Hey Mr. Green,

As a volunteer mountaineering instructor, I wonder about artificial logs. Participants in our winter camping trips used to carry them in for bonfires, but we discontinued this after some Internet forums criticized it. Log manufacturers say their logs burn cleaner than natural ones because they're made of waste wood. So, by the principle of "leave no trace," are fake logs better than forest wood? —Luke, in Seattle

Anybody tough enough to camp in winter shouldn't be intimidated by some random Internet forum. Fireplace logs are indeed better than wood ones because they're made of wood waste (read: sawdust), and they burn a lot cleaner. Also, they spare dead wood that hosts critters vital to the sylvan food web. 

Leave-no-tracers also favor artificial logs because real wood can contain pests like gypsy moths and emerald ash borers that devastate living trees, which is why some states ban firewood from forests more than 10 miles away. 

Before stoking up any fire, make sure that it's legal and that conditions aren't too dry or dangerous. Never burn trash or food (including the artificial log wrapper)—it can be toxic or fail to combust completely. And make sure your fire's truly out by dousing it with water until the ashes are cool to the touch.