants, from roots to leaves, growing under conditions which represented overgrazing, no grazing, and proper grazing. The boxes of grass were prepared for BLM by Colorado State University.

In the do-it-yourself conservation section Scouts could use a geiger counter to find uranium, scale logs, see an oil drilling rig in operation, and participate in many interesting games.

There were many things outside of the conservation area for the Boy Scouts to see and do. They indulged in Indian sand painting, arrowhead making, wood carving, tin can cookery, and many other interesting activities.

During the Jamboree everyone had an oppor

HISTORIC PIKE'S PEAK can be seen behind the Forestry and Range

area.

tunity to witness an exhibition by one of the world's top precision flying teams. The Blue Angels of the U.S. Navy put on a breathtaking demonstration of wing-to-wing aerial maneuvers at speeds up to 600 m.p.h.

Some 200 cowboys competed for awards in calf roping, bareback riding, saddle bronc-riding, and bulldogging in a series of rodeos at the Jamboree.

As the Jamboree drew to a close Scout packs bulged with the trade goods from all over the world; uniform patches, medals, horned toads, rings, polished rocks, and fabrics were exchanged. And Scout memories bulged with recently acquired facts, friendships, and experiences that would be cherished for many years.

The 1960 National Boy Scout Jamboree was an exciting and rewarding experience. To the agencies who cooperated in presenting the story of conservation it was a challenge met and a job accomplished.

For many people it was the first time they saw the complete field of natural resource management presented in a sense of harmony and cooperation. And that is the essence of conservation. End

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