Making landing areas suitable
As my fellow Vietnam vet's mention we had no qualms about making the landing zone (LZ) fit by using the rotor blades of our UH-1D's. Any smaller branches and bushes were no problem.
In the Mekong Delta there were lots of Mangrove Swamps. In order to have a clear landing area B-57's & or F-100's would drop a large bomb to clear the Mangrove's. The size of the bomb dictated the size of the clear area. The number of bombs dropped dictated the number of LZ's & helicopters that could land at the same time.
Then the biggest problem was for the troops we were dropping off. Once they departed the helicopter they were knee deep in mud, etc. To extract them later we would hover just above the mud and they would hold on to the skids. When they were ready we would slowly pull pitch and they would "pop" out of the mud like a cork in a bottle. They would then climb into the aircraft. We always felt sorry for them and what a great bunch.
I was with the 121st Soc Trang Tigers in 1968.