Problem totally killing a particle system

Snowbat

L4: Comfortable Member
Apr 23, 2013
165
74
So, I have a nuclear bomb detonation on my map and it creates a particle system mushroom cloud. The "cap" of the cloud is a bunch of smoke sprites that get spawned, grow in size slowly and dissipate after X seconds. This keeps getting renewed until I kill the particle system which will stop spawning new sprites and eventually, the already existing ones will dissipate and the "cap" will die.
That's good, that's what I want.

The problem is the "stem" of the cloud. This is a particle system that creates a set amount of smoke sprites and these never fade out and never get regenerated. They just stay there.
When I kill this particle system, the stem stays. I guess it's because killing a particle system doesn't actually remove the spawned sprites but merely stops the system from spawning them, letting the existing ones dissipate.
Thing is, the stem's sprites just spawn once and then stay. Killing this system doesn't remove the existing sprites unfortunately.

Anyone knows how to still force those fucking sprites to be removed?