I took a walk through the scrub during the past two afternoons in search of stray piles of trash (broken glass, etc.) that might be visible after some post-burn weathering of the soil.
During the walk I saw Bonamia beginning to bloom practically everywhere . It responded well to an accidental fire several years ago before the Natal grass came in.
That is still the unanswered question is whether Natal grass will become rife in more sections of the preserve as it has at the sites of the burn piles on the east side. Also, it's unknown whether it will persist or eventually be crowded out by native plants, as some claim. I don't know. Otherwise, we'll have to live with it. Treating it or pulling it on a landscape scale is impractical.