Slide Presentation

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AUTHOR
Theodore M. Webster
USDA-ARS
Tifton, GA

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TABLE OF CONTENTS
  1. Identification of Tropical Spiderwort (AKA Benghal Dayflower)
  2. Coteledonary stalk - links seed to meristem
  3. Relative to other dayflowers, tropical spiderwort has broad, short leaves
  4. Two-leaf seedlings
  5. Of the 170 Commelina spp., it is one of a few that is vegetatively distinct
  6. Tropical Spiderwort vs. Spreading Dayflower
  7. Red hairs at the apex of the membranous sheath
  8. Dayflower/Spiderwort Flowers
  9. Fused Conical Spathe: Important Identifying Characteristic
  10. Asiatic Dayflower vs. Tropical Spiderwort
  11. Only Dayflower species in the US to have underground flowers
  12. Underground flowers
  13. Key Characteristics for Tropical Spiderwort Identification
  14. Contact Information



SLIDE CONTENTS
  1. Identification of Tropical Spiderwort (AKA Benghal Dayflower) Theodore M. Webster USDA-ARS, Tifton Twebster@tifton.usda.gov
  2. Eric Prostko, UGA Coteledonary stalk – links seed to meristem (common in Commelinaceae)
  3. Photo by Stanley Culpepper, UGA Relative to other dayflowers, tropical spiderwort has broad, short leaves
  4. Leaf Length: Leaf Width ~ 1.5 (Less than 3:1) Alan York, NCSU Of the 170 Commelina spp., it is one of a few that is vegetatively distinct (Faden 1992)
  5. TROPICAL SPIDERWORT Tip more blunted L:W Ratio <3:1 SPREADING DAYFLOWER Tip sharper L:W Ratio >4:1 Mike Burton, NCSU 4.3 1.0 1.5 1.0 MARSH DAYFLOWER L:W Ratio ~ 6:1
  6. Red Hairs at the apex of the membranous sheath Herb Pilcher, USDA-ARS
  7. Dayflower/Spiderwort Flowers (Commelina spp.) Asiatic Dayflower Spreading Dayflower Tropical spiderwort From SWSS Weed ID Guide From SWSS Weed ID Guide This slide is a bit deceiving, as tropical spiderwort flowers are much smaller than its two dayflower relatives Herb Pilcher, USDA-ARS 3 blue petals Upper 2 petals blue Lower petal white
  8. Fused Conical Spathe: Important Identifying Characteristic! Mike Burton, NCSU Top View: Spreading Dayflower Side View: Spreading Dayflower
  9. Fused Not Fused Asiatic Dayflower Tropical Spiderwort
  10. Of the nearly 250,000 species of flowering plants… … 36 have underground flowers Herb Pilcher, USDA-ARS Only dayflower species in the U.S. to have underground flowers
  11. Underground flowers 2002 Arlene Mendoza North Carolina State University
  12. Key Characteristics for Tropical Spiderwort Identification Leaf Length to Leaf Width Ratio <3:1; other dayflowers are 4:1 or greater Underground flowers – unique among dayflowers in the US Aerial flowers are much smaller than other dayflowers; 2 upper petals blue, lower one white Red (or white) hairs at the apex of the sheath that surrounds the stem
  13. Contact Information Twebster@tifton.usda.gov