Finding sweetness among the trees: Cambium can provide a spring treat

A stand of lodgepole pine. Photo: Dave Powell/US Forest Service/Bugwood.org
A stand of lodgepole pine. Photo: Dave Powell/US Forest Service/Bugwood.org

Imagine a time in the Pacific Northwest before the fur traders first offered those dry, hard, brown cones of sugar as part of their trade goods. European honeybees had not yet made their way westward after introduction decades earlier in the colonies. Sweetness would have been available from dried berries and roasted roots, but by this time of year, supplies were probably carefully rationed. For a more concentrated shot of springtime sugars, the cambium of lodgepole pines was almost universally treasured throughout our area. It still makes a fun treat to try, especially if you have some lodgepole pine on your property in need of thinning where removing the bark from a few trees will speed the process along.

(Warning: Harvesting cambium will scar the trunk of your tree. Since cambium is a living layer just under the bark, taking large amounts exposes this living layer and may leave the tree vulnerable to weather and disease. And please don’t harvest from pine trees on tribal or public lands, such as state trust lands, or from trees on private property without permission.)

Here’s how to harvest cambium 

The usual technique to harvest cambium is to peel off and discard a vertical strip of bark and then use a scraper to remove the cambium from the exposed wood on the tree. Traditional tools for scraping were crafted from antlers or bones, but a pocket knife works fine. We have successfully used table knifes when doing this activity with kids. The goal is to scrape off a long, fleshy ribbon, a little like a thick strip of scotch tape.

Timing is everything. The cambium is at its sweet, succulent prime about the time when new needles are growing and the pollen cones are ripe. Too soon, and the sap will not be running and cambium will be thin and dry. Too late, and it will stick to the bark when you peel it off (although you can still scrape it from the inside of the bark). The perfect time is when a tap on a branch releases a cloud of pollen.

Many tribes used ponderosa pine as well and some preferred it to lodgepole. In some places, scars on the trees are still visible from this use. Carol Mack, a Washington State university Extension forester in Pen Oreille County, says she’s conducted taste tests of both species. Lodgepole is usually the winner, but she suspects that her timing was off on the ponderosa, which typically is ready several weeks earlier than lodgepole pine. Vigor and moisture availability also have a large effect on flavor and yield — porcupines are known to revisit trees to harvest the cambium from below old scars, which supposedly block the sap flow from the roots and create sugar concentrations.

The slightly resinous sweet taste of pine cambium is fun to try, and tasting it probably gives some insight into the life and diet of a bark beetle. It also sets a person to thinking how much work it used to take for a taste of “sweet,” before these days of 25-pound sacks of refined sugar at every store. How many hours of cambium harvesting would be needed to supply the several tablespoons of sugar in a single bottle of pop? In this day and age where some form of sugar seems to shows up in about everything we eat, we can thank the pine trees for giving us a glimpse of a very different (and probably healthier) world.

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(Thanks to Carol Mack, WSU Extension, Pend Oreille County, for this article.)