It doesn't seem like it would be that hard to find a needle in a haystack if you were really persistent , amirite?

It'd be easy. Just light the hay on fire.

Mythbusters!

I think it depends on the size of the hay and the type of needle.

If it's a decent-sized pile of hay and the needle is metal, you shouldn't have a tough time finding the needle with just a bit of time and a strong magnet.

Magnets!