Charge!

Enemy raygun fire had given away their positions on the fringes of - what Flight Lieutenant Karlssøn liked to think of as Jungle. No vessels had their footprints near their position on Marlow, so no one was bothering with asking for an orbital attack. This situation lasted for three days now, and his squad was out of robots to do the job. He knew, he had to take this opportunity, or they would have to spend next week in this crater.
Karlssøn barked his commands, and started climbing the edge of the crater, leading his remaining men out in the raygunfire-lit kill-zone.

The planet Marlow was classified uninhabitable four days later.

As the Space Patrol got dragged into more and more long term conflicts with more advanced species, trench warfare was proven one of the most efficient tactics... what tells us a lot of how lossy raygun dominated battlefields are.
Ground combat is seldom considered worth the effort, especially after bombing planets into submission. On the rare occasions it occurs, robots swarm the fields, closely followed by the armed rocketmen of the patrol.