The term “Rainbow Poplar” does not refer to a separate wood species, but rather, is a designation of Yellow Poplar (Liriodendron tulipifera) that has been mineral stained. The resulting mineral stained wood—which, although not necessarily common, is by no means rare or scarce—exhibits a variety of colors ranging from green, purple, black, red, etc. It is this distinct variety of colors that turns an otherwise oridnary piece of Poplar into the intriguing Rainbow Poplar. The precise cause of these streaks and discolored wood produced in certain trees is not fully understood.See the page on regular Poplar for more information on mechanical and working characteristics of the wood.A special thanks to Mike Leigher for providing the wood sample of this wood species.
Rainbow Poplar (sanded)

Rainbow Poplar (sanded)

Rainbow Poplar (sealed)

Rainbow Poplar (sealed)

Rainbow Poplar (endgrain)

Rainbow Poplar (endgrain)

  • David Chambers

    Not being in any way a wood expert (just a DIY guy), I think I have an excellent theory about how Yellow Poplar becomes “mineral” stained: I recently purchased a long 8/4 Poplar board, well over a foot wide, for a project. It was definitely rainbowed from one end. Every color, almost just like what Mike pictured for us, but even more colors: yellow, blonde, dark brown, very dark brown, burgundy, purple and green. That tree had been struck by lightning, as evidenced by the three-foot split from that same end of my board, where both sides of the split between were heavily charcoaled (burned to a black crisp). All those colors down along and across that board were very obviously associated with the lightning strike. This coloration is definitely the result of high voltage “damage,” and one can see that the coloration changes downward from the area of the strike, from the darkest brown to finally the yellows, depending very evidently on the dissipation of the voltage down through the tree. Put that evidence together with the fact that Poplar are among the tallest of trees, that would naturally, of course, draw lightning strikes more often than other species. So, there’s my earth-shaking theory. At the time, my woodworking
    project for this board was pressing, and I did not think to photograph the proof of this theory before cutting it all up. But I have retained the charcoaled split to show people how my project included Poplar that had been struck by lightning. I would like to see some comments from foresters or other bona fide experts on this theory. If this turns out to be right, and nobody ever came up with that explanation before, I would like this explanation named after me :-). If this is correct, one could run thousands
    of volts through any live non-dried Poplar, and get Rainbow, it appears, and I would become famous for thinking of it first, right?