diff --git a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDataflowHelper.java b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDataflowHelper.java
index 1bef90d..449515f 100644
--- a/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDataflowHelper.java
+++ b/hyracks-storage-am-btree/src/main/java/edu/uci/ics/hyracks/storage/am/btree/dataflow/BTreeDataflowHelper.java
@@ -22,6 +22,7 @@
 import edu.uci.ics.hyracks.storage.am.btree.util.BTreeUtils;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 
 public class BTreeDataflowHelper extends TreeIndexDataflowHelper {
@@ -31,6 +32,7 @@
 
     @Override
     public ITreeIndex createIndexInstance() throws HyracksDataException {
+        ITreeIndexOperatorDescriptor treeOpDesc = (ITreeIndexOperatorDescriptor) opDesc;
         try {
             return BTreeUtils.createBTree(opDesc.getStorageManager().getBufferCache(ctx), opDesc.getStorageManager()
                     .getFileMapProvider(ctx), treeOpDesc.getTreeIndexTypeTraits(), treeOpDesc
diff --git a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDataflowHelper.java b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDataflowHelper.java
index 0185500..711dfe0 100644
--- a/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDataflowHelper.java
+++ b/hyracks-storage-am-common/src/main/java/edu/uci/ics/hyracks/storage/am/common/dataflow/TreeIndexDataflowHelper.java
@@ -22,11 +22,9 @@
 import edu.uci.ics.hyracks.storage.am.common.impls.TreeIndexDiskOrderScanCursor;
 
 public abstract class TreeIndexDataflowHelper extends IndexDataflowHelper {
-    protected ITreeIndexOperatorDescriptor treeOpDesc;
 
     public TreeIndexDataflowHelper(IIndexOperatorDescriptor opDesc, IHyracksTaskContext ctx, int partition) {
         super(opDesc, ctx, partition);
-        this.treeOpDesc = (ITreeIndexOperatorDescriptor) opDesc;
     }
 
     public ITreeIndexCursor createDiskOrderScanCursor(ITreeIndexFrame leafFrame) throws HyracksDataException {
diff --git a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeDataflowHelper.java b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeDataflowHelper.java
index 0ee1a93..ce6323f 100644
--- a/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeDataflowHelper.java
+++ b/hyracks-storage-am-rtree/src/main/java/edu/uci/ics/hyracks/storage/am/rtree/dataflow/RTreeDataflowHelper.java
@@ -20,6 +20,7 @@
 import edu.uci.ics.hyracks.storage.am.common.api.IPrimitiveValueProviderFactory;
 import edu.uci.ics.hyracks.storage.am.common.api.ITreeIndex;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.IIndexOperatorDescriptor;
+import edu.uci.ics.hyracks.storage.am.common.dataflow.ITreeIndexOperatorDescriptor;
 import edu.uci.ics.hyracks.storage.am.common.dataflow.TreeIndexDataflowHelper;
 import edu.uci.ics.hyracks.storage.am.rtree.frames.RTreePolicyType;
 import edu.uci.ics.hyracks.storage.am.rtree.util.RTreeUtils;
@@ -38,6 +39,7 @@
 
     @Override
     public ITreeIndex createIndexInstance() throws HyracksDataException {
+        ITreeIndexOperatorDescriptor treeOpDesc = (ITreeIndexOperatorDescriptor) opDesc;
         return RTreeUtils.createRTree(treeOpDesc.getStorageManager().getBufferCache(ctx), treeOpDesc
                 .getStorageManager().getFileMapProvider(ctx), treeOpDesc.getTreeIndexTypeTraits(),
                 valueProviderFactories, treeOpDesc.getTreeIndexComparatorFactories(), rtreePolicyType, file);