diff --git a/bld/CLMBuildNamelist.pm b/bld/CLMBuildNamelist.pm
index 3b169159b8..faeb107e76 100755
--- a/bld/CLMBuildNamelist.pm
+++ b/bld/CLMBuildNamelist.pm
@@ -870,12 +870,13 @@ sub setup_cmdl_bgc {
   my $var = "soil_decomp_method";
   add_default($opts, $nl_flags->{'inputdata_rootdir'}, $definition, $defaults, $nl, $var,
               'phys'=>$nl_flags->{'phys'}, 'use_cn'=>$nl_flags->{'use_cn'}, 'use_fates'=>$nl_flags->{'use_fates'} );
+  my $soil_decomp_method = remove_leading_and_trailing_quotes( $nl->get_value( $var ) );
 
   if ( &value_is_true($nl_flags->{'use_cn'}) ||  &value_is_true($nl_flags->{'use_fates'}))  {
-     if ( remove_leading_and_trailing_quotes( $nl->get_value($var)) eq "None" ) {
+     if ( $soil_decomp_method eq "None" ) {
         $log->fatal_error("$var must NOT be None if use_cn or use_fates are on");
      }
-  } elsif ( remove_leading_and_trailing_quotes($nl->get_value($var)) ne "None" ) {
+  } elsif ( $soil_decomp_method ne "None" ) {
      $log->fatal_error("$var must be None if use_cn or use_fates are not");
   }
   #
@@ -885,13 +886,13 @@ sub setup_cmdl_bgc {
   my %settings = ( 'bgc_mode'=>$nl_flags->{'bgc_mode'} );
   foreach my $var ( @list ) {
      add_default($opts, $nl_flags->{'inputdata_rootdir'}, $definition, $defaults, $nl, $var,
-                 'phys'=>$nl_flags->{'phys'}, 'use_cn'=>$nl_flags->{'use_cn'}, 'use_fates'=>$nl_flags->{'use_fates'} );
+                 'phys'=>$nl_flags->{'phys'}, 'soil_decomp_method'=>$soil_decomp_method );
      $nl_flags->{$var} = $nl->get_value($var);
   }
-  if ( remove_leading_and_trailing_quotes( $nl->get_value($var)) eq "None" ) {
+  if ( $soil_decomp_method eq "None" ) {
      foreach my $var ( @list ) {
         if ( &value_is_true($nl_flags->{$var}) ) {
-           $log->fatal_error("When soil_decomp_method is NONE $var can NOT be TRUE");
+           $log->fatal_error("When soil_decomp_method is None $var can NOT be TRUE");
         }
      }
   } else {
diff --git a/bld/namelist_files/namelist_defaults_ctsm.xml b/bld/namelist_files/namelist_defaults_ctsm.xml
index 02e6860bc8..af08046656 100644
--- a/bld/namelist_files/namelist_defaults_ctsm.xml
+++ b/bld/namelist_files/namelist_defaults_ctsm.xml
@@ -2527,15 +2527,14 @@ lnd/clm2/surfdata_map/release-clm5.0.30/surfdata_ne0np4.CONUS.ne30x8_hist_78pfts
 <!-- Defaults for different BGC modes           -->
 <!-- =========================================  -->
 
-<use_lch4                              >.false.</use_lch4>
-<use_lch4           use_cn=".true."    >.true.</use_lch4>
-<use_lch4           use_fates=".true." >.false.</use_lch4>
 <soil_decomp_method use_cn=".true."    >CENTURYKoven2013</soil_decomp_method>
 <soil_decomp_method use_fates=".true." >CENTURYKoven2013</soil_decomp_method>
 <soil_decomp_method                    >None</soil_decomp_method>
-<use_nitrif_denitrif                   >.false.</use_nitrif_denitrif>
-<use_nitrif_denitrif use_cn=".true."   >.true.</use_nitrif_denitrif>
-<use_nitrif_denitrif use_fates=".true.">.false.</use_nitrif_denitrif>
+
+<use_lch4            soil_decomp_method="None" >.false.</use_lch4>
+<use_lch4                                      >.true.</use_lch4>
+<use_nitrif_denitrif soil_decomp_method="None" >.false.</use_nitrif_denitrif>
+<use_nitrif_denitrif                           >.true.</use_nitrif_denitrif>
 
 <!-- ===== FATES DEFAULTS =========== -->
 <fates_spitfire_mode           use_fates=".true.">0</fates_spitfire_mode>