SA93_38.HTML

 

Explanation of SA93_38.dat

 

 

Documentation for Pine Growth Ring Data

 

On March 2, 1993, 38 loblolly pine trees were felled representing various combinations of the thinning and pruning treatments.

 

After the trees were felled, approximately a 2"-thick disk was cut at the marked DBH.  Three disks were cut from the base of three separate limbs in the crown.  Each disk was identified with the tree number (and plot number if necessary) and each limb disk was also numbered according to its respective height (1=lowest, 2 = middle, 3=highest).  All disks were allowed to air dry and smoothed using a large electric sander to increase visibility of rings.  The limb disks were cut into smaller pieces for easier handling using a band saw.

 

Four radii were drawn on each disk.  Defected areas and unusually short or long sides were avoided when drawing the lines.  Numbers were assigned for all lines on each disk. Measurement equipment consisted of a millimeter scale standard ruler and a WILD TYP 355110 microscope with a lens magnification of 10x.  The microscope was calibrated using a scale provided by Dr.  Lynne Thompson.  Calibration was verified each morning and afternoon before starting measurements to be sure the adjustment had not been changed.  

 

Measurements began at the outer edge at year 35 and were made to the nearest whole millimeter.  The width of each late-wood ring and the total width of each annual ring were measured along each of the four radii.  Water was occasionally applied to the surface of disks when lines were hard to see.  Sometimes hard-to-see rings had to be penciled in using an estimation of the ring width from another location.  If all rings could not be seen clearly on a radius, a new radius was drawn and counted.  In some cases asymmetrical growth and abnormal rings in the limbs allowed only two or three radii to be measured rather than four.  Data for incomplete radii were assigned to missing.  Individual ring measurements were made to the nearest 0.1 millimeter.  If the late-wood or the total width of the ring was too thin to measure (less than 0.1mm), then total width was recorded as 0.1 and late-wood was recorded as missing or 0.1.  Annual ring widths were summed.  This sum was then checked against a single measurement of the radius with a ruler along the same line.  If a difference greater than plus or minus 1.5mm was found in the stems or 0.5mm in the limbs, then growth rings were remeasured.  It was also verified that all radii on a particular stem or limb contained the same number of annual rings.   Random rechecks were conducted on the stem discs to control error.  These rechecks did not reveal any significant errors. 

 

            Measurements began on April 7, 1993 and were completed on June 6, 1993.  All measurements were conducted by Arnulfo Zendejas, Steven Tompkins, Jimmy Fowler and Sarah Kluender.  Suzanne Wiley supervised this work and created the data file which includes 1254 observations and 35 variables:

 

                                                                             


Stem data

1. Plot number.

2. Tree number.

3. Age of ring.

 

                          Stem rings

4. Width of late wood ring for the first radius.

5. Total width of ring for the first radius.

6-7. The last two variables (late wood and total) for the second radius.

8-9.  Late wood and total widths for the third radius.

10-11. The same variables (late wood and total) for the fourth radius.

 

                         Branch rings

12-13. Late wood and total widths for the first radius of the first branch.

14-15. Late wood and total widths for the second radius of the first branch.

16-17. Late wood and total widths for the third radius of the first branch.

18-19. Late wood and total widths for the fourth radius of the first branch.

 

20-21. Late wood and total widths for the first radius of the second branch.

22-23. Late wood and total widths for the second radius of the second branch.

24-25. Late wood and total widths for the third radius of the second branch.

26-27. Late wood and total widths for the fourth radius of the second branch.

 

28-29. Late wood and total widths for the first radius of the third branch.

30-31. Late wood and total widths for the second radius of the third branch.

32-33. Late wood and total widths for the third radius of the third branch.

34-35. Late wood and total widths for the fourth radius of the third branch.

 

 

All radii widths are in millimeters.


 

TREE INFORMATION:


 

Plot Tree Den Prune DBH Height

 1 107 50 55 18.1 81.9

 3 285 90 40 16.0 83.7

 4 395 90 25  9.6 69.4

 6 115 30 55 20.7 76.9

 7 277 50 25 17.6 76.5

 8  15 70 55 14.2 79.4

 8 497 70 55 15.8 77.9

 9 435 90 55 14.8 80.2

11  73 70 40 15.1 80.4

12 323 70 25 16.3 80.3

13  33 90 40 14.5 81.5

13  63 90 40 13.5 69.6

14 207 50 55 15.4 75.1

16 295 70 40 15.9 74.6

19 279 90  . 14.3 79.5

19 291 90  . 13.1 76.9

21  58 50 40 17.6 77.0

22 222 50 25 16.4 82.3

23 409 90 25 14.4 80.4

26  17 70 40 14.3 74.9

27 241 30  . 20.9 72.6

28   5 50 55 19.7 78.5

29 109 90 55 13.6 74.4

29 110 90 55 13.5 73.3

30 155 50 40 16.5 82.0

31 323 70 55 16.6 76.0

32 355 30 40 20.3 74.5

33 129 30 55 20.0 74.2

36 215 70 55 16.1 82.1

37 448 90 55 12.9 76.6

37 488 90 55 12.9 80.1

37 489 90 55 12.9 80.8

38 154 90 40 10.1 65.4

38 166 90 40 11.3 76.3

38 168 90 40  8.9 58.7

39 330 70 25 15.0 74.8

39 331 70 25 14.5 78.9

40  93 70  . 16.2 84.0