diff --git a/volcanic/grid-sources/README.md b/volcanic/grid-sources/README.md
index c0d194eb739b3187e28f556a2182c1f0f8860d23..d453c82f5548cb5f161b70057a940b26cbb28546 100644
--- a/volcanic/grid-sources/README.md
+++ b/volcanic/grid-sources/README.md
@@ -10,9 +10,9 @@ are further subdivided into north and south regions.
 All sub-catalogs were declusterd using nearest-neighbor (`nn`) and Reasenberg (1985; `r85`)
 algorithms prior to smoothing earthquake rates using a single, adaptive kernel approach.
 
-## Gridded rates
+## Gridded Rates
 
-Rates of M = 0.0 earthquakes, `n(M=0)`, given in Table 1 of Petersen et al. (2014) are the
+Rates of M = 0.0 earthquakes, `n(M=0)`, given in Table 1 of Petersen et al. (2021) are the
 incremental Gutenberg-Richter a-value in
 ![formula](https://render.githubusercontent.com/render/math?math=n(m)\=10^{a-bm}). They are
 derived from the total gridded a-value of a rupture set multiplied by a scale factor
@@ -20,20 +20,26 @@ for the catalog time period and declustering method; see grid-source `rate-tree.
 files. Individual point source rates are the product of the total rate and the corresponding
 spatial PDF value. Spatial PDFs were created by normalizing the 1960-2019 catalog a-grid file.
 
-## Source names and IDs
+## Source Names, Source Tree, and Rupture Set IDs
+
+| Region     | Depth           | PDF¹ | Tree ID | Rupture Set ID |
+|------------|-----------------|:----:|:-------:|:--------------:|
+| summit     | deep            |      | 5114    |                |
+|            |                 | nn   |         | 5110           |
+|            |                 | r85  |         | 5111           |
+| summit     | shallow         |      | 5115    |                |
+|            |                 | nn   |         | 5112           |
+|            |                 | r85  |         | 5113           |
+| non-summit | deep            |      | 5126    |                |
+|            |                 | nn   |         | 5120           |
+|            |                 | r85  |         | 5121           |
+| non-summit | shallow (north) |      | 5127    |                |
+|            |                 | nn   |         | 5122           |
+|            |                 | r85  |         | 5123           |
+| non-summit | shallow (south) |      | 5128    |                |
+|            |                 | nn   |         | 5124           |
+|            |                 | r85  |         | 5125           |
 
-Region     | Depth           | PDF¹ | ID
------------|-----------------|------|:--:
-summit     | deep            | nn   | 5110
-summit     | deep            | r85  | 5111
-summit     | shallow         | nn   | 5112
-summit     | shallow         | r85  | 5113
-non-summit | deep            | nn   | 5120
-non-summit | deep            | r85  | 5121
-non-summit | shallow (north) | nn   | 5122
-non-summit | shallow (north) | r85  | 5123
-non-summit | shallow (south) | nn   | 5124
-non-summit | shallow (south) | r85  | 5125
 ---
-¹ Refers to the declustering model ID for the corresponding gridded seismicity spatial probability
-  density function (PDF)
+¹ Refers to the declustering model ID for the corresponding gridded seismicity spatial
+  probability density function (PDF)
diff --git a/volcanic/grid-sources/non-summit/deep/tree-id.json b/volcanic/grid-sources/non-summit/deep/tree-id.json
new file mode 100644
index 0000000000000000000000000000000000000000..0174f836d478249477cc7187365937a4a5c1b847
--- /dev/null
+++ b/volcanic/grid-sources/non-summit/deep/tree-id.json
@@ -0,0 +1,3 @@
+{
+  "id": 5126
+}
diff --git a/volcanic/grid-sources/non-summit/shallow/north/tree-id.json b/volcanic/grid-sources/non-summit/shallow/north/tree-id.json
new file mode 100644
index 0000000000000000000000000000000000000000..41f4a25c323584babde6ceabdf31feb6c098cf32
--- /dev/null
+++ b/volcanic/grid-sources/non-summit/shallow/north/tree-id.json
@@ -0,0 +1,3 @@
+{
+  "id": 5127
+}
diff --git a/volcanic/grid-sources/non-summit/shallow/south/tree-id.json b/volcanic/grid-sources/non-summit/shallow/south/tree-id.json
new file mode 100644
index 0000000000000000000000000000000000000000..ea47590730ba3ac117e294666cabda2bf861afcc
--- /dev/null
+++ b/volcanic/grid-sources/non-summit/shallow/south/tree-id.json
@@ -0,0 +1,3 @@
+{
+  "id": 5128
+}
diff --git a/volcanic/grid-sources/summit/deep/tree-id.json b/volcanic/grid-sources/summit/deep/tree-id.json
new file mode 100644
index 0000000000000000000000000000000000000000..94e3a4e577c483e30649256aefae1479d49c248c
--- /dev/null
+++ b/volcanic/grid-sources/summit/deep/tree-id.json
@@ -0,0 +1,3 @@
+{
+  "id": 5114
+}
diff --git a/volcanic/grid-sources/summit/shallow/tree-id.json b/volcanic/grid-sources/summit/shallow/tree-id.json
new file mode 100644
index 0000000000000000000000000000000000000000..16be8e3815e8c083c93e1db35a5ec2d1eeb0bb6f
--- /dev/null
+++ b/volcanic/grid-sources/summit/shallow/tree-id.json
@@ -0,0 +1,3 @@
+{
+  "id": 5115
+}