- Hemizonia congesta
Taxobox
name = "Hemizonia congesta"
image_width = 240px
regnum =Plant ae
divisio =Magnoliophyta
classis =Magnoliopsida
subclassis =Asteridae
unranked_ordo =Euasterids II
ordo =Asterales
familia =Asteraceae
subfamilia =Asteroideae
tribus =Heliantheae
genus = "Hemizonia "
species = "H. congesta"
binomial = "Hemizonia congesta"
binomial_authority = DC."Hemizonia congesta" is a species of flowering plant in the daisy family known by the common name hayfield tarweed. It is native to
California andOregon , where it is a common member of the flora in a number of habitats, particularly grasslands and fields. This is a spindly, thin-stemmed annual herb growing erect to 10 to 80 centimeters in height. Like other tarweeds the stem and foliage are glandular and have an odor reminiscent oftar . Most of the long, narrow, pointed leaves are located on the lower portion of the stem below the branching. Theinflorescence s are covered in glandular hairs and hold daisylike flower heads. Each head has a center of yellowish dark-tipped disc florets and a fringe of bright yellow to white ray florets, often with purplish striping on the undersides. The ray florets are toothed or lobed on the tips, with the middle tooth thinner than the others. There are many subspecies which can vary in appearance.External links
* [http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?609,1326,1329 Jepson Manual Treatment]
* [http://plants.usda.gov/java/profile?symbol=HECO7 USDA Plants Profile]
* [http://calphotos.berkeley.edu/cgi/img_query?query_src=photos_index&where-taxon=Hemizonia+congesta Photo gallery]
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