This tab is used to specify the level of genetic selection, establishment silviculture, HWC (herbaceous weed control), fertilizer rates and timing, and woody competition control in pine plantations only.
Possible levels of genetic selection range from 1st generation selections to mass control pollinated families. The level of genetic selection changes site index by -1% to +4% compared to base site index. (Note: “generation” is not a good indicator of family performance.). Earlier versions of GML allowed product allocations to be varied by level of selection. This feature has been deactivated in GML 1.2.8, but can be reactivated on request. A less arbitrary method is being developed to account for differences in product allocation by level of selection.
| Generation |
Relative Family Performance
|
SI Adjustment (%) |
|
| 1 |
Below average |
-1 |
| 1.5 (default) |
Average |
0 |
| 2 |
Good |
+1 |
| 2.5 |
Very good |
+2 |
| 3 |
Outstanding |
+3 |
| MCP |
Elite |
+4 |
Similarly, “Apply fertilizer(s) at time of planting” must be checked in order to simulate fertilization at time of planting. For loblolly pine, specify whether or not nitrogen (N) is applied with phosphorus. Time of planting fertilization treatments do not affect the growth of slash pine.“Apply HWC” must be checked in order to simulate HWC treatments. The growth response of loblolly pine to HWC treatments is different for broadleaf weeds and grass competition. Grass competition should be checked as appropriate.
“Apply fertilizer(s) at Age” must be checked and treatment age (3 to 10 years) must be specified in order to simulate juvenile fertilization. For loblolly pine, growth response to juvenile fertilization varies by nitrogen (N) rate. Nitrogen (N) rate does not affect the growth response of slash pine to juvenile fertilization; therefore, any rate can be selected.
“Apply release at Age” must be checked and the treatment age (6 years and older) must be specified in order to simulate competition control treatments. The growth of loblolly is affected by both woody competition control and mid-rotation brush control treatments. However, slash pine is affected only by woody competition control treatments.
Silvicultural treatments and physiographic regions that affect growth of planted pines
| Treatment Type |
Treatment(s) |
Loblolly
Pine |
Slash
Pine |
Longleaf
Pine |
| Establishment Silviculture |
Chemical site prep
Bedding
Tillage |
All
LCP
UCP |
No
All
No |
All
No
No |
| Herbaceous Weed Control (HWC) |
Banded
Broadcast |
All
All |
All
No |
All
All |
| Time of Planting Fertilization |
N + P fertilizers
P fertilizer only |
All
All |
No
No |
No
No |
| Juvenile Fertilization
(age required) |
100-200 lbs N + P
200-300 lbs N + P
P fertilizer only |
All
All
All |
All
No
No |
All
All
All |
| Competition Control (age required) |
Woody release
Mid-rotation brush |
UCP
LCP |
All
No |
No
No |
LCP=Lower Coastal Plain only, UCP=Upper Coastal Plain only