Those the media call scientists, only label them so when it's convenient. "Scientists" are also wary of coffee, red meat -- etcetera.

Like coffee not all Roundup is the same, different brands can have different complexes of Glyphosate, different wetter agents and adjutants.

As best any organisational body that has any sort of authority can state in regard to glyphosate is may -- there are a number of wetter compounds that ARE. At least one type of wetter does not make news because how hysterical some people can be with similar compounds, sister or distant cousin to the offending compound, which is used in cosmetics. [It's apparently a big important industry that any half smart rag or news media isn't game enough to bite on those ever common compounds.]

No doubt the people at the national park do not want any minor grass fire to stuff up new sapling plantings as well as reduce the fuel load around the remaining trees. But bare ground is prone to erosion, so no doubt those in charge are hopefully managing that aspect as well.