Chapter V.  Burn, Baby, Burn

The outcrop represents the north-easternmost extension of the once-widespread San Antonio Prairie.  Because this parcel of land is so steep and rocky, it has not been mowed, grazed, or plowed as far back as anyone can remember, and the current and past landowners have been fantastic about managing for the beautiful and rare plants that grow here.

However, prairies in Texas need periodic fires to keep them open.  Without fire, woody species take hold and eventually crowd out and shade out the grasses and herbs of the prairie.  Many species of herbs actually need fire for their seeds to germinate.

By 2005, it had become clear that this outcrop was long overdue for some brush cutting and a burn.  What used to be a very sunny spot was shaded much of the day by the large junipers.  The yaupon, dogwood, ligustrum (nasty, evil exotic!), and Japanese honeysuckle were all encroaching on the rare plants, there was a large amount of leaf litter, and numbers of the rare Agalinis navasotensis had dwindled to only a few dozen per year.  Moreover, the landowners missed their view out over the valley--it was hidden behind trees and brush.


Time for action!  The landowners, the botanists of the Biology Department at Texas A&M, and employees of the U.S. Fish & Wildlife Service and Texas Parks and Wildlife Department brainstormed and planned a controlled burn for late 2006.  We decided to do the job in December or January, long enough after the fall flowering season for the Agalinis and other plants to have finished dropping seed, but not so early that the new rosettes of spring-flowering plants would be damaged by brush removal or flames.

To obtain baseline data for measuring the success of the burn, we conducted a transect study across a portion of the outcrop.  We identified the plants growing every few centimeters across several meters of slope.  This took a  long time!


The next step was to mark the woody plants destined for removal.  All of the yaupon hollies were tagged, along with all of the Ligustrum, the smaller junipers, some dogwoods, and as much of the Japanese honeysuckle as we could get.  Some of the larger junipers were limbed up, to allow more sunlight under their canopies.  Then we got to work with the chainsaw, the handsaw, the pruners, and some herbicide very carefully applied to cut stumps of things that tend to resprout.  There was a lot for everyone to do, and some of the landowners' employees did much of the brush hauling.

Just before the burn, we dumped buckets of water over the colonies of Coryphantha cacti so they wouldn't be harmed.  Prairie fires burn quickly, but we didn't want to take any chances.

WARNING-- Even a "controlled" burn can be very dangerous.  We had an experienced professional do the actual burning, we had the appropriate permits, and the fire department was standing by on the site.  Untrained individuals should not attempt a controlled burn.

The site was ideal for a controlled burn in many ways.  The road at the base formed a firebreak on two sides, and the moist septic field between the outcrop and the house, along with the mowed lawn, formed another firebreak.  Burning from the bottom of the slope to the top allowed Tim to direct the fire exactly where he wanted it.   He's an artist with a drip torch.


The weather was pefect--cool, humid, and still.  Those of us not actually spreading fire had the opportunity to just watch the flames as they licked at the dry grass.  There's a little pyromaniac in all of us...


The most difficult part was waiting to see the results.  Some of us went back to the outcrop the following spring.  The outcrop was lush beyond our wildest dreams.  Plants we hadn't seen in a decade were flourishing!  Ground plum--once rare here-- was abundant, the grasses were strong and green, and wildflowers spangled the slope. None of the Coryphantha cacti were harmed.  Success!  But what about our rare Agalinis?

We returned in the fall to find hundreds of plants of Agalinis navasotensis!  We could scarcely walk without stepping on them!   And look how tall and gorgeous the Indiangrass (Sorghastrum nutans) was!  That's a real prairie grass, and it clearly benefitted from a good toasting.


We're continuing to monitor the outcrop. As of spring 2008, it still looks great.  There is much more to do--more honeysuckle, Ligustrum, and yaupon to remove; more junipers to limb up; and perhaps successive periodic burns to do to keep the prairie open.  We'll leave a few of the taller junipers for bird habitat and to give the shade-loving plants their place, but we'll try to make sure the outcrop keeps its special prairie magic.

Species List for the Outcrop