One-seed juniper (Juniperus monosperma [Englem.] Sarg.) encroachment into grassland habitats is facilitated by a diverse group of frugivores. To test seed germination after gut passage, we collected pellets or scats containing mature seeds from four frugivore groups: passerine (perching) birds, lagomorphs (hares and rabbits), mesocarnivores (coyotes and foxes), and porcupines. For comparison of germination success, we also evaluated seeds from intact, nondigested one-seed juniper cones. We conducted germination trials under three different scenarios: 1) imbibed bare seeds (a measure of potential germination); 2) seeds still encased within a frugivore deposited pellet or scat matrix or still in a nondigested cone; and 3) matrix-free seeds that had gone through the matrix germination trials and then were freed from the matrix (a simulation of seeds that become dislodged from scats or pellets). In the bare seed trials, germination was highest (70.8% ± 7.4%) for seeds digested by mesocarnivores and was 63.9% ± 5.7% for porcupines, which was higher (P < 0.05) than germination of seeds from bird pellets (33.3% ± 7.7%). Germination of seeds from all frugivores, including lagomorphs (51.4% ± 7.2%), was higher (P < 0.05) than for seeds encased in cones (9.7% ± 3.2%). The germination percentage of seeds still encased in frugivore pellets or scats was highest for birds (40.1 ± 4.2) and was significantly lower (P < 0.05) for other frugivores. Seeds freed from all frugivore deposition matrices showed a second pulse of germination activity, especially seeds from lagomorph pellets. Germination success differences can influence the nature of one-seed juniper woodland infill and encroachment into bordering grasslands, which can lead to loss of soil health, lower grass biomass production, and a diminishment of habitat quality for grassland-dependent wildlife species.

一粒杜松（杜松）[Englem。] Sarg。）各种各样的草食动物促进了对草原栖息地的侵犯。为了测试肠道通过后的种子发芽，我们收集了包含四个节食动物组的成熟种子的丸粒或粪便：雀形目（栖息）鸟，兔形变体（野兔和兔子），中食性食肉动物（土狼和狐狸）和豪猪。为了比较发芽成功率，我们还评估了完整，未消化的单子杜松球果的种子。我们在三种不同情况下进行了发芽试验：1）吸收裸露的种子（衡量潜在发芽的一种方法）；2）种子仍被包埋在节食的小球或粪便基质中或仍未消化的圆锥中；和3）经过基质发芽试验然后从基质中释放出来的无基质种子（模拟从粪便或小球中脱落的种子）。在裸种子试验中，中食肉食动物消化的种子的发芽率最高（70.8％±7.4％），而豪猪的发芽率则最高（63.9％±5.7％）（P <0.05）比鸟类颗粒的种子发芽（33.3％±7.7％）。来自所有节食动物的种子（包括兔形目）的发芽率（51.4％±7.2％）要高于包在圆锥体中的种子（9.7％±3.2％）（P <0.05）。仍被装在节食性小球或粪便中的种子的发芽率对于鸟类最高（40.1±4.2），而相对较低（P<0.05），用于其他节食动物。从所有节食动物沉积基质中释放出来的种子显示出第二次萌发活性脉冲，尤其是来自豆荚型小球的种子。萌发成功差异可能会影响单子杜松林地的填充和侵占临近草地的性质，这可能导致土壤健康损失，草类生物量产量降低以及依赖草地的野生动植物物种的栖息地质量下降。