CORRELATION OF SELECTED SOIL INDICES WITH PLANT GROWTH ON HIGHWAY BACKSLOPES IN IOWA

IN AN ATTEMPT TO EVALUATE AND ANALYZE THE PROBLEM OF HIGHWAY BACKSLOPE REVEGETATION IN IOWA, A SURVEY WAS MADE OF BACKSLOPE EXPOSURES ALONG 3,500 MI OF HIGHWAY IN THAT STATE. SOME 55 ROADCUTS EXHIBITING DIFFERENCES IN VEGETATION AMONG THE VARIOUS ZONES WITHIN THE SAME SLOPES WERE STUDIED IN GREATER DETAIL. PLANT GROWTH WAS MEASURED ON 241 SAMPLING SITES WITHIN THESE CUTS, AND SOIL SAMPLES FROM THE SAME SITES HAVE BEEN DESCRIBED AND ANALYZED ON 20 PRESELECTED SOIL PROPERTIES. A DESCRIPTION OF BACKSLOPE MATERIALS OF MAJOR OCCURENCE IS MADE ON THE BASIS OF ANALYTICAL DATA. CORRELATIONS BETWEEN PLANT YIELD AND SOIL PROPERTIES INDICATE THAT OF ALL FACTORS NITRIFIABLE NITROGEN AND AVAILABLE PHOSPHORUS EXERT THE LARGEST POSITIVE INFLUENCE ON PLANT GROWTH IN BACKSLOPE MATERIALS OF LOW CLAY CONTENT. IN THE SAME GROUP OF MATERIALS EXCHANGEABLE HYDROGEN AND SAND CONTENT ARE THE MAIN NEGATIVE FACTORS. PLANT GROWTH ON CLAY-RICH MATERIALS (GUMBOTIL, FERRETTO, AND B HORIZONS) APPEARS TO BE INCREASED BY AVAILABLE AND NITRIFIABLE NITROGEN AND DECREASED BY HIGH CAPILLARY POROSITY AND SAND CONTENT. /AUTHOR/

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  • Supplemental Notes:
    • Vol 38, pp 622-637, 7 FIG, 5 TAB, 25 REF. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.
  • Authors:
    • Peperzak, P
    • Shrader, W D
    • Kempthorne, O
  • Publication Date: 1959

Media Info

  • Media Type: Digital/other
  • Monograph Title: Proceedings of the Thirty-Eighth Annual Meeting of the Highway Research Board, Washington, D.C., January 5-9, 1959
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00204843
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Sep 19 1971 12:00AM