Allergy : A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Pollen Calendar

Hickory (Carla)

Refers to any of aproximately 18 species of deciduous trees of the genus Carya and the walnut family ( Juglandaceae ). Most species are native to eastern North America. Hickories often reach 30 m (100 feet) in height. Many species produce edible nuts such as the shagbark hickory ( C. ovata ), the shellbark hickory ( C. laciniosa ), the mockernut hickory ( C. tomentosa ) and the pecan ( C. illinoensis ). [ 1 ]


Walnut ( Juglans)

Arizona Walnut
Juglans major
Image source : [ 2 ]

Refers to about 20 species of deciduous trees of the genus Juglans and family Juglandaceae . Both the black walnut ( J. nigra ), native to eastern North America and the English, or Persian, walnut ( J. regia ), which is native to Iran, are valuable for their timber and edible nuts. The butternut ( J. cinerea ), native to eastern North America also produces an edible nut. [ 1 ]



[1] The Encyclopaedia Britannica Online :
[2] Martin, Paul S., and Drew, Charles M., 1969. "Scanning electron photomicrographs of southwestern pollen grains."
    Journal Arizona Academy of Sciences 5 ( 3 ): 147 - 176. Palynology, University of Arizona :


About us

Site map




Contact Last modified: Fri Jun 28 2002