Here's a good pdf regarding the potential acidity/basicity of pine needles, looks like the guy did his homework. I hope it's ok to post a link.
2008 F-350 Super Duty Dually gas guzzler
14x7 landscaping trailer
12x6 P&T hydro dump trailer w/leaf box
We run Gravely ZTRs, Honda 21"s, Kawasaki trimmers, Redmax Backpacks, LittleWonder loader