found leaves on top of cabin air filter when I removed old filter

[Ralph Baudendistel]

removed old cabin air filter found allot of old leaves on top of it how can they get there

[CamGTP]

Pretty sure it grabs air from the cowl.

[Black02Silverado]

They come in the same way the air comes in.  That is why the filter is there to protect the HVAC system.  Most don't even know they have a cabin filter.  I got a K&N cabin filter and clean it out once a year.  Saves me from buying one and it will last a long time.  Plus the filtration isn't as important like it is for the engine.