Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Flowering and Fruiting in the White Oaks. Pistillate Flowering, Acorn Development, Weather, and Yields

Ward M. Sharp and Vance G. Sprague
Ecology
Vol. 48, No. 2 (Mar., 1967), pp. 243-251
Published by: Wiley
DOI: 10.2307/1933106
Stable URL: http://www.jstor.org/stable/1933106
Page Count: 9
  • Download ($42.00)
  • Subscribe ($19.50)
  • Cite this Item
Flowering and Fruiting in the White Oaks. Pistillate Flowering, Acorn Development, Weather, and Yields
Preview not available

Abstract

Female flowering and acorn development in three species of which oaks were studied in Pennsylvania from April 1949 through August 1962 with emphasis on the effect of weather on floral development and acorn production. Pistillate flowers emerge in late April or early May, 5-10 days after the appearance of staminate flowers. After pollination and fertilization, developemnt of acorn forms begins, and filled acorns mature late in August. Spring air temperatures strongly affect acorn yields. Good white oak acorn crops were obtained in years when a warm 10-day period occurred late in April, with average night temperatures 55-60@?F, followed by cooler periods (45-50@?F) for 13-20 days early in May. During years when April remained cool and was followed by warm days and nights in May, acorn production was poor. Wind, precipitation, relative humidity, and vapor pressure deficits did not significantly influence acorn yields. While some individual trees were inherently copious acorn producers, others in the same stand produced none or a light crop throughout the 14-year period.

Page Thumbnails

  • Thumbnail: Page 
[243]
    [243]
  • Thumbnail: Page 
244
    244
  • Thumbnail: Page 
245
    245
  • Thumbnail: Page 
246
    246
  • Thumbnail: Page 
247
    247
  • Thumbnail: Page 
248
    248
  • Thumbnail: Page 
249
    249
  • Thumbnail: Page 
250
    250
  • Thumbnail: Page 
251
    251