1. Identify Cotyledonary Nodes
   Ex.: Nodes = 0
2. Count total mainstem nodes
   Cotyledonary Nodes = 0
   top (last) node has an attached leaf 1 inch diameter or greater (about quarter size)
   Ex.: Total Nodes = 14
3. Measure plant height (inches)
   Cotyledonary nodes to terminal
4. Calculate height to node ratio (HNR)
   

   Example:	Height = 17 inches
   	Nodes = 14
   	HNR = 17/14 = 1.2

5. Refer to UA Baselines
   • for stage of growth
   • Heat Units After Planting (HUAP 86/55^o F)

   

   

   

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