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Free Dry Matter range predictor for forage maize

Choosing the right target DM% for your farm

The following procedure is designed to identify an initial target DM% for you to consider. Once that target DM% is identified consider varieties within 2% either side being within 5 days either side of your selected harvest date e.g. Your target DM% is 35 then consider a range between 33-37 which represents a ten day window.  

Identifying the correct DM% range:

a. In Table A select the conditions which apply to your proposed crop and enter the DM% score in the end column.

b. Select the regional score from Table B and insert them in Table A and add up to total.

c.Once the target DM% range has been identified refer to which list do I use below tables.

Remember that planning for a late harvest date so that you can use higher yielding, lower dry matter varieties, and works in an average season but leaves you less leeway in a bad one.

Table A

Harvest date

15-22 Sept

23-30Sept

1-7Oct

8-15 Oct

SCORE

DM%

6

4

2

0

 

Sowing date

15-22 April

23-30April

1-7May

7-15 May

 

DM%

0

1

2

3

 

Altitude

0-50m

50-100m

100-150m

+150m

 

DM%

0

1

2

3

 

Soil Type

Light

Medium

Heavy

Very Heavy

 

DM%

0

1

2

3

 

Rain Fall

Low

(10”-27”)

Medium

(28”-39”)

High

(40”+)

 

 

DM%

0

1

2

 

 

 

 

 

Regional score

From table B

 

 

 

 

 

Total

 

Table B Allocating points for your region

Regional area

Dry Matter score

Scotland and Northumberland

32

Northern England (Borders to Nottinghamshire)

30

North Midland (Nottinghamshire to Hertfordshire)

28

North and Mid Wales

30

South Midlands, East Anglia and Welsh borders

26

South Wales

28

South East and Southern Counties

24

Somerset and Dorset

26

North Devon and Cornwall

30

South Devon

28

Which Variety List do I use?

 

Favourable DL applies to regions with a rating of 28 or less in Table B.  In these conditions, later maturing varieties may be favoured.

Less Favourable DL applies to regions with a rating of more than 28 in Table B and at other sites where the altitude or other previously mentioned factors necessitate an early maturing variety.