Map Your Own Backyard (or Park)
Irene Foelschow
Sure, everyone uses maps to navigate, but did you know they can help us fight erosion, determine which plants will have the most chance of success, and even identify possible patches of oak wilt? I attended Woodland Ecologist Karl Flocke’s lecture on mapping and wanted to share all the wonderful, free mapping resources available for Texans. I also want to thank Dick McBride, our HELM mapping guru, for his feedback on this article.
Texas A&M’s Map My Property
When you first open Map My Property, it offers you a tour. I recommend you take it. There’re quite a few useful features, and I won’t be able to cover them all here. All done? Great! Let me show you around.
First, let’s find your property. Click on “Search” in the upper left corner or the magnifying glass and type in your address. I’ll demonstrate with my favorite park, Purgatory Creek Natural Area.
Hmm… That didn’t work so well. You can see the blue pin isn’t really where Purgatory Creek Natural Area is labeled. I tried this with my home address and that worked perfectly, so I think this is just an issue with my search term for the park. Anyway, once you’ve located your desired area, we can make some property lines.
Whew! Hopefully your boundaries have fewer corners than mine did. Consider saving your boundary by selecting the “SAVE” button in the “Draw My Ranch” menu. This will download a file on your computer that you can “LOAD” if you close out of this website and return later.
Are you still with me? Great! Now the fun begins! Hays County is known for its sporadic, heavy rains, so water flow plays a huge role in the health of our land, regardless of size. In the “Layers” box, check “Contours.” These lines map where the land is exactly the same height above sea level in 20 foot increments. When the lines are close together, that means the land will be steep. When the contours form long “U” shapes in sequence, that’s an indication of a crevasse. These are places where water will flow. The bottom of the U will always point upstream.
If we check “Flood Zones,” we see how they line up with these contours. Risky places are found in crevasses and near steep grades. In general, our goal is to find ways to slow down water flow. Use these maps to pinpoint where you should strategically keep or place thick vegetation, rocks, and logs to force the water to zigzag back and forth instead of rushing straight through.
Water doesn’t respect land parcel boundaries, so now is a great time to zoom out and see how you and your neighbors affect one another. Which properties drain onto yours, and which ones does yours drain onto? Uncheck “Contours” and “Flood Zones,” zoom out even further, and check “Hydrology.” You should be able to see some of your local rivers and streams. Which one does your property drain to? Consider what’s draining off your and your neighbors’ land. Are there any pesticides or other harmful chemicals currently in use that might affect the health of our rivers?
Next, let’s check for signs of Oak Wilt. Uncheck “Hydrology” and click on the square above “Layers” (the one with four boxes). Then, click on the orange picture of Texas labeled “TX Color Infrared.” These infrared photos are taken during the spring when all trees have leaves. Thus, grey patches in these photos indicate dead or dying trees. Spreading grey areas in the middle of a forest are bad news. Fortunately, it looks like Purgatory Creek is doing all right.
Finally, let’s check out vegetation and geology. Set either “Bing Hybrid” or “Aerial” as your Basemap, and then click on “Themes” in the left hand menu. Don’t worry about soil for now. Check either TX Vegetation or TX Geology and then check the boxes for “Visible” and “Identify.” Last, click and drag the transparency down from 100% to around 50%. You should see a bunch of colors painting your map. Double click on any color to learn more. With TX Vegetation, you can click on the links in the box that pops up to get directed to a detailed description of the plants found in that area.
Web Soil Survey
Now it’s soil’s time to shine! Go to the Web Soil Survey website to get started. Under the “Quick Navigation” section on the left, click on the double down-arrow button next to “Address” and type your address in. Use the magnifying glass icons with the plus and minus symbols above the map to zoom in or out and the hand icon to pan around the map.
Once you’ve located your property, you’ll need to draw an “Area of Interest (AOI)” around the place you’d like surveyed. Above the map you’ll see two buttons with red shapes and the letters “AOI” below. The second button allows you to draw any polygon so that you may draw your property boundaries as you did with the previous website. Personally, I don’t want to make such a complex shape again, so I’m going to use the first AOI button with the red rectangle to click and drag a rectangle around the Purgatory Creek area.
Once you’ve done this, the previously grayed out tabs will become accessible. Click on the Soil Map tab. You’ll see a map of all the types of soil on your land, with a legend on the left hand side.
Click on a blue “Map Unit Name,” and it will load a pop up window with information on that particular soil type. Each unit has a mix of soil types. You can see the percentage you can expect to find of each type under “Map Unit Composition.” For example, the Comfort-Rock outcrop complex is 70% Comfort and similar soils, 15% Rock outcrop, and 15% minor components (this means there’s a bunch of soils that could be here that make up less than 10%). The “Description of Comfort Setting” section is probably the most important here since it makes up the majority of the soil you’ll find in this area of the map. We can see different layers of the soil under “Typical Profile” and information on drainage, runoff, flooding, and salinity. This can help guide you to the types of plants that can thrive in your soil and which to avoid.
If you have more time, I recommend you check out the Soil Data Explorer tab and just click around. There’s a ton of information in there, just waiting for you to explore.
Google Earth
Does history tickle your fancy? Then Google Earth is the right mapping tool for you. Go to https://earth.google.com/web/ and click on the helm/ship steering wheel icon.
Select “Timelapse in Google Earth,” and then type your address in the search bar on the right.
Now you can select aerial imagery as far back as 1984 to see what’s changed in your area. 1995 is when the resolution gets good enough to see more details. Toggle the play and pause button next to the dates in the upper right to watch your area develop over time.
Oh! You’re still with me? Thanks so much for taking the time to zoom out and look at not only your land as a whole, but also its external connections in space and time. Hope you’ve enjoyed!
