Blade Karst Forest

Blade Karst Forest is an original illustration set in Western Madagascar Karst. It lies in the tropics, where the climate is tropical savanna — a pronounced dry season.

Razor-edged vertical limestone blades stand in dense ranks, separated by narrow black fissures. Needle pinnacles of varying height repeat into the distance as a continuous stone forest. Small dry deciduous shrubs push out of the cracks, and one deep narrow chasm splits the plateau.

Why does limestone weather into a forest of blades?

Limestone dissolves in slightly acid rainwater, and where the rock is jointed and the rain is heavy but strictly seasonal, dissolution runs down the joints and leaves blades between them. The blades are knife-sharp because the rock is hard and the process is chemical, not abrasive. Deciduous shrubs that drop their leaves say a pronounced dry season — tropical, but with months of no rain.

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