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Stark-Billings County |
Extension Spotlites
May 28, 2009
Early Growth Staging Small Grains
Early planted spring wheat and barley have now emerged and are adding some green to the countryside. Winter wheat fields are filling-in nicely. In fact, the more developed winter wheat fields are beyond the 4 to 5 leaf stage and will soon begin jointing. The optimum and/or the legal timing of a number of management practices (i.e. nitrogen, herbicide and fungicide applications) is frequently determined by the growth stage of the crop. Therefore, correctly growth staging a crop is important in the crop management process. Though there are a number of different scales (i.e. Feekes, Haun and Zadok) that have been developed to classify the growth stages of small grains, typically early management recommendations are based on leaf numbers or other visible characteristics of the plant.
When growth staging your crop you should begin by obtaining a representative sample of plants from the field or part of the field of interest. To give you a good feel for an average plant, use ten plants selected at random away from the edges of the field. Remove any soil attached to the plant so that you are able to observe the roots and crown. Leaf stage is the most common physical feature used to describe early development of small grain crops. Leaf stage is defined by the number of leaves that have visible collars on the main stem. Care must be taken to ensure that the earliest leaves are included when counting. The first leaf is small and is frequently lost from the plant during normal growth. It has a characteristically blunt tip. Look for the sheath remnants at the crown of the plant if you suspect that the first leaf (or second for that matter) is missing. Count only the leaves on the main stem, which is the tallest and most leafy of the stem. Include only those leaves that have a collar. When staging plants, include all leaves, even those that have been damaged by hail or frost. The total number of leaves that a plant will develop is more or less fixed for a given variety; leaves that are striped from the plant will not be replaced by additional new leaves.
For more information contact:
Kurt Froelich,
Extension Agent
NDSU Extension Service
Stark-Billings County
1340 W. Villard St.
Dickinson ND 58601-4646
(701) 456-7665