The 27th Surveyors are part of the ground units on the death world Pholos IV. They remove invasive vegetation from settlements, patrol for xenos incursion, and quell uprisings among the rowdy recolonists.
The deep green robes with shocking yellow lining mirror the vegetation that sprouts, grows tall, and flowers often in the same day. The temperate latitudes pulse with these colors when viewed from space.
The surveying contingent can rely on support from giant machines. Knights with claws and saws for felling overnight forests, Onagers specially modified to traverse the decaying swamps thick with fungal rot, resurface roads thick with cracks only weeks after being layed down, and pulp the lignin and experimental protein bioheresy into specialized oils and unguents. The ruin wrought by the mad Biologis would be turned to the might of the Mechanicum at last.