Park Planners and Plans
At the turn of the century the Senate Committee on the District of Columbia, chaired by Sen. James McMillan of Michigan, sponsored a study of Washington's parks. The McMillan Commission, as it was known, consisted of four prominent civic artists: architects Daniel H. Burnham and Charles F. McKim, sculptor Augustus Saint-Gaudens, and landscape architect Frederick Law Olmsted, Jr. Their report, The Improvement of the Park System of the District of Columbia, was edited by Charles Moore and published in 1902. With the strong advocacy of the Commission of Fine Arts, established in 1910 with Burnham, Olmsted, and Moore as initial members, the report had great influence on the later development and expansion of parklands in and around the city.
Rock Creek Park, the commission found, was among the areas needing improvement: "This territory, beautified by nature, is undeveloped, save for a few roads, the location of which was obvious; and before the public can fully realize the advantages of the purchase Rock Creek Park must be improved according to a systematic plan prepared by landscape architects." 
The report cautioned against enlarging the park's major artery, Beach Drive:
Narrow as the present road is, and skillfully as it was built, there are several points where it has very appreciably injured the scenery, and to widen it by any considerable amount would be a calamity. It is true that the value of the park scenery depends absolutely on making it conveniently accessible to the people, but nothing can be gained if the means of access destroys the scenery which it is meant to exhibit, and we believe that as wide a road as the future population is likely to demand would injure the character of the valley irremediably. Possibly the solution is to be found in the ultimate construction of another and wilder drive, or drives, high enough on the valley sides to leave the wild sylvan character of the stream at the bottom of the gorge uninjured, but yet within site and sound of the water and seeming to be of the valley. Such a road would doubtless require more grading, would cost more, and would destroy more trees and more square yards of pretty under-growth than a road at the bottom of the gorge, but the damage of the latter would be done at the vital spot. It would be the pound of flesh from nearest the heart, while the former would compare with the amputation of a leg. 
The commission recommended six additional land purchases totaling 303 acres to prevent overlooking crests from being developed and to take the park up to boundary streets separating it from adjacent property. It also advocated western extensions along the Soapstone Branch and Broad Branch tributaries, in the latter case to Fort Reno. 
Whereas the McMillan Commission only touched upon Rock Creek Park, being more concerned with the monumental city core, the Olmsted Brothers report ordered by the Board of Control in 1917 focused on its development and expansion. The Olmsted Report was completed in December 1918.  Its tone was set by its opening sentence: "The dominant consideration, never to be subordinated to any other purpose in dealing with Rock Creek Park, is the permanent preservation of its wonderful natural beauty, and the making of that beauty accessible to the people without spoiling the scenery in the process."
The report spoke of the park's two kinds of scenery--the larger landscape pictures and the intimate details:
These two sorts of scenery are not peculiar to Rock Creek Park, but in this beautiful valley with its many ramifications they are found in a high degree of perfection and in almost unlimited variety. It is the extraordinary combination of this circumstance with the proximity of the valley to a great city that gives to the Park its unique value. This is the value which was first preserved by Act of Congress for the benefit of all people. It is now and always will be the only value that can justify the maintenance of this great natural park.
The approach taken by Olmsted Brothers was to divide the park into defined landscape units, based on the vegetation that should prevail in each, and recommend measures for their enhancement and maintenance. Artificial development should in all cases be unobtrusive. Structures "should be so designed and located as to fall naturally into place as part and parcel of the scenery, and should never stand out as objects complete in themselves with the surrounding landscape becoming merely a background." Roads and trails "should always and unmistakably fit into the landscape as harmonious and subordinate parts of the scenery through which they pass." The report urged higher appropriations for park maintenance and development of a trained work force directed by "a man with a thorough knowledge of plants and forestry and above all with a keen artistic appreciation of the aims and possibilities of the work".
Accompanying the report were graphic renditions of recommended land additions, the landscape units, a system of park drives, and two proposed thoroughfares across the park (from Yuma Street on the west to Taylor Street on the east and from Utah Avenue on the west to Madison Street on the east). Land acquisition should receive priority, the report stated, especially on the west side from Pierce Mill north along Broad Branch nearly to Military Road, on each side of the narrow parkland strip then following the eastern tributary of Piney Branch, and at the northeast corner of the park.
The Olmsted Report was approved by the Fine Arts Commission, and in February 1919 Colonel Ridley announced its adoption by his office. "Nothing will be done hereafter in this park which is contrary to the letter or spirit of this report without specific approval in writing of the Officer in Charge of Public Buildings and Grounds," he ordered. At the same time he appointed a Rock Creek Park Board within the office "to assist the Officer in Charge in carrying out this development in a logical, continuous, and artistic manner." He detailed to the board two landscape architects on his staff: James D. Langdon (who had aided the McMillan Commission) and Irving W. Payne. They were to study the Olmsted Report, recommend on its implementation, and inspect and report on the work done. In the process they were to "consult freely with the landscape member of the Commission of Fine Arts taking every opportunity to present to him on the ground important details of work proposed." .
