The Wooden Spaceships. Land and Overland Book 2

Twenty-four years have passed since Toller Maraquine led the population of Land to the sister planet of Overland. Somehow, those left behind have become immune to the deadly pterthacosis which caused the exodus, and their voracious ruler now lays claim to Overland. Grudgingly put in charge of his planet's defence, Toller designs a front-line force of spaceships and satellites made of wood, which will engage the enemy fleet in the cold vastness of space, before the invaders can set food upon Overland.
As the war proceeds, a far more deadly, alien menace makes itself known, which will threaten the entire existence of Overland.