diff --git a/NEWS.md b/NEWS.md
index 70f698d6..7b212061 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -6,6 +6,8 @@
 
 `enhanced` - Sampling Vignette - Added content about `sample_existing()`
 
+`fixed` - `strat_map()` - Fixed improper use of `terra::hasValues`. From Robert Hijmans #31
+
 # sgsR 1.4.1
 
 `fixed` - `sample_ahels()` - gave an erroneous error when `matrices` was provided and `nQuant` did not match. Changed to allow only `matrices` to be provided.
diff --git a/R/strat_map.R b/R/strat_map.R
index 7a86c62a..35bf7ecb 100644
--- a/R/strat_map.R
+++ b/R/strat_map.R
@@ -116,7 +116,7 @@ strat_map <- function(sraster,
   }
 
   #--- error handling for raster inputs ---#
-  if (isFALSE(sraster@ptr$hasValues)) {
+  if (isFALSE(terra::hasValues(sraster))) {
     stop("'sraster' has no values.", call. = FALSE)
   }