Pine and spruce is good, hemlock i find is better (not to be confused with hemlock plant) and I've found that larch is quite poor.
Hemlock has been known to be confused with yew which is poisonous, a couple of differences
Hemlocks leaves are irregular lengths where as yew have regular lengths, hemlock has cones and yew has red berries and hemlock grows usually straight whereas yew is quite gnarly.
Also I've heard of gorse being used as a tea to but haven't tried it myself.
Thanks for the article,
Ste