Saturday, September 21, 2013

The longest Sugar Pine cone?

Pinus lambertiana has, without doubt, the longest cone of any conifer.  How long? 

  • Botany of California (Brewer, Watson & Gray 1880) – 18 inches
  • Sudworth 1908 – Forest Trees Pacific Slope – to 23 inches
  • Jepson – Silva of California – 1910 – 18 inches
  • Jepson 1923 Manual – 18 inches
  • Flora North America Vol 2 (1993)  – to 50 cm (19.7 inches)
  • Haller & Vivertte in TJM2 – to 60 cm (23½ inches)
  • Wikipedia – to 26 inches
The stated range seems to be on the order of 18-26 inches – variation of about factor of nearly 1.5.  Maximal cone length therefore seems to be a statistic which bears investigation.   For example, in the best on-line conifer cone image collection, Arboretum de Villardebelle  (pinetum.org), their cone is only 13 inches long. 

Given the range of cone size estimates, it becomes evident that Sugar Pine cones 26 inches long need to be fully documented: geographic location, herbarium specimen, publication,  posted photographs.    In most conifers, cone volume is roughly correlated with number of seed.  In white pines, cone length, volume and seeds per cone are under strong genetic control (1).  Hence, record a Sugar Pine with cones >23 inches or so merits publicity.

References:

1. Critchfield, W. B., and B. B. Kinloch. 1986. Sugar pine and its hybrids. Silvae Genetica 35(4):138-145

N.B.  Cone length will likely vary by a small factor related to wet weight - perhaps as much as 10%?  Report dry weight %.

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