Plaque-bark Tree is tall tree with a massive trunk, rough bark and twisted boughs that makes up the majority of large plants in the Pocket Forests of Darwin IV, as well as being the largest plant on the whole planet.

Plaque-bark trees are usually found making up the majority of flora in the pocket forests. Often heard in the pocket forests are the delicate xylophone tones of thousands of striker-nuts, the bell-like seeds of the plaque-bark tree. Each of these is formed with two small bark strikers that beat upon its shell, eventually loosening the nut and sending it to the forest floor. The sound of these nuts is like some beautiful arboreal symphony.

Many other organisms live in and/or on the trees. These include jetdarters, hook-tailed flyers, floatballs, trunk-suckers (which feed on the sap), and daggerwrists.

At times, groves of young plaque-bark trees can be seen growing out of a keeled grove-back's dorsal carapace. At first this was speculated that this might be some kind of protective adaptation that enables it to hide; this seems unlikely, though, given the creature's bulk. It was later learned that once the keeled grove-back reaches this size and age it has no true enemies and does not fear predation.

The trees on a grove-back's back crack and rustle with each ponderous, lurching footfall, while the enormous skid turns the ground with a clatter of upturned boulders. The noise of the animal's passage is substantial.

Grove-Back study

A newly-emerged grove-back with an arrowtongue at its feet, feeding opportunistically on the prey flushed by the grove-back's movement. Most of the trees on the grove-back's carapace will die within a few months, but their trunks will remain standing for years to come.

A nesting grove-back will be submerged in a pit and grown over with underbrush and small trees. It looks like nothing more than a small, tree-covered hill. Based on the growth of the trees, it is estimated that the animal has been buried and immobile for at least 10 years. It turns out that the animal is hibernating. During the course of its prolonged stasis, smaller creatures, as well as plants, accumulate on the behemoth's porous dorsal shell. Five days after laying its eggs, the keeled grove-back rises shakily amidst a great cloud of debris and soil. Its stiffened legs, trembling under the immense, forgotten weight, tentatively take their first steps in more than 10 years. The tangled forest on the creature's back shakes like reeds in the wind as it moves forward. The trees will soon die now that the Grove-back is awakened and walking, but this is also an efficient way to spread their seeds.