For a few weeks each fall the high slopes turn yellow and then gold, and the trees doing it are conifers. Subalpine larch is the one needled tree up there that drops everything, and that surrender is why it can live where it does. Holding needles through an alpine winter means losing water you cannot replace while your roots are frozen, so the larch stops trying. The trade buys ground no evergreen can hold, and larches stand in pure groves above the last spruce and fir, in country that would otherwise be bare tundra. They get old doing it, with one Alberta specimen ring-counted at 838 years. The gold does not linger, so go the week you hear it has started.