Natural regeneration cannot be effectively evaluated by tree density because of spatial heterogeneity typically observed. A proper interpretation of natural regeneration will consider some evaluation of area stocked. However, stocking estimates for natural regeneration are plot-size-dependent. Stocking at the 1-milacre scale is not generally comparable to that on a 4-milacre scale unless a generalized relation with stand density can be established. A generalized relation was first suggested to hold in a paper by Lynch and Schumacher (1941), but this has not been confirmed in subsequent studies. The Lynch and Schumacher hypothesis of a generalized regeneration density-stocking relation across plot size was tested using observations on 60 stands. Results were consistent with Lynch and Schumacher (1941). With evidence of a well-defined relation for plots ranging from 1 to 10 milacres, it appears possible to approximate, for ponderosa pine and associated species, the natural regeneration stocking percentage for a range of stocking standards based solely on observations of regeneration density. Confidence intervals were derived for a range of stocking standards in English units from 1 to 10 milacre and for metric units from 0.0005 hectares to 0.0040 hectares.

中文翻译：

---

北加州针叶树自然再生的放养和密度的相关性

由于通常观察到的空间异质性，自然更新无法通过树木密度进行有效评估。对自然更新的正确解释将考虑对库存区域进行一些评估。然而，自然再生的放养估计取决于地块大小。除非可以建立与林分密度的广义关系，否则 1 英里规模的放养通常无法与 4 英里规模的放养相比。Lynch 和 Schumacher (1941) 在一篇论文中首次提出了广义关系，但这在随后的研究中并未得到证实。Lynch 和 Schumacher 假设是通过对 60 个林分的观察来检验的，即跨小区规模的广义再生密度-放养关系。结果与 Lynch 和 Schumacher (1941) 一致。有证据表明 1 到 10 英里范围内的地块具有明确定义的关系，对于黄松和相关物种，似乎有可能仅根据再生密度的观察来估算一系列放养标准的自然更新放养百分比。置信区间是根据英制单位从 1 到 10 英里和公制单位从 0.0005 公顷到 0.0040 公顷得出的。