diff --git a/env/src/lib.rs b/env/src/lib.rs
index c0cd223..d712625 100644
--- a/env/src/lib.rs
+++ b/env/src/lib.rs
@@ -73,9 +73,10 @@
 //! ## Enabling logging
 //!
 //! Log levels are controlled on a per-module basis, and by default all logging
-//! is disabled. Logging is controlled via the `RUST_LOG` environment variable.
-//! The value of this environment variable is a comma-separated list of logging
-//! directives. A logging directive is of the form:
+//! is disabled except for `error!`. Logging is controlled via the `RUST_LOG`
+//! environment variable. The value of this environment variable is a
+//! comma-separated list of logging directives. A logging directive is of the
+//! form:
 //!
 //! ```text
 //! path::to::module=log_level
@@ -196,7 +197,7 @@ pub fn init() -> Result<(), SetLoggerError> {
     log::set_logger(|max_level| {
         let (mut directives, filter) = match env::var("RUST_LOG") {
             Ok(spec) => parse_logging_spec(&spec),
-            Err(..) => (Vec::new(), None),
+            Err(..) => (vec![LogDirective { name: None, level: LogLevelFilter::Error }], None),
         };
 
         // Sort the provided directives by length of their name, this allows a