Question

finding viewpoint, reasons, and evidence
the light burners proposed to \control\ the destructiveness of the deliberate firing by burning the woods in the spring or fall when sufficiently moist to prevent the fire from seriously injuring either old timber or young trees. a careful study of the area... shows that such control amounts to little or nothing. the light burners ignore... the rapidity with which... sunlight in warm weather dries up the litter in the pine woods. a south slope will be so dry as to make any fire exceedingly hot and destructive before a north slope will burn at all. areas which will burn but lightly and irregularly early in the morning will flare up and consume in the most approved fashion by mid - afternoon. the moisture following light spring or fall rains often disappears so rapidly that the period of \safe\ burning is a matter of hours, not of days. actually to burn the western pineries, as the advocates of this theory propose to burn them, would, if it could be done at all, entail a cost for effective
answer the questions based on your reading of this magazine excerpt.
what is the main issue with controlled burns?
x the cost is too high.
favorable conditions do not last.
controlled burns happen in the spring.
words \safe\ and \control\?
to show that the words are used questionably

Explanation:

The text mentions that the moisture after light spring or fall rains disappears rapidly, making the "safe" burning period short (hours, not days). This indicates that the favorable conditions (moisture - related) for controlled burns do not last. The mention of cost is incorrect as the text's main focus is on the fleeting nature of conditions, not cost. And the fact that controlled burns happen in spring is just part of the context but not the main issue. The use of quotation marks around "safe" and "control" is to question the validity (how safely and controllably the burns really are) of these terms as used by the light burners.

Answer:

For the main issue with controlled burns: Favorable conditions do not last.
For the purpose of quotation marks around "safe" and "control": to show that the words are used questionably.