diff --git a/src/regolith/regolith_mix.f90 b/src/regolith/regolith_mix.f90
index 38aed0a1..ab132ae8 100644
--- a/src/regolith/regolith_mix.f90
+++ b/src/regolith/regolith_mix.f90
@@ -45,7 +45,7 @@ subroutine regolith_mix(user,surfi,mixing_depth,domain)
 
    newlayer%thickness = 0.0_DP
    newlayer%comp      = 0.0_DP
-   newlayer%age(:)    = 0.0_DP
+   newlayer%age(:)    = 0.0_SP
    allocate(newlayer%distvol(1+domain%rcnum))
    newlayer%distvol(:) = 0.0_DP
    newlayer%ejm       = 0.0_DP