Palo Verde trees, recognizable by their distinctive green bark, are a common sight in the Southwestern desert landscape. When these trees fall, homeowners often wonder if the material is suitable for burning. Palo Verde wood is generally not considered high-quality firewood, especially for indoor use, due to its low density and low heat output. Its characteristics make it better suited for specific, short-duration applications like kindling or an outdoor fire pit.
Assessing Palo Verde’s Burn Quality
Palo Verde is classified as a low-density material, typically weighing 28 to 32 pounds per cubic foot. This light, porous structure means a cord contains significantly less combustible mass than denser hardwoods like oak or mesquite. Consequently, the wood produces a low heat output, yielding only about 12 to 15 million BTUs per cord, less than half the heat energy of traditional hardwoods.
The low density results in an extremely fast burn time, making it unsuitable for sustained heat. Palo Verde combusts quickly and turns to ash rapidly, requiring constant replenishment to maintain usable heat. Burning Palo Verde often releases an unpleasant aroma, described as sour or reminiscent of rotten fruit. This pervasive odor is a major reason the wood is discouraged for use in indoor fireplaces or wood stoves.
Preparing and Seasoning the Wood
Palo Verde’s soft nature means it is exceptionally easy to split, often requiring minimal effort with an axe or splitting wedge. This characteristic is a practical benefit for processing the wood, as less dense woods are less physically demanding to prepare. The low density also contributes to a relatively short seasoning period compared to the 12 to 18 months required for most dense hardwoods.
Because the wood is naturally low in moisture when dead, it can often be fully seasoned in approximately six to eight months. Proper seasoning involves stacking the split wood off the ground in a single row with plenty of airflow, ensuring that the moisture content drops below 20 percent. If felled wood is left on the ground, its weak structure and high sap content can cause it to rot quickly.
Specific Safety Considerations
A significant safety concern when burning Palo Verde is its propensity for excessive sparking and popping. The wood’s porous internal structure holds pockets of air and residual moisture, which rapidly expand when heated. As the internal pressure builds, the rapid expulsion of hot air and steam causes the wood to splinter and launch hot embers outward.
This aggressive popping action makes Palo Verde a poor choice for open fireplaces and should be avoided in any indoor setting. Furthermore, dead Palo Verde trees are frequently infested with the larvae of the Palo Verde Borer beetle. Storing infested firewood near a home can introduce these large, wood-feeding pests to the structure or surrounding landscape.