The landscape member of the Fine Arts Commission was James L. Greenleaf of New York, who succeeded Frederlick Law Olmsted, Jr., in 1918. At the commission's request, Greenleaf wrote Ridley at length with his comments and elaboration on the Olmsted Report.  He began by remarking on the perennial tension between preservation and use:
The Report declares the "dominant motives" of the Park to be to preserve its natural character of wooded valley and upland and open meadow, and to make it accessible to the public with the least, injury to this natural beauty. The two motives are inevitably opposed in any naturalistic park and increasingly so in proportion as a large city grows about it. Yet they must be balanced and adjusted, and this basic problem of adjusting artistic values and utility will arise continually in a thousand different places... Features of utility are necessary that the Park may be of use, but always there must be dominant a clear appreciation of its natural charm and a determination that it shall not be sacrificed. A recognition of this is vital to the preservation of values in Rock Creek Park.
"The rectifying of boundaries is an important matter and the Report rightly urges immediate attention to this before real estate values make the problem more difficult," Greenleaf continued. "The scenery is not panoramic, but instead the views are now chiefly those of woodland valley, bordered by hills wooded to the skyline. How unfortunate if this foliage skyline be replaced by obtrusive rows of buildings, gaping down into the Park...."
Of artificial structures in the park Greenleaf wrote:
All are inroads upon the natural scenery, more or less necessary it is true and therefore more or less justifiable, but to be handled with great caution and restraint. The advice given is to hold all structures down to simple forms, easily assimilated by the rustic scenery. This is to be commended if the idea be not carried too far. Designs made so rustic as to be a straining for that effect are unsatisfactory. A needed building, for instance, should not be obtrusive in its style of architecture but on the other hand, it should not be wildly rustic in a vain attempt to blend with woodland scenery Over all stands this general policy: limit artificial structures and keep them simple.
Greenleaf reluctantly accepted picnic grounds in Rock Creek Park but urged a strong stand against auto camping:
The Report recognizes the inevitable demand upon the Park Management for utilities when it suggests picnic groves at suitable places. If carefully policed such are not serious blemishes in the woodland and valley scenery, but frankly, they are danger spots in the higher development of the Park and should be firmly controlled Right now...comes the request from the Board of Trade for motor parking grounds in the Park where visitors by motor to the city can camp inexpensively while they are exploring the political centre of the United States. The park is for the public and open spaces in it are cheap. What more plausible? Need we state the serious objection to this proposal? Even in great parks like the Yellowstone such parking and camping places are necessary evils, that grate upon one's sensibilities. In the narrow, charming river valley of Rock Creek Park they would be an unmitigated, vulgar intrusion upon its sylvan beauty. If parking places for this laudable purpose are to be provided let the city take unused land that is not vital to scenic efforts. and so develop it. The valley of Rock Creek must be held inviolate.
Greenleaf's discourse to Ridley on the Olmsted Report reflected his concern that the Office of Public Buildings and Grounds was unequal to the task of implementing it. "Col. Ridley has difficulties of organization and daily administration," he confided to commission chairman Charles Moore. "My fear is that the valuable ideas the Olmsted Report gives shall never bear fruit under the deadening influence of daily routine." 
Moore was also inclined to criticism of the park's management under Ridley's office. In a letter to Olmsted in December 1921 he wrote, "It seems to me the park has been rather neglected in various ways, and the Commission wants to give the park particular attention during the next year." 
The following March Greenleaf expressed the commissions sense in a letter to Ridley's successor, Colonel Sherrill. "There can be no doubt that serious damage is occurring and this damage can be checked solely by intelligent and thorough handling," he wrote, calling for prompt suppression of weed growth. "There is a hill-side at a western entrance to Rock Creek Park which, with its cedars rising against the sky was reminiscent of an Italian hill-side. When I saw it three years ago, these cedars were shrieking under the throttling grasp of wild honey-suckle and tree weeds. Now as one passes he hears only a smothered moan. I call that hill-side 'The Tragedy of the Cedars.'" He urged Sherrill to study the Olmsted Report on this and other matters: "Its words as to a permanent trained force, and control by a man of imagination and artistic feeling and training withal, are as apples of gold in a silver dish." 
Sherrill did not take kindly to Greenleaf's implications of mismanagement and neglect. "The line of procedure indicated in your letter has been consistently followed for many years, and the report of Mr. Olmsted, with which I am entirely familiar, has been of the greatest service in administering the park...," he retorted. "There is no lack of a trained force, or of control of a man of imagination and artistic feeling in handling the matters connected with Rock Creek Park. The only difficulty is, and has been, that appropriations adequate to accomplish all the necessary work cannot be secured for the purpose." Nevertheless, he wrote, an expert forester recommended by the Forest Service had been employed by his office in the park for the past year and had accomplished much recommended by Olmsted. Sixty percent of the dead chestnuts had been removed and their areas replayed with more than 25,000 seedling trees. 50 acres north of Milk House Ford had been cleared of weed growth, and three acres around Fort DeRussy had been cleared of shrub pine to free the cedars. "In view of the above," Sherrill concluded, "I am sure you will agree that the administration of Rock Creek Park is not devoid of intelligence as intimated in your letter." 
Greenleaf hastened to assure Sherrill that he had meant no personal criticism and appreciated the work done. But criticism of Rock Creek Park's management continued. It would be repeated by professional representatives of the bureau succeeding the park's military government, the National Park Service, a dozen years later.