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Friday Report

FERTILIZATION AFTER PPMC-THINNING AND ROW-THINNING

In our January issue we used PTAEDA2V to predict the typical stand that we usually establish on cultivated fields. To help us describe the impact of fertilization, here it is again at age 12 prior to thinning:

INPUTS

PREDICTED

Site Index = 80
Growing Seasons Completed = 12
Planted Trees = 363
Percent Hardwood = 0

Dominant Height = 45.3
Average DBH = 8.3
Average Height = 51.5
Average Crown Ratio = 51.6

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
3	1.8	33.8	.1	2.0	.0	.0
4	11.8	39.0	1.0	20.8	.0	.0
5	16.3	43.9	2.3	49.3	.4	.0
6	31.8	46.9	6.2	140.4	1.3	.0
7	37.2	49.7	10.0	234.4	2.3	.0
8	71.7	52.0	25.2	613.7	6.2	.0
9	61.7	53.6	27.0	674.9	7.0	.0
10	39.9	55.0	21.6	552.8	1.4	1181.2
11	26.3	55.8	17.2	444.0	.6	1211.1
12	17.2	57.2	13.3	353.6	.2	1135.2
13	.9	59.6	.8	21.5	.0	77.0
Total	316.7		124.7	3107.5	19.4	3604.4

Notice that the 10, 11, and 12 DBH classes contain both pulpwood and sawtimber trees. These trees are big enough for sawtimber, but some do not qualify because of form, defect, or disease. Please refer to the January issue for a diagram showing location, size, and quality of each tree.

Using the new fertilizer inputs in PTAEDA2V, we have predicted results of thinning by different methods. In the PPMC method, the thinning removed all poor-quality trees plus enough smaller trees to leave a residual stand of 165 per acre. In the Row method, the thinning removed every fourth row plus all poor-quality trees plus enough smaller trees to leave 165 per acre. For both methods, here are the thinnings, the stands fertilized after thinning, and the final harvests:

PPMC Thinning

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 12 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 45.3 Average DBH = 6.9 Average Height = 48.6 Average Crown Ratio = 47.4

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
3	1.8	33.8	.1	2.0	.0	.0
4	11.8	39.0	1.0	20.8	.0	.0
5	16.3	43.9	2.3	49.3	.4	.0
6	31.8	46.9	6.2	140.4	1.3	.0
7	37.2	49.7	10.0	234.4	2.3	.0
8	26.3	51.9	8.9	216.9	2.2	.0
9	11.8	53.5	5.1	127.2	1.3	.0
10	10.0	54.1	5.3	132.6	1.4	.0
11	3.6	55.5	2.3	58.9	.6	.0
12	.9	59.5	.7	20.2	.2	.0
Total	151.6		41.9	1002.6	9.7	.0

The stand to be carried to harvest at age 22 is as follows:

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 12 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 45.3 Average DBH = 9.5 Average Height = 54.2 Average Crown Ratio = 55.4

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
6	.0	.0	.0	.0	.0	.0
7	.0	.0	.0	.0	.0	.0
8	45.4	52.0	16.3	396.8	4.0	.0
9	49.9	53.6	21.9	547.7	5.7	.0
10	29.9	55.4	16.3	420.2	.0	1181.2
11	22.7	55.9	14.9	385.1	.0	1211.1
12	16.3	57.1	12.6	333.4	.0	1135.2
13	.9	59.6	.8	21.5	.0	77.0
Total	165.2		82.8	2104.8	9.7	3604.4

Note that these trees are much larger and taller and have larger crowns than those removed in the thinning.

Predicted stand in the PPMC harvest at age 22 is as follows:

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 22 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 73.9 Average DBH = 13.1 Average Height = 85.0 Average Crown Ratio = 38.6

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
9	.0	.0	.0	.0	.0	.0
10	4.5	76.0	2.5	88.1	.0	294.3
11	29.0	81.3	19.7	738.8	.0	2696.9
12	41.7	84.0	33.2	1285.1	.0	4903.3
13	29.0	86.5	26.9	1071.0	.0	4218.2
14	20.9	86.0	22.1	875.8	.0	3511.9
15	18.1	87.7	22.1	892.4	.0	3641.9
16	16.3	87.8	22.5	907.1	.0	3741.7
17	4.5	90.5	6.8	285.0	.0	1186.0
18	.9	95.5	1.5	66.5	.0	279.1
Total	165.2		157.3	6209.9	.0	24473.2

