Glade & Barrens Conservation

What It Is

Glades and barrens are naturally open communities on thin, rocky soils — areas where bedrock is close to the surface and soil development is limited, creating conditions too harsh for closed forest but perfect for a unique assemblage of drought-adapted, sun-loving plants. The Cumberland Plateau region hosts three types:

• Limestone glades — thin soil over limestone bedrock; high pH; most common in the target counties
• Sandstone glades — thin soil over sandstone; acidic; numerous throughout the region
• Dolomite glades — similar to limestone; magnesium-rich soils

Barrens differ from glades in having slightly deeper soils and at least 50% grass cover. Both habitat types are fire-adapted in some forms — but not all.

Why It Matters

Glades and barrens harbor disproportionate biodiversity relative to their small area. They contain rare and regionally endemic plants — including several that exist in only a handful of sites worldwide. The communities themselves persist from the Pleistocene era, when the Cumberland Plateau served as a refugium during glaciation, and they harbor genetic lineages found nowhere else.

Understanding threats correctly: The primary threats to glades are:

1. Lack of fire on fire-maintained glades — allowing woody encroachment
2. Human-caused degradation — conversion to firebreaks, UTV/ORV trail damage, development, and mesophication of surrounding forest (fire exclusion in adjacent forest gradually raises soil moisture and shade, eliminating the dry conditions glades require)
3. Woody encroachment (cedar, privet, honeysuckle) is a real concern but is a consequence of the first two threats, not their cause

Important nuance: Eastern red cedar is a natural component of many glade communities — the vegetation type is called “cedar glade” for a reason. The management goal is to reduce cedar density, not eliminate it. Some glades are maintained entirely by edaphic conditions (thin soil, drought, shallow bedrock) and do not need fire — fire can actually be harmful on those sites. Site-by-site determination is required.

How It’s Done

Woody reduction:

• Focus removal on Chinese privet, Japanese honeysuckle, and encroaching Vaccinium species
• Reduce (do not eliminate) eastern red cedar where it is overtopping and shading glade plants
• Apply stump treatments with triclopyr to prevent resprouting

Prescribed fire:

• Use only on glades determined to be fire-maintained (not edaphically maintained)
• Burn in late winter or early spring — but avoid peak spring ephemeral bloom when rare plants are most vulnerable
• Burn frequency: 3–5 years for fire-maintained glades

Avoid soil disturbance: Glade communities are slow to recover from soil disturbance. Avoid operating equipment on the glade surface. Restrict access during restoration work.

Usually no seeding needed: The glade seed bank typically persists and plants return as light is restored. Supplemental seeding may be appropriate only for species known to have been locally extirpated.

Expected Outcomes

• Year 1: Removal of encroaching invasive shrubs; increased light reaching glade surface
• Year 2–3: Rare glade plants responding with increased vigor and reproduction
• Years 3–5 (fire-maintained glades): Prescribed burning clearing accumulated thatch; expansion of glade plant community
• Long-term: Self-sustaining glade community maintained through periodic burning and invasive monitoring