Emex spinosa (L.) Campd.

                                                                                                                      Polygonaceae (Buckwheat Family)

                                                                                                                   Mediterranean Region

                      

Devil’s Thorn  

                              March Photo

 

Plant Characteristics:  Glabrous, monoecious annual, plants decumbent to ascending, the stems 3-8 dm. long; lvs. alternate, oblong-ovate to somewhat triangular, with scarious sheathing stipules, 5-12 cm. long, on somewhat shorter to longer petioles;  fls. small, in axillary fascicules or in racemelike terminal infl.; staminate fls. sessile and below; pistillate on jointed pedicels and above; staminate fls. with 5-6 parted calyx,  with narrow segms.; stamens 4-6; pistillate calyx urn-shaped with ovoid tube and 6 lobes in 2 series; ovary 3-angled; styles 3, short; fruiting calyx hard, 3-or 6 angled, burlike, the outer segms. spine tipped, 5-6 mm. long, the inner erect, 6-7 mm. long; aks. 3-angled, enclosed by the spiny perianth, shining, light brown, ca. 4 mm. long.

 

Habitat: Weed in orchards, etc., Ventura Co. to San Diego Co.; native of Mediterranean region.  July-Nov.

 

Name:  Latin, ex, out of, and Rumex, having been transferred from that genus.  (Munz, Flora So. Calif. 676).  Latin, spinatus, with spines.  Referring to the 3-pointed perianth that nearly encloses the fruit.  (my comment).

 

General:  Rare in the study area having been found only once and this along the lower path between Delhi and 23rd St.; more specifically, southerly of the stand of willows and Arundo that grow about half way between the two places.  There were several plants at this single location.  (my comments).       Uncommon noxious weed. (Hickman, Ed. 860).

 

Text Ref:  Abrams, Vol. II 49; Munz, Flora So. Calif. 676; Hickman, Ed. 860.

Photo Ref: Oct 02-Mar 03 # 24, 24A; Mar 03 # 1.

Identity: by R. De Ruff, confirmed by John Johnson.

 

Computer Ref: Plant Data 542.

Have plant specimen.

Last edit 8/7/03.

 

                                  March Photo                                                            March Photo