The Cassia crossbill (Loxia sinesciuris) feeds exclusively on seeds held in serotinous cones of lodgepole pine (Pinus contorta latifolia). Its population, confined to 67 km² of pine in southern Idaho, declined by ~ 80% between 2003 and 2011 apparently because an increase in the occurrence of hot summer days (≥32 °C) caused the serotinous cones to open and shed their seeds. We hypothesized that the propensity for serotinous cones to open varies across the landscape depending on the maximum temperatures cones experienced. We tested a suite of abiotic variables for predicting the occurrence of open serotinous cones among 1547 trees at 170 sites. The best-supported model indicated that trees with open cones were less frequent on northeastern aspects and as slope increased. Fewer open cones were expected on northeast aspects because they receive less direct solar radiation. However, the decrease in trees with open cones as slope increased on southwest aspects was unexpected. Increased convection on slopes could reduce maximum cone temperatures and account for the decrease of open cones on steeper slopes, regardless of aspects. Although cones are less likely to open on steeper slopes, slopes with southerly aspects are likely the least favorable for pine recruitment and survival. The most favorable sites for both lodgepole pine and the persistence of closed cones are slopes on northeast aspects. Such locations are often dominated by subalpine fir (Abies bifolia). Reforestation of fir-dominated areas with lodgepole pine, therefore, provides a means to expand microclimatic refugia for Cassia crossbills.

决明子cross（Loxia sinesciuris）仅以种子存放在五倍子松（Pinus contorta latifolia）的乳状圆锥体中的种子为食。其人口仅限于67 km ²爱达荷州南部的松树数量在2003年至2011年之间下降了约80％，这显然是因为炎热的夏季（≥32°C）发生率的增加导致发芽的视锥打开并撒下了种子。我们假设，视锥细胞所经历的最高温度，在整个景观中，锥形视锥细胞开放的倾向各不相同。我们测试了一组非生物变量，以预测170个站点上1547棵树中开放的血清素锥的发生。最佳支持的模型表明，在东北方面，随着锥度的增加，开阔的果树的频率降低。预计东北地区的裸露圆锥较少，因为它们受到的直接太阳辐射较少。但是，随着西南坡度的增加，开阔的果树的减少是出乎意料的。斜坡上的对流增加可能会降低最高圆锥温度，并考虑到陡峭斜坡上开放圆锥的减少，无论如何考虑。尽管在较陡峭的山坡上圆锥形的可能性较小，但向南倾斜的山坡对松树的招募和生存最不利。寄主松和封闭圆锥体的持久性最有利的地方是东北方面的斜坡。这些位置通常以亚高山冷杉为主（冷杉（Abies bifolia））。因此，用黑松木对冷杉为主的地区进行植树造林，可以为决明子交叉b提供扩大小气候避难所的手段。