The House of Walton is a noble family appointed by King Andre von Luis III for his services in the first mana species war. Coming from a family of farmers who were appointed as soldiers through military service, Argo Walton, the founder of this family managed to create glorious achievements.
Not because of his expertise in war and also not from the number of elves he killed but from his discovery. He managed to find a synthetic fertilizer that was able to capture the mana in the soil and accelerate the growth of plants on it.
When a mage uses a wood spell faction, plants will grow from the ground even though the land is arid. This is because the mage's spell stimulates the mana inside the plant's body even if they are dead or withered. This is what happens when Deak uses a wood spell on an avalanche-covered land.