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                               TABLE IV
              Averae PlantAi      Growth of whit., Norway, and
                         Scotd Pine in Wisconain
             White Pine          Norway Pine          Scoteb Pine
         Approx.  Average    Approx.              Approx.
         range in   total    range in  AveraIgAveag
  Total  hLt gr.   height     hit. gr.      l                 towI Aerg
  age   per year  growth     per year    Fet      pryer      Fe
  Years   Inchee    Feet      Ic.
    1    1.0- 5.5     .21      1- 6       .24       1- 6       .24
    2    2.0- 8.0     .61      1- 7       .58       1- 7       .56
    a    8.0- 9.0    1.10      8- 9       1.09      3- 9      1.07
    4    6.0-12.0    1.86      5-11       1.77      5-11       .42
    5    4.0-10.0    2.47      5-11       2.43      6-12      2.48
    6    4.0-10.0    3.22      5-11       3.07      7-13      3.35
    7    9.0-15.0    4.10     10-16       4.12      9-15      4.40
    8   11.0-17.0    5.27     12-18       5.87     1o-l       5.53
    9   15.0-21.0    6.75     12-18       6.63     13-19      6.88
    10   19.0-25.0.   5.55     14-20      8.06      15-21      8.37-
    11   18.0-24.0   10.32     17-23      9.71      15-21      9.89
    12   18.0-24.0   12.12     16-22     11.32      14-20     11.35
    1s   17.0-23.0   13.78     18-24      13.08     16-22     12.92
    14   17.0-23 0   15.46     19-25      14.91     16-22     14.53
    15   17.0-23.0   17.17     18-24      16.66     17-23     16.16
    16   13.0-19.0   18.54     18-24     18.42      17-23     17.82
    17   13.0-19.0   19.89     16-22     20.02      18-24     19.53
    18   12.0-18.0   21.14     15-21      21.56     18-24     21.27
    19   12.0-18.0   22.43     18-24'     23.32     13-24     23.04
    20   11.0-17.0   23.60     22-28      25.41     17-23     24.71
    21   12.0-18.0   24.85     21-27      27.41*    12-18     25.96
    22                         21-27      29.410
    23                         18-24      31.16*
  *Average for one plantation only.
  The foregoing     table indicates that the period        of active height
growth for young white pine plantations in Wisconsin commences
about the tenth year. Norway pine appears to begin its period of
rapid growth about its eleventh year. Scotch pine seems to increase
more uniformly in height growth every year than the others, reach-
ing a fairly stable rate aboit the nineteenth year.
Diameter Growth
  Density of the plantation and quality of soil are importint factors
in affecting diameter growth. The greater the number of trees present
the smaller the diameter, and the more the height growth is forced at
expense of diameter growth. Even on the poorestplainfeld sand good
diameter growth is found when the stand is not planted too densely.
However, the influence of soil and other site factors on diameter
growth can be seen in the white pine plantation at Nelson Dewey
State Park. Here there is a closely planted stand growing in a space
which averages about 22 square feet to the tree on a silt loam soil.
This plantation has not been attacked by the weevil. Because of this
and its greater density, its height growth is considerably above the
average. The average diameter of this 16 year old stand is 4.1 inches,
which is .6 of an inch above the average for all observed plantations
of white pine in Wisconsin at this age. This favorable height growth
and diameter must be largely attributed to the soiL.
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