1368 MINERAL CYCLING IN A DOUGLAS FIR FOREST STAND a pattern of Rb | tall of 1963 (Fig. ‘The take ds FOREST FLOOR LEACHATES. 6001 SP appeared in application. Tl season was abot season. The upt ———- Ca 45 5004 BNL wie cUtiTe 400 300 ration ta the sei did ot appear limiting factoris soil system, becat cated a sufficient ] 200) at that time. 1 _ chemical separat activity. | - - 0 30} - SUIL LEACHATES 20! ro ae ae 10 Q ¥ x we i | oe " F ; C1OX)- 4 i es T Fic. 5. Concentration of radioactivity of Ca in forest floor and surface soil Jeachates. = INCHES a GM eet l Rb-86 100045 Lg 500, Q 12000 4 Vic. 6. Uptake patterns by Douglasfir trees of #3; 32 100004 and ™P. 8000, 60004 40004 (10%) 2000Q T T T T T T T tT APR MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB UNbva. UNIV. OF ess(19 p. - 2, J. S. Oxsox, V Jj. J. Davis, & . May "JUN JUL “AUG "SEP. oct NOV DEC. JAN FEBMAI MAR’ APR M MAY"JUN "JUL "AUG SEP ocTNOV bec JAN FCS CPM 1. J. D. Ovinerc ,