-94-

Committee on Survey Reports, Maps, Technique of Mapping.

No formal report by the Committee on Soil Survey Reports, Maps ,Technique of Mapping, has been prepared. The following statementis submitted by the Chairman of the Committee as introductory tothe commit tee 's part of the program:

The program of the Committee is largely devoted to thetechnique of soil mapping. THe phase of the c o m m i t t ' s interestis stressed at this meet ing, tKe-.use of its importance to ourwork and because the other phases have been d i scussed pro andcon, in and out of our meetings, since the establishment of theassociation.

While the fundamental concern of the Soil Survey is thefield study and classification of soils, never theless the f u n d sof the Soil Survey, both in the field and in Washington are large-ly expanded in the making and publication of soil maps. The soilsurveyor in actual practice is largely busied in keeping his cor-rect orientation and location) in ferreting out soil boundaries,in plotting those soil boundaries along with such other topogra-phic fea tu res as are considered pertinent end appropriate to thesoil map. He is fur ther charged with the responsibility of pre-senting his map material in legible condition. We art familiarwith the old time methods of accomplishing all tnie: with theplane table and its accessories; the U. S. G. S. topographicsheets; the straight-line methods, which are comfortable enoughin open straight-line country, but a source of irritation andbloodshed in tangled regions of logs, dense brush and windfalls.These methods date back to the year 1900, or earlier. About theunly marked change in methods for 25 years or more was the sub-stitution of the automobile for "Dobbin end the one-horse shay",which was fo rced upon us by Henry Ford, et al.

During 1 he late unpleasantness in Europe, a number of us tookadvantage of the opportunities o f f e r e d by the United States Armyto participate in the hostilities. Some of us ventur ing into theair, acquainted ourselves w i th the possibilities of using aerialphotographs in mapping. O t h e - o rgan iza t ions , including the U. S.Geological Survey, took up the development of aerial mapping. TheSoil Survey used odds and ei ,r is of a e r i a l photographs and base mapsprepared in part fro-a aerial photos. ut t imes, but the firstsystematic photography of nr. en t i re county for soil mapping pur-poses, was tha t of Jennings C o u n t y , Indiana, in November , 1929.

The use of aer ial p h o t o g r a p h s in Indiena has continued.Diff icul t ies have bc-e;n iwi, whioh is na tura l at the start of anynew enterprise or m e t h o d , but , largely due to the persistence of Mr.T. M. Bushnell, these- obstacles n* ve b e e n met and mostly eitherovercome , pushed aside or burrowed u n d e r , all of which will be

-95-

h e r e a f t e r set for th by Mr. Bushnell h imsel f . The inttrest in thisuse of aerial photographs hus increased. They have been used inthe Michigan Land Economic S u r v e y , in Porto Rico, in New Y o r k ,Louisiana, sno elsewhere in the coun t ry , The methods , advantagesand disadvantages will be d iscussed by Mr. Bushnell and Mr.Schoenmann•

The use of oerial photography dn soil mapping, wha teve r maybe its shortcomings, does have the e f f e c t of stimulation to act iveminds. This menta l stimulation may be r ega rded as insanity,intoxication, or religious f e r v o r , or it may be regarded as in-centive to the development of a method of soil mapping which willincrease the reliability of our soil maps, and m a y , in the f u t u r e ,lead to economy in their preparation end publication.

Mark Baldwin, Chairman,W. J. Geib,L. H. Smith,W. E. Hea rn ,A. T. Sweet,