Native Plants, Non-native Plants, and Invasive Species
National Parks and other protected areas provide samples of the world's natural and unique variety of life. The value of diverse landscape and wildlife in our National Parks is integral to and necessary for the enjoyment and health of the park and its visitors. We value the environment in many ways: in its infinite source of beauty and enjoyment, for the process of learning about nature from a place of minimal human impact, and for the survival of wild species that help regulate climate, air quality, and the carbon, nitrogen, oxygen and water cycle.
Part of preserving our ecosystem is to understand all forms of life that exist in our parks and beyond. Understanding the relationship between the biotic (living) and abiotic (non-living) interactions in an ecosystem helps to create an effective management program to protect natural resources. Controlling invasive species is one way to protect the biodiversity that make the park special. As the name suggests, biodiversity refers to multitude of living organisms in one area and is a way to gauge the health of the natural community. Invasive species threaten our environment in a very powerful way because they can alter the ecosystems and landscapes we seek to protect. Invasive species are "a non-native species whose introduction does, or is likely to cause, economic or environmental harm or harm to human, animal, or plant health" (Executive Order 13112, 1999). Invasive species aggressively compete with native species and are often the victor of the battle. In some cases, one invasive species can outcompete many native species, thus reducing biodiversity.
Native species are natural to the area in which they are found, and are specially adapted to that particular ecosystem. Native plants are intrinsic to the continuation of a healthy and diverse ecosystem. They provide foodand shelter for mammals, birds and insects and in early summer, beautiful wildflowers dot the meadows within the monument. These systems are fragile and easily damaged: the introduction of non-native plants can have serious consequences. We have a responsibility to protect Devils Postpile National Monument for future generations and one way we can help includes protecting native plants and their specific roles in the monument.
Early summer in the Middle Fork of the San Joaquin River Valley is home to many exquisite wildflowers. One of the best places to explore these colorful landscapes is the Agnew Meadow wildflower walk. The self-guided hike is 0.5 mile. Mid-June through mid-July are the best time to see the most diverse blooms. Look through our common wildflower photo database to help you identify what you find. Plant guides are also available for sale in the Devils Postpile ranger station.
Exotic Plant list Bromus tectorum-Cheatgrass Cirsium vulgareBull- thistle Lactua serriola-Prickly lettuce Phleum pretense-Timothy Poa annualL.- Annual bluegrass Poa pratensis- Kentucky bluegrass Spergularia rubra- Red Sandspurry Taraxcum officinale- Common dandelion Tragopogon dubius- Western salsify Verbascum thapsis- Common mullein
Species of Concern
Bull Thistle-Cirsium vulgare Bull Thistle is native to Europe, Northern Africa, and Asia and found on every continent except for Antarctica. It germinates in spring or fall as a response to soil moisture and is less sensitive to low water availability than other species of thistle. Bull thistle grows well in areas that have recently been disturbed, such as by fire, grazing or other soil disturbances. It competes with native plants and has no nutritional value for wildlife and may prevent tree seedling growth.
Cheatgrass-Bromus tectorum Cheatgrass is native to Europe, Northern Africa, and Asia. It can create a monoculture, growing in pure stands and pushing out all other species. Cheatgrass grows early in cooler temperature and uses soil moisture before native plants can establish themselves. Wind, animals, and people can transport the seeds long distances. Cheatgrass is very flammable and can cause more intense and frequent wildfires. It also reestablishes quickly in areas that have been burned, outcompeting native plants that are slower to establish.
Western Salsify- Tragopogon dubius Western Salsify is native to Eurasia and has been introduced to large parts of North America. Salsify only reproduces by seeds which are stored in a seed head that closely resembles a dandelion. Wind can carry these light seed great distances, spreading Salsify quickly throughout an area. Salsify is common in areas of recent fires or other disturbed areas such as roadsides.
What Can You Do?
1. Don't pick flowers or dig up native plants, we need these populations to be as strong as possible to outcompete invasive species. 2. If you are hiking, camping, or climbing check all of your gear; shoes, backpacks, ropes etc. for seeds caught in your belongings. 3. Burn local wood. Please don't bring wood from outside to burn in your campfires. Wood can carry invasive insects and seeds. 4. Volunteer at Devils Postpile National Monument. Volunteers are crucial to management of invasive species. If you are interested in helping, please contact the park for more information on upcoming trips and project days. 5. Consider using native plants in your home and garden. Native plants need less water, provide habitat for other native species and help reduce the spread of invasive species.
Native Gardens Native gardens are a wonderful way for everyone to help keep the environment healthy. Native plants are well adapted to their surroundings, they use less water and need less maintenance than non-native plants and in some cases have natural resistance to pests. Native gardens also create habitat for native wildlife, so you'll be able to watch nature in your own back yard! The Benefits of Native Gardens include saving water, low maintenance requirments, reducing pesticides and creating a habitat for native wildlife.
Humans are a major source of non-native plant introduction. Try to identify and remove invasive species in your own yard, to help stop the spread of invasive species and keep your native gardens healthy.