What are strawberry bombs? Like in reference to strawberry fields forever?

I've read a lot about "Across The Universe" %26amp; saw the scene set to that song but i don't know a lot about the Vietnam War in general so what do "strawberry bombs" mean? I can't find a note of it in encyclopedias so i'm guessing its a slang term or something.
What are strawberry bombs? Like in reference to strawberry fields forever?
they were talking about napalm bombs,napalm is harmless until mixed with gasoline,napalm looks ust like strawberry jam
Reply:No clue - there is no reference to even a bomb in the song.