page_title: Seed
section_title: By wind (anemochory)
hierarchical_section_title: Seed / Functions / Dispersal / By wind (anemochory)
caption_attribution_description: Asclepias syriaca (Common Milkweed), gone to seed -- Forks of the Credit Provincial Park, Ontario, Canada -- 2006 October
context_page_description: A seed is an embryonic plant enclosed in a protective outer covering. The formation of the seed is part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiosperm plants.
  Seeds are the product of the ripened ovule, after fertilization by pollen and some growth within the mother plant. The embryo is developed from the zygote and the seed coat from the integuments of the ovule.
  Seeds have been an important development in the reproduction and success of gymnosperm and angiosperm plants, relative to more primitive plants such as ferns, mosses and liverworts, which do not have seeds and use water-dependent means to propagate themselves. Seed plants now dominate biological niches on land, from forests to grasslands both in hot and cold climates.
  The term "seed" also has a general meaning that antedates the above – anything that can be sown, e.g. "seed" potatoes, "seeds" of corn or sunflower "seeds". In the case of sunflower and corn "seeds", what is sown is the seed enclosed in a shell or husk, whereas the potato is a tuber.
  Many structures commonly referred to as "seeds" are actually dry fruits.
context_section_description: Some seeds (e.g., pine) have a wing that aids in wind dispersal.
  The dustlike seeds of orchids are carried efficiently by the wind.
  Some seeds (e.g. milkweed, poplar) have hairs that aid in wind dispersal.
  Other seeds are enclosed in fruit structures that aid wind dispersal in similar ways:
  Dandelion achenes have hairs.
  Maple samaras have two wings.
caption: The seed pod of milkweed (Asclepias syriaca)
exif: {"Image PhotometricInterpretation": "2", "Image Make": "Canon", "Image Model": "Canon EOS-1D Mark II", "Image Orientation": "Horizontal (normal)", "Image XResolution": "350", "Image YResolution": "350", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Digital Photo Professional", "Image DateTime": "2006:10:15 19:13:39", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "236", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "1004", "Thumbnail JPEGInterchangeFormatLength": "4655", "EXIF ExposureTime": "1/400", "EXIF FNumber": "8", "EXIF ExposureProgram": "Aperture Priority", "EXIF ISOSpeedRatings": "200", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2006:10:15 19:13:39", "EXIF DateTimeDigitized": "2006:10:15 19:13:39", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "69/8", "EXIF ApertureValue": "6", "EXIF ExposureBiasValue": "2/3", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "180", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1931", "EXIF ExifImageLength": "2896", "EXIF FocalPlaneXResolution": "220000/71", "EXIF FocalPlaneYResolution": "585500/189", "EXIF FocalPlaneResolutionUnit": "2", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF SceneCaptureType": "Standard"}