Nitrogen Use Efficiency, Nitrogen Fertilizers, NUE, Nitrogen and the EnvironmentPhysiological Feekes Growth Stages in Winter Wheat
Feekes Growth Stages, Feekes Stages

According to Large (1954) cereals develop as follow Feekes Growth Stages

Stage            
T I L L E R I N G
   1            One shoot (number of leaves can be added) = "brairding"
   2            Beginning of tillering
   3            Tillers formed, leaves often twisted spirally. In some varieties of winter wheats,
                   plants may be "creeping" or prostrate
   4            Beginning of the erection of the pseudo-stem, leaf sheaths beginning to lengthen
   5            Pseudo-stem (formed by sheaths of leaves) strongly erected

S T E M    E X T E N S I O N
   6            First node of stem visible at base of shoot
   7            Second node of stem formed, next-to-last leaf just visible
   8            Last leaf visible, but still rolled up, ear beginning to swell
   9            Ligule of last leaf just visible
  10          Sheath of last leaf completely grown out, ear swollen but not yet visible

H E A D I N G
10.1          First ears just visible (awns just showing in barley, ear escaping through split of sheath
                  in wheat or oats)
10.2          Quarter of heading process completed
10.3          Half of heading process completed
10.4          Three-quarters of heading process completed
10.5          All ears out of sheath

F L O W E R I N G  (WHEAT)
10.5.1       Beginning of flowering (wheat)
10.5.2       Flowering complete to top of ear
10.5.3       Flowering over at base of ear
10.5.4       Flowering over, kernel watery ripe

R I P E N I N G
11.1          Milky ripe
11.2          Mealy ripe, contents of kernel soft but dry
11.3          Kernel hard (difficult to divide by thumb-nail)
11.4          Ripe for cutting. Straw dead

 

Reference

Large, E.C. 1954. Growth stages in cereals. Plant Pathol. 3:128-129.

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