Frequently Asked Questions

What are Illinois Nature Preserves?

Illinois Nature Preserves are biodiversity conservation areas designed to protect some of Illinois’ best original forests, prairies, wetlands, and natural areas. Any landowner whose property contains an ecologically important natural area may choose to dedicate that property as an Illinois Nature Preserve.


To qualify for Nature Preserve status, and area must have high quality plant or animal communities, such as those recognized by the Illinois Natural Areas Inventory (INAI). Once dedicated, a Nature Preserve is protected by state law from development, abuse, and misuse in perpetuity.

Since Nature Preserves are protected primarily for nature’s sake, only nature-compatible recreation is allowed in Nature Preserves. Removal of plant material and animals and most recreation (hunting, fishing, foraging, off-roading, flower-gathering, dog-walking, etc.) are not allowed in Nature Preserves (except with approval in certain, limited cases) in order to keep their rare nature safe and healthy. Nearly 600 Nature Preserves have been dedicated to date.

Most State Park and county Forest Preserves lands are not Nature Preserves, though many Nature Preserves do occur within state park and forest preserve holdings. Nature Preserves can be owned and dedicated by anyone including conservation organizations, government agencies, private individuals, and corporations. The agency that oversees the dedication and maintenance of Nature Preserves is the Illinois Nature Preserves Commission (INPC), which is a part of the Illinois Department of Natural Resources (IDNR).

What are Illinois Land and Water Reserves?

Illinois Land and Water Reserves are legally protected areas that may meet the criteria for Nature Preserve status, but have fewer restrictions on other uses of the preserve.


The exact guidelines for balancing preservation of important ecological or archaeological features with other land uses such as hunting and fishing is decided on by the landowner and INPC staff and board at the time of registration of the Land and Water Reserve. The landowner and INPC may also set legal protections for Land and Water Reserves for a set period of time, instead of in perpetuity.

How do scientists know if an area is or is not ‘natural’?

Natural area is a technical term denoting a biological community that evolved over millennia and consists of diverse species that may have developed their associations over millions of years. The best evidence of a true natural area in Illinois is the abundance of certain rare species of native plants and animals (known as conservative species) that indicate a low level of ecosystem disruption in recent times. As a rule, the more that are found in a place, the higher-quality that area is considered to be. If functional communities of conservative species are found in one area, then it is likely that that area is a true remnant of Illinois nature.


However, because of the continuous changes that have occurred since Euro-American settlement, even remnants have typically lost some ecological quality and diversity. This is especially true of highly-dynamic, fire-dependent ecosystems like prairies, oak savannas, and oak woodlands. To help fully understand original Illinois ecosystems, scientists also look to historical resources, such as the Public Land Survey of Illinois in the 1830s, old aerial photographs, historic eyewitness accounts, and the works of early naturalists. By comparing these sources with ecological realities today, ecologists can make judgments about ecosystem structure and composition in the past. In recent years, high-level restoration projects have also helped piece together parts of the puzzle. There’s still much we don’t know, and we’re learning more every day!

Isn’t it good enough to just leave nature alone?

It actually isn’t good enough to leave nature alone – and that insight has become an inspiration. Our native biodiversity is an irreplaceable local and global treasure, and the main reason behind our Nature Preserves in the first place. Today however it faces grave threats, in part due to “leaving nature alone”.


The belief that people have no role in nature is recent, urban, and false. Modern scholarship recognizes that people, beginning with Native Americans, have always had large-scale positive and negative impacts on biodiversity. Healthy and diverse native ecosystems can suffer not only from obvious human-caused threats like pollution, plowing, clear-cutting, invasive specieshabitat fragmentation, and climate change – but also from the absence of certain human influences that nature evolved with for thousands to millions of years (like fire). Thus, it’s up to us to decide what the legacy of our impacts will be: will they preserve biodiversity, or not? It’s almost as if our native ecosystems are calling upon us to reclaim our former relationship as stewards of the land.

What happens to preserves that are left alone?

Mostly, they degrade. They lose species – a few at first – and in time most species. In this context, degradation means the decline of ecosystem vitality and biodiversity.


