diff --git a/doc/api/next_api_changes/2018-01-31-AL.rst b/doc/api/next_api_changes/2018-01-31-AL.rst
new file mode 100644
index 000000000000..ace7046efe0c
--- /dev/null
+++ b/doc/api/next_api_changes/2018-01-31-AL.rst
@@ -0,0 +1,8 @@
+Deprecations
+````````````
+
+``dates.strpdate2num`` and ``dates.bytespdate2num`` are brittle in the
+presence of locale changes, and are deprecated.  Use standard datetime
+parsers such as `time.strptime` or `dateutil.parser.parse`, and additionally
+call `matplotlib.dates.date2num` if you insist on converting to Matplotlib's
+internal datetime representation; or use ``dates.datestr2num``.
diff --git a/examples/misc/load_converter.py b/examples/misc/load_converter.py
index 2c3e03f73b89..5f0d7940f1cc 100644
--- a/examples/misc/load_converter.py
+++ b/examples/misc/load_converter.py
@@ -1,8 +1,10 @@
 """
 ==============
-Load Converter
+Load converter
 ==============
 
+This example demonstrates passing a custom converter to `numpy.genfromtxt` to
+extract dates from a CSV file.
 """
 
 import dateutil.parser
@@ -16,9 +18,9 @@
 
 data = np.genfromtxt(
     datafile, delimiter=',', names=True,
-    converters={0: lambda s: dates.date2num(dateutil.parser.parse(s))})
+    dtype=None, converters={0: dateutil.parser.parse})
 
 fig, ax = plt.subplots()
-ax.plot_date(data['Date'], data['High'], '-')
+ax.plot(data['Date'], data['High'], '-')
 fig.autofmt_xdate()
 plt.show()
diff --git a/lib/matplotlib/dates.py b/lib/matplotlib/dates.py
index ed0f9ae1e45b..016656ab3f61 100644
--- a/lib/matplotlib/dates.py
+++ b/lib/matplotlib/dates.py
@@ -317,6 +317,8 @@ def _from_ordinalf(x, tz=None):
 _from_ordinalf_np_vectorized = np.vectorize(_from_ordinalf)
 
 
+@cbook.deprecated(
+    "3.1", alternative="time.strptime or dateutil.parser.parse or datestr2num")
 class strpdate2num(object):
     """
     Use this class to parse date strings to matplotlib datenums when
@@ -333,6 +335,8 @@ def __call__(self, s):
         return date2num(datetime.datetime(*time.strptime(s, self.fmt)[:6]))
 
 
+@cbook.deprecated(
+    "3.1", alternative="time.strptime or dateutil.parser.parse or datestr2num")
 class bytespdate2num(strpdate2num):
     """
     Use this class to parse date strings to matplotlib datenums when