The kou tree was so useful to early Hawaiians, and is so widely spread throughout Polynesia, that it made perfect sense for early scientists to assume it was one of the "canoe plants."

Those are plants Polynesians are assumed to have brought with them in canoes — the plants that they deemed critical to survival in a new land. Canoe plants included food plants, medicinal ones, and ones used for decorative purposes, cordage and more. Most of the nearly 30 canoe plants are found throughout the Polynesian Triangle.

Kou is perhaps most valuable for its wood, which can be carved into sturdy, long-lasting bowls that can hold liquid foods without imparting a taste to them. In addition, its orange flowers were used for lei, and its leaves could be used to dye tapa, as Isabella Abbott wrote in her remarkable book "La'au Hawai'i: Traditional Hawaiian Uses of Plants."

Other canoe plants were yams, sweet potatoes, gingers, bananas, breadfruit, coconut and many more.

It had long been believed the pandanus, hala, was a canoe plant, for the food value in its fruit, but perhaps more for the prized leaves used for weaving mats, sails and much more. But some years ago, hala imprints were found in an ancient lava flow, proving the plants predated human presence in the Islands. More recently, hala pollen has been found deep in sediment layers at multiple sites that date to long before human arrival, confirming the lava-flow evidence.

Now, it turns out kou falls into the same category.

Pollen studies in the Makauwahi Sinkhole at Maha'ulepu on Kaua'i have found that kou was part of the coastal forest on Kaua'i thousands of years before the first Polynesians set foot on the archipelago.

Archaeologist/ecologist David Burney, who conducted the pollen studies, said the find was a surprise.

He has been trying to plant a forest that looks like what was on the southern Kaua'i coast before Hawaiians arrived, and his plantings now include both the kou and the hala.

As Abbott has suggested, this still doesn't mean the first canoes didn't carry these plants. They were important enough to have been part of the canoe plant collection.

But in these cases, the early visitors would have been confronted by something familiar amid all the strange Hawaiian plants and creatures. And they could have begun fashioning food containers from the kou and sleeping mats from the hala without waiting for their canoe-borne materials to mature and reproduce.

If you have a question or concern about the Hawaiian environment, drop a note to Jan TenBruggencate at P.O. Box 524, Lihu'e, HI 96766 or jant@honoluluadvertiser.com. Or call him at (808) 245-3074.