diff --git a/.kokoro/presubmit/presubmit.cfg b/.kokoro/presubmit/presubmit.cfg
index b158096f0a..14db9152d9 100644
--- a/.kokoro/presubmit/presubmit.cfg
+++ b/.kokoro/presubmit/presubmit.cfg
@@ -1,7 +1,7 @@
 # Format: //devtools/kokoro/config/proto/build.proto
 
-# Disable system tests.
+# Only run a subset of all nox sessions
 env_vars: {
-    key: "RUN_SYSTEM_TESTS"
-    value: "false"
+    key: "NOX_SESSION"
+    value: "unit-3.8 unit-3.12 cover docs docfx"
 }
diff --git a/owlbot.py b/owlbot.py
index 3027a1a8ba..1431b630b9 100644
--- a/owlbot.py
+++ b/owlbot.py
@@ -139,6 +139,7 @@ def get_staging_dirs(
         "README.rst",
         ".github/release-please.yml",
         ".kokoro/test-samples-impl.sh",
+        ".kokoro/presubmit/presubmit.cfg",
     ],
 )