Calculate Risk of Alfalfa Winter Injury

 

Point Value

Your Score

1. What is your stand age?

 

  • > 3 yrs
  • 2-3 yrs
  • < 1
  • 4
  • 2
  • 1

_________

2. Describe your alfalfa variety:

 

A. What is the Winterhardiness?

  • Adequate winter survival (score 4)
  • Good winter survival (score 3)
  • Very good winter survival (score 2)
  • 3
  • 2
  • 1

Score= ______

 

B. What is it disease resistance?

  • Moderate resistance to only bacterial wilt
  • Moderate or higher resistance to bacterial wilt plus either Phytophthora Root Rot, Fusarium wilt or Verticillium wilt
  • Moderate or higher resistance to all above mentioned diseases
  • 4
  • 3
  • 1

Score= _____

 


Alfalfa variety total score (multiply a. x b.)

________

3. What is your soil pH?

 

  • <6.0
  • 6.1-6.5
  • 6.6 or greater
  • 4
  • 2
  • 0

________

4. What is your soil exchangeable K level?

 

  • Low (
  • Medium (80-120ppm)
  • Optimum (120-160ppm)
  • High (>160ppm)
  • 4
  • 3
  • 1
  • 0

________

5. What is your soil drainage?

 

  • Poor (somewhat poorly drained)
  • Medium (well to moderately well drained)
  • Excellent (sandy soils)
  • 3
  • 2
  • 1

________

6. What is your soil moisture during fall/winter?

 

  • medium to dry
  • wet
  • 0
  • 5

________

7. Describe your harvest frequency:

 

 

Cut Interval and Last Cutting Date
<30 days
Sept 1 to Oct 15
After Oct 15
Before Sept

30 to 35 days
Sept 1 to Oct 15
After Oct 15
Before Sept

>35 days
Sept 1 to Oct 15
After Oct 15
Before Sept


<30

  • 5
  • 4
  • 3

30-35

  • 4
  • 2
  • 0

>35

  • 2
  • 0
  • 0

________

8. For a mid-Sept. or Oct. cut, do you leave> 6-inch stubble?

 

  • No
  • Yes
  • 1
  • 0

________


Determine your total score (Sum points from questions 1-8)

________

 

Winter Injury risk:

If you score:

Your risk is:

3-7

low/below average

8-12

moderate/average

13-17

high/above average

>17

very high to dangerous

Dan Undersander
University of Wisconsin

Undersander©2001

 


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