Row Thinning

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 12 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 45.3 Average DBH = 7.5 Average Height = 49.7 Average Crown Ratio = 49.4

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
3	1.8	33.8	.1	2.0	.0	.0
4	11.8	39.0	1.0	20.8	.0	.0
5	16.3	43.9	2.3	49.3	.4	.0
6	27.2	46.6	5.2	116.4	1.1	.0
7	11.8	49.5	3.2	74.9	.8	.0
8	25.4	51.7	9.0	217.2	2.2	.0
9	26.3	53.7	11.5	288.0	3.0	.0
10	16.3	54.2	8.6	216.6	1.4	226.0
11	9.1	56.0	5.9	152.9	.6	298.1
12	5.4	57.8	4.2	111.3	.2	308.6
Total	151.6		50.9	1249.4	9.6	832.7

Note that, although the same number of trees would be removed, they are larger (50.9 sq.ft. of basal area versus 41.9 in the PPMC thinning) and include the sawtimber trees that were located in the rows.

The stand to be carried to harvest at age 22 is as follows:

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 12 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 45.3 Average DBH = 8.9 Average Height = 53.2 Average Crown Ratio = 53.6

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
6	4.5	48.8	1.0	24.0	.2	.0
7	25.4	49.7	6.8	159.5	1.6	.0
8	46.3	52.1	16.2	396.5	4.0	.0
9	35.4	53.5	15.5	386.9	4.0	.0
10	23.6	55.6	13.0	336.3	.0	955.2
11	17.2	55.8	11.3	291.1	.0	912.9
12	11.8	57.0	9.2	242.3	.0	826.6
13	.9	59.6	.8	21.5	.0	77.0
Total	165.2		73.8	1858.1	9.8	2771.7

Note that these trees are not much larger in DBH, height, and crown ratio than those removed in the thinning. There is little chance that the 29.9 trees per acre 6" and 7" DBH will grow to sawtimber size in ten years.

Predicted stand in the Row harvest at age 22 is as follows:

INPUTS	PREDICTED
Site Index = 80 Growing Seasons Completed = 22 Planted Trees = 363 Percent Hardwood = 0	Dominant Height = 73.9 Average DBH = 12.5 Average Height = 84.2 Average Crown Ratio = 37.3

				Total	Volume	Volume
DBH	Number	Average	Basal	Volume	Cords	Scribner
Class	Trees	Height	Area	o.b.	To 4 in.	Bd. Ft.
9	11.8	76.5	5.3	188.4	1.9	.0
10	18.1	79.8	9.9	367.0	.0	1245.2
11	31.8	81.8	21.1	797.9	.0	2902.7
12	29.9	84.7	23.9	934.5	.0	3575.3
13	23.6	85.4	21.4	843.0	.0	3303.8
14	17.2	87.2	18.4	738.6	.0	2969.0
15	15.4	87.5	18.6	749.6	.0	3055.7
16	10.9	88.3	14.9	607.5	.0	2506.6
17	6.4	92.0	9.9	419.1	.0	1749.1
Total	165.2		143.6	5645.6	1.9	21307.4

Financial Analysis

Here is how trees in the row thinning differ from those in the PPMC thinning:

1. They include some sawtimber trees in the minimum size classes rather than allowing them to grow to DBH classes with higher unit values.

2. These same sawtimber trees must be sold at lower-than-normal unit values because of the very small volume of them per acre.

3. Although 11.8 sawtimber-quality trees per acre are such poor growers that they do not become large enough in 22 years, they were allowed to occupy growing space until they were finally sold for pulpwood prices.

These figures are from an actual PPIC purchased by PPMC in Burke County, Georgia. Using identical establishment costs, landowner payments, timber-selling fees, and management costs, and evaluating thinnings and harvests with current prices in Burke County sealed-bid sales, we calculated the IRR% for each to be:

PPMC thinning method
Row thinning method
Plus for the PPMC method

11.07
10.54
00.53

Although a plus of 0.53% may not seem like much to you, it allows us to pay a landowner an extra $5.00 to $10.00 per acre per year for a PPIC and increases our chances of trading with him. We like it a lot.

The plus would be larger if the pulpwood producers cut a few too many larger trees or fail to leave 165 trees per acre to assure shading off of lower branches. PPMC believes that the typical row-thinning method is an attempt to short-cut a highly technical process, a short-cut that, by reducing expenses, reduces IRR. PPMC retains an interest in all its PPICs and earns its keep by producing high returns on invested capital. It wouldn't be caught dead using row thinnings.