Submitted to: International Journal of Forest Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2005
Publication Date: 12/31/2005
Citation: Veal, M.W., Taylor, S.E., Rummer, R.B., Raper, R.L. 2005. Plow power requirements for forestry site preparation. International Journal of Forest Engineering. 16(2):129-136. Interpretive Summary: Deep tillage is often used to remove the root-limiting condition of soil compaction before planting trees. However, disrupting compacted soil profiles requires large amounts of energy (fuel). A study was conducted to compare several methods of loosening the compacted soil layer prior to tree planting. Results indicated that significant energy savings were associated with using a coulter ahead of a shank commonly used for tillage. Further experiments should be conducted to determine if equivalent tree growth results from this energy efficient operation.
Technical Abstract: In this field study, data were collected to determine power requirements required by a trailing site preparation plow and the magnitudes of dynamic forces experienced by a plow during normal operation and during impact with stumps or other obstructions. Drawbar pull data were collected from five different tillage treatments on a recently harvested loblolly pine (Pinus taeda) site in central Alabama. The five treatments were: 1) a coulter, ripping shank, and four bedding disks; 2) a coulter, ripping shank, and two bedding disks; 3) a coulter and ripping shank; 4) a coulter alone; and 5) a ripping shank alone. A 330 kN [75 000 lb] capacity tension load cell was used to measure the drawbar load, a GPS receiver recorded tractor speed, four direct current displacement transducers (DCDT’s) monitored the depth of the disks, and two optical tachometers measured the speed of the tractor’s front and rear drive shafts. Each treatment produced significantly different drawbar loads (to alpha levels less than 0.001). The resulting mean loads were 46.0 kN [10 300 lb], 33.5 kN [7530 lb], 31.5 kN [7080 lb], 15.8 kN [3560 lb], and 43.4 kN [9760 lb] for treatments one through five, respectively. Maximum recorded drawbar load during a collision with a stump was 338.9 kN [76 188 lb].