Mapping Weeds – Experiences from the National Park Service

By Kristina Stine

I work in the Environmental Assessment and Monitoring Branch of EPA here in Region 7, home to our Geospatial program and GIS!I spent a wonderful summer as an intern for the National Park Service eradicating noxious weed in the Theodore Roosevelt National Park in North Dakota.  Our team   was tasked with managing leafy spurge (euphorbia esula), Russian Knapweed (Rhaponticum repens (L.) Hidalgo), and Canada Thistle (Cirsium arvense (L.) Scop).

University of Wyoming Extension Sustainable Management of Rangeland Resources Initiative Team – Leafy Spruge

We used biological control, pesticides, goats, and prescribed burns to control the spread and eradicate the plants.   For our summer project, we extensively used GPS/GIS to track yearly progress and eventually determine when the plants were contained and ultimately destroyed.

Non-Federal rangeland where non-native species make up at least 50% of the plant cover (USDA)

One of the tools I became familiar with during our excursions, the Precision Lightweight GPS Receiver (PLGR), was known as the “plugger” or better known as a GPS (see “Happy Belated Veterans Day: GIs and GPS” by Joe Summerlin).  After picking out our site, we’d enter in our coordinates and set our way in the wilderness to find a patch of leafy spurge or other targeted weed.  Once we made our way to the exact coordinates, we would verify the actual plant locations and then make corrections as necessary.  If we had our Trimble unit, we would take a continuous track of the infested areas.  Depending on our control measure, we would also records the data for each of the different control strategies we employed.   After collecting data and managing the site with pest control (depending on the site and weed variety) we would take the plugger to the GIS Specialists and they would create a map summarizing our summer efforts.   Every year this is done until the site is restored back to its natural, native state.

Controlling noxious weeds take time and a measured approach.  The map below shows polygons defined by GPS in red while the black blocks represent areas overrun with leafy spurge. Without breaking into the details (see the Theodore Roosevelt National Park Invasive Leafy Spurge Remote Sensing Research ) one can see that a combination of GPS and remotely sensed data can really help with monitoring and controlling noxious weed populations – and determining the effectiveness of various control strategies.

Theodore Roosevelt National Park Invasive Leafy Spurge Remote Sensing Research

My summers out in the field as an intern for the National Park service has really helped me appreciate the power of location and GIS in caring for our environment.  The infected sites were managed yearly and the data recorded so that we could see what practices were most effective. Similar maps like the previous one were made on a regular basis to monitor the increase/decrease of noxious and invasive species of plants.  It helped give us, decision makers, and the general public a visual understanding of noxious weeds in our National Parks.  Please remember to be careful what you plant in your yard!

Kristina Stine is a first generation Environmental Biologist who has worked with the federal government since 1997. She is currently working for the U.S. EPA Region 7 as a secretary. Some of her most memorable jobs were working as an intern for the National Park Service as a Biological Technician (and Wildland Firefighter) at Theodore Roosevelt National Park in North Dakota and Wind Cave National Park in South Dakota.

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