diff --git a/R/orsf_R6.R b/R/orsf_R6.R
index b8b9df9b..05cdfabf 100644
--- a/R/orsf_R6.R
+++ b/R/orsf_R6.R
@@ -194,12 +194,19 @@ ObliqueForest <- R6::R6Class(
    # the standard init() function is called. If they were specified,
    # the standard check function is called.
 
-   if(!is.null(control)){
+   # this allows someone to set control to NULL and revert
+   # to using a default control for the given forest.
+   if(is.null(control)){
+    private$user_specified$control <- FALSE
+   } else {
     self$control <- control
     private$user_specified$control <- TRUE
    }
 
-   if(!is.null(weights)){
+
+   if(is.null(weights)){
+    private$user_specified$weights <- FALSE
+   } else {
     self$weights <- weights
     private$user_specified$weights <- TRUE
    }
@@ -216,7 +223,9 @@ ObliqueForest <- R6::R6Class(
    if(!is.null(n_thread))
     self$n_thread <- n_thread
 
-   if(!is.null(mtry)){
+   if(is.null(mtry)){
+    private$user_specified$mtry <- FALSE
+   } else {
     self$mtry <- mtry
     private$user_specified$mtry <- TRUE
    }
@@ -233,7 +242,10 @@ ObliqueForest <- R6::R6Class(
    if(!is.null(leaf_min_obs))
     self$leaf_min_obs <- leaf_min_obs
 
-   if(!is.null(split_rule)){
+
+   if(is.null(split_rule)){
+    private$user_specified$split_rule <- FALSE
+   } else {
     self$split_rule <- split_rule
     private$user_specified$split_rule <- TRUE
    }
@@ -244,28 +256,37 @@ ObliqueForest <- R6::R6Class(
    if(!is.null(split_min_obs))
     self$split_min_obs <- split_min_obs
 
-   if(!is.null(split_min_stat)){
+   if(is.null(split_min_stat)){
+    private$user_specified$split_min_stat <- FALSE
+   } else {
     self$split_min_stat <- split_min_stat
     private$user_specified$split_min_stat <- TRUE
    }
 
-   if(!is.null(pred_type)){
+   if(is.null(pred_type)){
+    private$user_specified$pred_type <- FALSE
+   } else {
     self$pred_type <- pred_type
     private$user_specified$pred_type <- TRUE
    }
 
-
-   if(!is.null(oobag_pred_horizon)){
+   if(is.null(oobag_pred_horizon)){
+    private$user_specified$pred_horizon <- FALSE
+   } else {
     self$pred_horizon <- oobag_pred_horizon
     private$user_specified$pred_horizon <- TRUE
    }
 
-   if(!is.null(oobag_eval_every)){
-    private$user_specified$oobag_eval_every <- TRUE
+   if(is.null(oobag_eval_every)){
+    private$user_specified$oobag_eval_every <- FALSE
+   } else {
     self$oobag_eval_every <- oobag_eval_every
+    private$user_specified$oobag_eval_every <- TRUE
    }
 
-   if(!is.null(oobag_fun)){
+   if(is.null(oobag_fun)){
+    private$user_specified$oobag_eval_function <- FALSE
+   } else {
     self$oobag_eval_function <- oobag_fun
     private$user_specified$oobag_eval_function <- TRUE
    }
@@ -279,7 +300,9 @@ ObliqueForest <- R6::R6Class(
    if(!is.null(group_factors))
     self$importance_group_factors <- group_factors
 
-   if(!is.null(tree_seeds)){
+   if(is.null(tree_seeds)){
+    private$user_specified$tree_seeds <- FALSE
+   } else {
     self$tree_seeds <- tree_seeds
     private$user_specified$tree_seeds <- TRUE
    }
diff --git a/tests/testthat/test-orsf_update.R b/tests/testthat/test-orsf_update.R
index ac2991a7..42115edd 100644
--- a/tests/testthat/test-orsf_update.R
+++ b/tests/testthat/test-orsf_update.R
@@ -77,3 +77,19 @@ test_that(
 
  }
 )
+
+test_that(
+ desc = "setting a default null field to null reverts that field to the default value",
+ code = {
+
+  fit_control <- fit_standard_penguin_bills$custom
+
+  fit_control_null <- orsf_update(fit_control, control = NULL)
+
+  expect_equal_leaf_summary(fit_standard_penguin_bills$fast,
+                            fit_control_null)
+
+ }
+)
+
+