diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index d87fbb01620..90e9973c3f3 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -36,6 +36,7 @@ extern crate rustc_llvm;
 extern crate rustc_back;
 extern crate serialize;
 extern crate rbml;
+extern crate collections;
 #[phase(plugin, link)] extern crate log;
 #[phase(plugin, link)] extern crate syntax;
 
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index b349b5ca0bf..0ad07bed7d9 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -77,7 +77,7 @@ use std::hash::{Hash, sip, Writer};
 use std::mem;
 use std::ops;
 use std::rc::Rc;
-use std::collections::enum_set::{EnumSet, CLike};
+use collections::enum_set::{EnumSet, CLike};
 use std::collections::hash_map::{HashMap, Occupied, Vacant};
 use syntax::abi;
 use syntax::ast::{CrateNum, DefId, DUMMY_NODE_ID, Ident, ItemTrait, LOCAL_CRATE};
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 5a91298acdf..3d51a6d6ab0 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -472,7 +472,7 @@ fn json_output(krate: clean::Crate, res: Vec<plugins::PluginJson> ,
     //   "crate": { parsed crate ... },
     //   "plugins": { output of plugins ... }
     // }
-    let mut json = std::collections::TreeMap::new();
+    let mut json = std::collections::BTreeMap::new();
     json.insert("schema".to_string(), Json::String(SCHEMA_VERSION.to_string()));
     let plugins_json = res.into_iter()
                           .filter_map(|opt| {
diff --git a/src/libserialize/collection_impls.rs b/src/libserialize/collection_impls.rs
index 8fb025623d4..f2d79b13346 100644
--- a/src/libserialize/collection_impls.rs
+++ b/src/libserialize/collection_impls.rs
@@ -15,9 +15,8 @@ use std::default::Default;
 use std::hash::{Hash, Hasher};
 
 use {Decodable, Encodable, Decoder, Encoder};
-use std::collections::{DList, RingBuf, BTreeMap, BTreeSet, HashMap, HashSet,
-                       TrieMap, TrieSet, VecMap};
-use std::collections::enum_set::{EnumSet, CLike};
+use std::collections::{DList, RingBuf, BTreeMap, BTreeSet, HashMap, HashSet, VecMap};
+use collections::enum_set::{EnumSet, CLike};
 
 impl<
     E,
@@ -98,7 +97,7 @@ impl<
     K: Decodable<D, E> + PartialEq + Ord,
     V: Decodable<D, E> + PartialEq
 > Decodable<D, E> for BTreeMap<K, V> {
-    fn decode(d: &mut D) -> Result<TreeMap<K, V>, E> {
+    fn decode(d: &mut D) -> Result<BTreeMap<K, V>, E> {
         d.read_map(|d, len| {
             let mut map = BTreeMap::new();
             for i in range(0u, len) {
@@ -133,7 +132,7 @@ impl<
     D: Decoder<E>,
     T: Decodable<D, E> + PartialEq + Ord
 > Decodable<D, E> for BTreeSet<T> {
-    fn decode(d: &mut D) -> Result<TreeSet<T>, E> {
+    fn decode(d: &mut D) -> Result<BTreeSet<T>, E> {
         d.read_seq(|d, len| {
             let mut set = BTreeSet::new();
             for i in range(0u, len) {
@@ -255,63 +254,6 @@ impl<
     }
 }
 
-impl<
-    E,
-    S: Encoder<E>,
-    V: Encodable<S, E>
-> Encodable<S, E> for TrieMap<V> {
-    fn encode(&self, e: &mut S) -> Result<(), E> {
-        e.emit_map(self.len(), |e| {
-                for (i, (key, val)) in self.iter().enumerate() {
-                    try!(e.emit_map_elt_key(i, |e| key.encode(e)));
-                    try!(e.emit_map_elt_val(i, |e| val.encode(e)));
-                }
-                Ok(())
-            })
-    }
-}
-
-impl<
-    E,
-    D: Decoder<E>,
-    V: Decodable<D, E>
-> Decodable<D, E> for TrieMap<V> {
-    fn decode(d: &mut D) -> Result<TrieMap<V>, E> {
-        d.read_map(|d, len| {
-            let mut map = TrieMap::new();
-            for i in range(0u, len) {
-                let key = try!(d.read_map_elt_key(i, |d| Decodable::decode(d)));
-                let val = try!(d.read_map_elt_val(i, |d| Decodable::decode(d)));
-                map.insert(key, val);
-            }
-            Ok(map)
-        })
-    }
-}
-
-impl<E, S: Encoder<E>> Encodable<S, E> for TrieSet {
-    fn encode(&self, s: &mut S) -> Result<(), E> {
-        s.emit_seq(self.len(), |s| {
-                for (i, e) in self.iter().enumerate() {
-                    try!(s.emit_seq_elt(i, |s| e.encode(s)));
-                }
-                Ok(())
-            })
-    }
-}
-
-impl<E, D: Decoder<E>> Decodable<D, E> for TrieSet {
-    fn decode(d: &mut D) -> Result<TrieSet, E> {
-        d.read_seq(|d, len| {
-            let mut set = TrieSet::new();
-            for i in range(0u, len) {
-                set.insert(try!(d.read_seq_elt(i, |d| Decodable::decode(d))));
-            }
-            Ok(set)
-        })
-    }
-}
-
 impl<
     E,
     S: Encoder<E>,
diff --git a/src/libserialize/lib.rs b/src/libserialize/lib.rs
index 390b3976562..e700d102fef 100644
--- a/src/libserialize/lib.rs
+++ b/src/libserialize/lib.rs
@@ -33,6 +33,8 @@ extern crate test;
 #[phase(plugin, link)]
 extern crate log;
 
+extern crate collections;
+
 pub use self::serialize::{Decoder, Encoder, Decodable, Encodable,
                           DecoderHelpers, EncoderHelpers};
 
diff --git a/src/libtest/lib.rs b/src/libtest/lib.rs
index 02b266b8fe0..d786409e895 100644
--- a/src/libtest/lib.rs
+++ b/src/libtest/lib.rs
@@ -49,7 +49,7 @@ use self::NamePadding::*;
 use self::OutputLocation::*;
 
 use std::any::{Any, AnyRefExt};
-use std::collections::TreeMap;
+use std::collections::BTreeMap;
 use stats::Stats;
 use getopts::{OptGroup, optflag, optopt};
 use regex::Regex;
@@ -230,7 +230,7 @@ impl Metric {
 }
 
 #[deriving(PartialEq)]
-pub struct MetricMap(TreeMap<String,Metric>);
+pub struct MetricMap(BTreeMap<String,Metric>);
 
 impl Clone for MetricMap {
     fn clone(&self) -> MetricMap {
@@ -1191,7 +1191,7 @@ fn calc_result(desc: &TestDesc, task_result: Result<(), Box<Any+Send>>) -> TestR
 impl MetricMap {
 
     pub fn new() -> MetricMap {
-        MetricMap(TreeMap::new())
+        MetricMap(BTreeMap::new())
     }
 
     /// Load MetricDiff from a file.
diff --git a/src/test/run-pass/send_str_treemap.rs b/src/test/run-pass/send_str_treemap.rs
index ee57d01c36d..24480d85272 100644
--- a/src/test/run-pass/send_str_treemap.rs
+++ b/src/test/run-pass/send_str_treemap.rs
@@ -10,7 +10,7 @@
 
 extern crate collections;
 
-use self::collections::TreeMap;
+use self::collections::BTreeMap;
 use std::option::Option::Some;
 use std::str::SendStr;
 use std::string::ToString;