Department of Plant Sciences, University of California, Davis, California 95616, USA.
Am J Bot. 2013 Apr;100(4):778-91. doi: 10.3732/ajb.1200581. Epub 2013 Mar 19.
Fire in the New Jersey Pine Plains has selectively maintained a dwarf growth form of pitch pine (Pinus rigida), which is distinct from the surrounding tall forest of the Pine Barrens and has several other inherited adaptations that enable it to survive in an environment dominated by fire.
Pitch pine progeny from two Pine Plains sites, the West and East Pine Plains, were grown in common garden environments with progeny from two Pine Barrens stands, Batsto and Great Egg Harbor River. The tests were replicated in five locations: in New Jersey, Connecticut, two sites in Massachusetts, and Korea. One of the tests was monitored for up to 36 yr.
Progeny of Pine Plains origin were, in general, shorter, more crooked, precocious, bore more cones, had a higher frequency of serotinous cones, and had a higher frequency of stem cones than did Pine Barrens progeny, wherever they were grown.
The Pine Plains is an ecotype that has evolved in response to disturbance. The several characters that distinguish it from the surrounding tall forest of the Pine Barrens are inherited. The dwarf stature and crooked form not only enable the ecotype to persist in an environment of frequent fires but also increase its flammability.
新泽西州松平原的火灾选择性地维持了一种矮化的短叶松（Pinus rigida）生长形态，这种形态与周围的松平原的高大森林明显不同，并且具有其他几种遗传适应性，使其能够在以火为主导的环境中生存。
来自两个松平原地点（西松平原和东松平原）的短叶松后代在共同的园林环境中与来自两个松平原林分（巴托斯和大蛋港河）的后代一起生长。这些试验在五个地点进行了重复：在新泽西州、康涅狄格州、马萨诸塞州的两个地点和韩国。其中一个试验进行了长达 36 年的监测。
一般来说，来自松平原的后代比来自松平原的后代更矮、更弯曲、更早熟、结更多的球果、具有更高比例的晚熟球果、具有更高比例的茎球果，无论它们在哪里生长。
松平原是一种对干扰做出反应而进化的生态型。与周围的松平原高大森林区分开来的几个特征是遗传的。矮小的身材和弯曲的形态不仅使生态型能够在频繁发生火灾的环境中持续存在，而且还增加了其可燃性。
