In mid-July 1970, the 7th Marine Regiment began planning for an incursion into the People's Army of Vietnam Base Areas 112 and 127 in the mountain ranges of Quảng Nam Province. Since January more than 250 patrols into these 2 areas had killed more than 300 PAVN. The Pickens Forest tactical area of responsibility would be in the southeast of Base Area 112, 14.5km southwest of An Hoa Combat Base and centred on the Thu Bồn River. The area was believed to house the Front 4 Headquarters, headquarters and supply units of the Viet Cong 1st Regiment and the PAVN 38th Regiment and the 490th Sapper Battalion.
Operation
The operation began on the morning of 16 July when helicopters from Marine Aircraft Group 16 landed Company C, 1st Battalion, 5th Marines at Firebase Defiant followed by Battery G 3rd Battalion, 11th Marines and the 7th Marine Regiment command group. Company B 1/5 Marines was landed at Landing Zone Bluejay and Company E, 2nd Battalion, 7th Marines was landed at Landing Zone Starling on each side of the Thu Bồn River, north and south of Firebase Defiant. At 09:30 the 1st Battalion, 7th Marines command group, Companies C and D and 4 mortars from Battery W 3/11 Marines landed at Firebase Mace, while the 2/7 Marines command group and 4 mortars from Battery W 3/11 Marines landed at Firebase Dart and Companies F and G landed at Landing Zone Robin. Over the next 10 days the infantry units at Firebases Dart and Mace swept east towards the blocking forces at the bases along the Thu Bồn River, however the PAVN/VC generally avoided contact, harassing the Marines with grenades and sniper fire. On 22 July the mortar battery and 1/7 Marines command group at Firebase Mace moved to Hill 110, north of Firebase Defiant to cover the infantry advance and on 23 July the mortar battery at Firebase Dart moved to Firebase Defiant. On 26 July the 1/7 Marines command group and Company B returned to Landing Zone Baldy. On the night of 26 July Company E, 2/7 Marines ambushed a 30-strong PAVN unit, a sweep of the area the next day found 5 dead PAVN, 3 weapons and 24 abandoned packs. On 27 July a VC defector revealed a weapons cache to Company E, 2/7 Marines containing 139 SKS rifles. That day Company C 1/7 Marines returned to LZ Baldy, while Company H, 2/7 Marines joined the operation. Four howitzers and the artillery command group at Firebase Defiant moved to Firebase Ross and the remaining 2 howitzers moved to Hill 110 forming a provisional artillery batter with the mortars there. On 28 July 1/5 Marines left the operation and returned to Hill 327 and the 7th Marine Regiment command group returned to LZ Baldy, leaving the 2/7 Marines responsible for the Pickens Forest TAOR. On 30 July as 8 Company E, 2/7 Marines searched a gorge of the Thu Bồn River in 2 small boats they were fired on by 4 PAVN/VC machine guns in caves along the river sinking both boats and killing 2 Marines. The rest of the company provided covering fire while Marine jets dropped Napalm which suppressed the machine guns. Company C, 1/5 Marines was landed by helicopter south of the ambush site that afternoon to block any exit route and the next day moved forward to the ambush site killing 1 VC. On 9 August 2/7 Marines was ordered to expand its operations further west and that day Company E and two 105mm howitzers from Firebase Ross were landed at the former Vietnamese Marines Firebase Hatchet, 32km northwest of Hill 110, their arrival was met by 5 122mm rockets which killed one South Vietnamese soldier. On 10 August 2 105mm and 2 155mm howitzers were flown in from Firebase Ross followed by the 2/7 Marines command group and then on 12 August Companies E and F arrived at the base and began searching the surrounding area. On 16 August Company G and the provisional artillery battery at Hill 110 moved back to LZ Baldy. On the morning of 20 August the 3rd Platoon of Company H was sweeping an area near the hamlet of My Hiep, 3km north of Hatchet when it was ambushed by a PAVN unit, Company F marched to the scene while Company G was flown in from LZ Baldy but the PAVN withdrew by 13:00 leaving 3 dead, while the Marines had lost 1 killed. A sweep of the area the next morning found another 1 PAVN dead and 12 bunkers. On 22 August a further 6 bunkers were found nearby and intelligence determined that this was the headquarters of part of the PAVN 38th Regiment which was preparing to attack Hatchet. On 23 August 4 PAVN were seen scouting the Hatchet perimeter and were fired on using a 106mm recoilless rifle. On 24 August the Marines at Firebase Hatchet were withdrawn and returned to their parent units, with the 2/7 Marines immediately being deployed into the Quế Sơn mountains as part of Operation Ripley Center.
Aftermath
Operation Pickens Forest concluded on 24 August, the Marines had lost 4 killed and the PAVN/VC 99 killed.
