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Soils were collected from 2-year (2-y) and 3-year (3-y) old red-pine seedling plots in two tree nurseries, Hayward in the north and Wilson in the southwestern part of Wisconsin State respectively, and equilibrated with 0.01 M Ca(NO3)2 for soil solution Zn and Mn (solu-Zn and Mn), and with 0.01 M Ca(NO3)2+0.005 M EDTA for soil adsorbed Zn and Mn (ad-Zn and Mn). Buffering capacity of soil Zn and Mn (b-Zn and Mn) was obtained from the ratio of ad-Zn and Mn to the solu-Zn and Mn. The concerned traces in pine seedling needles (ndls), stems(sts) and roots (rts) were simultaneously measured. The results obtained show that:About 60% of solu- and ad- Zn ranged from 0.2 to 0.4 and from 1 to 2μ/g soil respectively. About 70% of b-Zn was within) 3-10.The highest content of solu-Zn compared with the lowest showed a discrepancy of more than 10-fold. The two forms of soil Zn were commonly higher in Wilson than in Hayward Nursery.About 80% of solu-, ad- and b-Mn were within 3-10, 5-5.8 μg/ g soil and 1-2 respectively
Soils were collected from 2-year (2-y) and 3-year (3-y) old red-pine seedling plots in two tree nurseries, Hayward in the north and Wilson in the southwestern part of Wisconsin States respectively, and equilibrated with 0.01 M Ca (NO3) 2 for soil solution Zn and Mn (solu-Zn and Mn), with 0.01 M Ca (NO3) 2 + 0.005 M EDTA for soil adsorbed Zn and Mn of soil Zn and Mn (b-Zn and Mn) was obtained from the ratio of ad-Zn and Mn to the solu-Zn and Mn. The concerned traces in pine seedling needles (ndls), stems (sts) and roots The results obtained show that: About 60% of solu- and ad-Zn ranged from 0.2 to 0.4 and from 1 to 2 μ / g soil respectively. About 70% of b-Zn was within 3-10. The highest content of solu-Zn compared with the lowest showed a discrepancy of more than 10-fold. The two forms of soil Zn were commonly higher in Wilson than in Hayward Nursery. About 80% of solu-, ad- and b-Mn were within 3-10, 5-5.8 μg / g soil an d 1-2 respectively