Over time (sometimes just a few years), the composition of a healthy and diverse ecosystem will be knocked off-balance and begin to shift toward one dominated by just a few invasive non-native and/or aggressive native species. Without management, the likely end result for most of our Nature Preserves would be complete degradation, biodiversity loss, and the end of millions of years of evolution. Already in a few cases, substantial parts of natural areas preserved to protect a particular rare species or biological community have degraded to the point that they’ve lost many or most of the species or communities for which they were preserved in the first place.

Why isn’t it possible for nature to recover if left alone?

Most of our intact native ecosystems exist today in small, isolated preserves, and their rare species cannot travel from one suitable habitat to another to colonize a new area. Also known as habitat fragmentation, this problem limits the size of their populations, chances of interbreeding, and, ultimately, their prospects for long-term survival. Instead, degraded native ecosystems are often invaded by opportunistic non-native species with which they have no long-term evolutionary relationships. Certain aggressive species then come to dominate, excluding most other species.


Most of our native ecosystems also coevolved with historic, human-caused influences – including hunting and especially regular, dormant-season burning. In the absence of fire, invasive and opportunistic native species (like maple trees in an oak woodland) can spread like cancer through fire-dependent ecosystems. In time, this invasion causes the loss of entire communities of native plant and animal species, many of which used to be quite common but are rare today. In the absence of natural predators (including wolves, mountain lions, and people), overpopulated deer can be equally devastating by reducing plant populations below sustainable levels. Active management seeks to compensate for the lack of these historic influences, without which degraded natural areas cannot revert to their original health and diversity. In the long run, “conservation by restoration” is a key tool for sustainably preserving our precious natural heritage.

What do we do about it?

We volunteers act! Dedicated Nature Preserve staff are faced by greater challenges than they can overcome on their own. They welcome all the good help they can get. Most natural areas require regular management such as invasives control, prescribed burning, monitoring of conservation-priority species, and scouting for general threats to their wellbeing.


Degraded natural areas and buffer lands may also benefit from active restoration in addition to regular management. Restoration aims to restore the natural processes and conditions in ecosystems that have declined to the point that they no longer function like the ecosystem they were previously. This work may entail removing problem species, promoting ecologically appropriate species, restoring original hydrology (removing artificial drainage or flooding), signage, fencing, and education. Restoration of buffer areas around high-quality remnants may help expand habitat for conservation-priority species within the remnant, while also likely improving their efficacy as barriers to external threats. The process of making and enacting management and restoration decisions is part of what we call stewardship. Volunteers have long played and continue to play an important part in the stewardship of our Nature Preserves.

What kind of work do the preserves need?

Each Nature Preserve has unique needs that prompt unique management responses. Preserves that are doing well may not require much else besides regular monitoring for problems, removal of minor inroads by invasive species, and prescribed burns. Preserves that are losing conservation-priority species or communities urgently need remedial help, like intensive invasives control and restoration.


Many preserves have degraded buffer areas that could be restored to better protect the high-quality core. On a broader level, state policymakers need to know that people care for the Illinois Nature Preserves System to receive the full support the preserves need. No matter the particular case, all of our Nature Preserves deserve dedicated stewardship, public support, and constituency.

How can I help the Nature Preserves?

There are many ways to help out that appeal to different interest levels and require different types of skills. To achieve the best protection, our Nature Preserves ultimately need a broad and diverse community of Illinois citizens working on staff-approved plans to keep the preserves the best they can be.


Many of us are inspired by local restoration efforts in needy preserves and come out to cut invasive brush in winter, collect precious local seeds in the summer, or help out in prescribed burns in fall and spring. Others learn to identify and monitor rare plants and animals and as citizen scientists help staff understand changes in the ecosystem. Still others are strong advocates for the Nature Preserves, educating state and local policymakers or contributing funding or services to Nature Preserve partner organizations. Some learn to help in small ways early on and then rapidly become leaders in this new Nature Preserve community. Others start small and then gradually grow into whatever role best suits them. All who care are appreciated and welcome. As the Friends, our vision for the future is one where every Nature Preserve has a dedicated team of local stewards that help owning agencies and Nature Preserves staff ensure natural health and wellbeing. With similar staff-and-volunteer communities all across the state, we defend and cherish the protection and recovery of Illinois’ glorious natural heritage.