New Research from Africa Shows How Closed-canopy Forest Survive Alongside Grasslands
This paper is an amazing study of fire ecology of grasslands and forest and can be readily applied to Texas karst country. Basically, the research team found forests are protected from grassland fires in four ways. I've summarized these strategies here:
LONG-TERM STABILITY
Shade: forests create and sustain shade to reduce spread of sun-loving flammable grasses for 100s to 1000s of years.
Sun: grasslands remain open to top-kill new woody saplings
TOPOGRAPHY
Protected areas: low spots tend to be safe from fire
Slope induced wind patterns: can force fires to be carried around forests or leave regenerating forest untouched
EDGE FUEL
Fire buffers: dense, partly-shaded, vegetated edges surrounding the forest that contain less flammable C4 and C3 species to reduce intensity of grassland fires
Forest Edge Canopy Trees: act with fire buffers to protect interior, more-flammable trees (for example, Texas Red Oaks in TKC).
FIRE BREAKS
Discontinuous cover: bare ground or recently reduced grass cover (such as caused by grazing, tornado, stampedes).
Broken terrain: slows and/or redirects groundfires (common in Texas karst country, not Africa)