Arborealis Pyro was a dry arboreal planet in the Arbol system.
Large fire resistant inedible mushrooms grow on the trees here, and are used as dwellings by the native Fulgoridians (large, Moth-like, sentient creatures). The bark on the planet's tree's are fire and plasma resistant, but their interiors are highly flammable due to a high concentration of fuel absorbed by the trees from the soil. The adult trees release sap every 500 years, resulting in devastating forest fires. Fortunately, the planet's ecosystem has adapted to these conditions.
Arborealis Pyro was the site of several battles during the Clone Wars. The first was a failed attempt by the Fulgoridians to repel the Droid Army of the Separatists. The second began the Arborealis Pyro Campaign, in which the Republic sought to drive the separatists off the planet. The last battle fought on the planet during the Clone Wars ended shortly after Order 66 was executed. The Republic's outpost on the planet was destroyed seconds after the order was given by Palpatine, killing Commander Arnold before he could relay the order to his forces.
The planet was set ablaze prematurely by the Venator-class Star Destroyer the Holocaust, in attempt to silence the Fulgoridians (a wise people that showed the potential to hinder the Empire's complete rule) shortly following order 66. The bombardment devastated most of the planet's surface; the planet's ecology never fully recovered.