How to Find American Chestnut Trees in the Wild

Part 1: Using iNaturalist to find American chestnut observations

1. Open the iNaturalist app on your phone.
2. Click the ‘Explore’ button (bottom menu).
3. Click the filter icon (upper right).
4. Under Taxon, click ‘Search For Taxon’.
5. Type “Castanea” (the genus of chestnuts) in the search bar and select American Chestnut from the list that auto-populates below.
6. On the Explore Filters settings page, you can optionally uncheck the ‘Needs ID’ box to show only Research Grade observations and increase your chances of seeing a confirmed American chestnut.
7. Click ‘Apply Filters’ (green button at bottom).
8. Navigate around the map to find an area to search, or tap the ‘My Location’ icon (small compass lower left) to center the map on your position.
9. When you move the map, click the ‘Redo Search in Map Area’ (green button top) to show results in that map area. The observations will appear as small green pin icons on the map.
10. Zoom in on an area with several observations that seem likely to be in a publicly accessible location. Parks and protected areas are usually large green areas on the map.
11. Tap one of the observation points to open the data for that observation.
12. Tap the photo at the top of the observation page to view a gallery of images submitted with the observation. If you have some experience identifying American chestnut, you can use the photos to decide if this is a good specimen to look for. Visit TACF’s ID page to learn more about identification.
13. Once you’ve found an area with a few promising observations, switch to AllTrails to confirm they are in a public location (see below).
14. Tip: When searching on the map, tap the basemap icon (lower left, next to the ‘My Location’ icon) to switch between satellite imagery and street map. Using satellite imagery can help determine if the tree is in someone’s backyard (private property) or in a large patch of forest, which has a better chance of being public lands.

Part 2. Using AllTrails to find public trails near American chestnut observations

1. Open the AllTrails app.
2. Click in the search field at the top.
3. Tap ‘Current location’ in the list that appears below the search field. This will open a map of trails centered on your current location.
4. Navigate to the same area where you found American chestnut observations in iNaturalist.
5. If you see trails in that area (appearing as dashed black lines), tap the black map pin attached to the trail.
6. Click the preview of the trail that opens at the bottom of the map.
7. Click the ‘Map’ button (bottom right).
8. Click the ‘Start’ button (bottom right).
9. Click ‘Get directions’ (black button in center).
10. Select the mapping app you’d like to use (for example Google Maps).
11. Your mapping app will open and give you driving directions to the trailhead.

Part 3. Using iNaturalist and AllTrails in tandem to navigate to an observation

1. When you arrive at the trailhead, open iNaturalist to see the general location of an American chestnut observation.
2. Open AllTrails to use trails to navigate as close as possible to the area of the observation.
3. Switch back and forth between iNaturalist and AllTrails to navigate to the observation. Try to stay on trails and observe local regulations about hiking off trail!
4. When you arrive at the location, check the photos of the observation to get a sense of what you’re looking for.
5. Start searching the area for an American chestnut!
6. If you don’t find it, don’t despair! If the observation is several years old, the tree may have died back from blight already. Keep trying with other observations in the area.

Part 4. Using PlantNet to identify an American chestnut

1. When you have found a tree that you think is an American chestnut (the majority of which will be small and shrubby) open the PlantNet app.
2. Tap the ‘Touch to Identify’ icon (large green camera icon in the center).
3. Point your camera at several leaves against a simple background, like the ground, and click the photo button.
4. Tap ‘Use Photo’ (lower right corner).
5. Select ‘Leaf’. PlantNet will send the photo for analysis.
6. A list of species will appear below your image with the most likely match at the top. If American chestnut shows up at the top, then there is a good* chance you’ve found an American chestnut!

*I have both American chestnut and Chinese chestnut growing in my yard, and PlantNet gets them right most of the time, but not ALL the time, so celebrate cautiously. If you’re using the new iNaturalist app, you can identify plants directly in the app by tapping the camera icon. But unlike PlantNet, it doesn’t give a list of the most likely matches and I find it to be slightly less accurate than PlantNet.

Part 5. How to download iNaturalist coordinates for offline use

You can’t download iNaturalist maps for offline use, but you can save the coordinates from individual observations and enter them as waypoints into another GPS hiking app like Gaia GPS. Keep in mind that you’ll need a paid subscription with Gaia GPS to download maps for offline use.

1. Open iNaturalist on your mobile phone while you have an internet connection and follow steps 1-11 from Part 1 above.
2. On the observation page, scroll all the way to the bottom and tap ‘View in browser’. This will open the same observation in the iNaturalist website in a web browser.
3. In the browser, the writing will now be tiny on your screen so pinch to zoom into the upper right corner of the page showing the map.
4. Tap the ‘Details’ link (blue text just below the map).
5. In the box that pops up, the latitude and longitude coordinates will appear in the top left. Click the ‘Copy’ icon next to them (a small clipboard and paper icon). A message will pop up that says ‘Copied!’.
6. Open Gaia GPS on your phone.
7. Tap the search icon (magnifying glass, lower right).
8. Tap once inside the search field at the top to open the keyboard, tap again in the search field to get the ‘Paste’ option to appear and tap ‘Paste’.
9. Tap the entered coordinates just below the search field to load the point into the map.
10. Tap the ‘Save’ button (middle right) to save the waypoint.
11. Tap the ‘Edit’ button to change the name of the waypoint. Here you can delete the default name (the coordinates you entered) and change it to something more descriptive like American chestnut.
12. Return to the main map and tap the new waypoint. Info for the waypoint will pop up.
13. Tap the ‘More’ button (three dots) and select ‘Download Maps’. (This option will be greyed out with a free account.) If you have a free account and cell reception, you can select ‘Guide Me’ from this menu and navigate to the point.

How can finding American chestnuts help save the species?

The American Chestnut Foundation (TACF) is working to breed trees with resistance to both chestnut blight and another introduced disease, Phytophthora root rot. The goal is to reintroduce American chestnuts that can once again survive and reproduce in the wild.
The remaining wild trees are essential to this work. They provide regionally adapted genetics and the diversity needed for the species to keep evolving in our rapidly changing forests.
You can help this effort by learning how to identify American chestnuts in the wild and recording your observations with apps like TreeSnap and iNaturalist. You can also send in a sample for identification. TACF staff and volunteers use these reports to collect material for Germplasm Conservation Orchards, which preserve genetic lines for future breeding efforts.