diff --git a/chain/src/pipe.rs b/chain/src/pipe.rs
index f04314e5..8247ca83 100644
--- a/chain/src/pipe.rs
+++ b/chain/src/pipe.rs
@@ -265,6 +265,7 @@ fn validate_block(b: &Block,
 	if utxo_root.hash != b.header.utxo_root || rproof_root.hash != b.header.range_proof_root ||
 	   kernel_root.hash != b.header.kernel_root {
 
+		ext.dump();
 		return Err(Error::InvalidRoot);
 	}
 
diff --git a/chain/src/sumtree.rs b/chain/src/sumtree.rs
index 561ae4e3..abd48447 100644
--- a/chain/src/sumtree.rs
+++ b/chain/src/sumtree.rs
@@ -284,6 +284,16 @@ impl<'a> Extension<'a> {
 		self.rollback = true;
 	}
 
+	/// Dumps the state of the 3 sum trees to stdout for debugging
+	pub fn dump(&self) {
+		println!("-- outputs --");
+		self.output_pmmr.dump();
+		println!("-- range proofs --");
+		self.rproof_pmmr.dump();
+		println!("-- kernels --");
+		self.kernel_pmmr.dump();
+	}
+
 	// Sizes of the sum trees, used by `extending` on rollback.
 	fn sizes(&self) -> (u64, u64, u64) {
 		(self.output_pmmr.unpruned_size(),