Word: firs
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Dates: during 1970-1979
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...TURNS out that the balsam fir used to make the paper towels produce a compound very similar to the bug's juvenile hormone. But unlike the silkworm hormone, it hits only a single family of bugs. If nature can provide such highly specific insecticides through evolution, Williams argues, man should be able to develop some himself...
Swept east by wind, the city's smog is killing the forest's majestic ponderosa pines at the rate of 3% a year. Incense cedar and white fir have also suffered. In all, the smog has caused moderate to severe damage in 60% of the forest's 160,000 acres of pines. Last week loggers began cutting down dead trees in the hardest hit 1,000 acres...