Sorghum halepense (L.) Pers.   Poaceae (Grass Family)   Mediterranean Region   Johnson Grass

                                             June Photo

Plant Characteristics:  Tallish perennial; rhizomes heavy, scaly, extensively creeping; stems erect, glabrous, coarse, 5-15 dm. tall; ligules ciliate; blades 1-5 dm. long, 1-2 cm. wide; panicles 1-3 dm. long, purplish, openly branched; spikelets in pairs, 1 sessile and fertile, the other pedicellate, sterile but well developed, usually male; fertile spikelets 5 mm. long, with pubescent glumes; lemma 4-5 mm. long; awn 1 cm. long, deciduous; sessile spikelet 4-6.5 mm., generally open, 10-60 cm., 5-25 cm. wide.

Habitat:  Common in low wet places, almost wherever irrigation water overflows, as at orchard edges, etc.  May-August.

Name:  Sorgo, the Italian name.  (Munz, Flora So. Calif. 1000).  New Latin, halepensis, of or belonging to Aleppo, (Jaeger 115). Aleppo is a city of n.w. Syria. 

General:  Uncommon in the study area.  The photographed specimen was in the Delhi Ditch.  (my comments).      One of the major noxious weeds in Calif.  As a weed Johnson Grass is scattered in a number of ways:  As an impurity in commercial seed; in manure, as it is known to pass unharmed through the digestive tract of an animal; in irrigation water and by means of cultivating implements, which drag the broken rootstocks from one part of a field to another, or from field to field.  In many sections, Johnson Grass has taken over large agricultural areas to such an extent that their abandonment became necessary.  Under certain conditions, Johnson Grass is poisonous to livestock.  The toxic substance is hydrocyanic acid, which may be present in all parts of the plant.  Young plants are more toxic than mature ones.  (Robbins et al. 109).      Sorghum species have been known to cause hay fever and asthma.  (Fuller 383).      S. halepense has been found to accumulate free nitrates in quantities capable of causing death or distress in cattle.  (Fuller 386).     About 35 species of Old World, some widely cultivated.  (Munz, Flora So. Calif. 1000).

Text Ref:  Hickman, Ed. 1296; Munz, Flora So. Calif. 1000; Robbins et al. 109.

Photo Ref:  May-June 85 # 12,13,14.

Identity: by R. De Ruff, confirmed by F. Roberts.

Computer Ref:  Plant Data 100.

Have plant specimen.

Last edit 5/2/03.                  

                            June Photo                                                      June Photo