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% to consider. Once that target DM% is identified consider varieties within 2% either side being within five days either side of the selected harvest date e.g. the target DM% is 35 then consider a range between 33-37 which represents a 10 day window. 

Identifying the correct DM% range:

  1. In Table A - select the conditions which apply to the proposed crop and enter the DM% score in the end column.
  2. Select the regional score from Table B, insert them in Table A and add up to total.
  3. Once the target DM% range has been identified refer to 'choosing a variety list' below

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

Table A
Harvest date 15-22 Sept 23-30 Sept 1-7 Oct 8-15 Oct SCORE
DM% 6 4 2 0  
Sowing date 15-22 Apr 23-30 Apr 1-7 May 7-15 May  
DM% 0 1 2 3  
Altitude 0-5 m 50-100 m 100-150 m +150 m  
DM% 0 1 2 3  
Soil type Light Medium Heavy Very heavy  
DM% 0 1 2 3  
Rainfall Low (10-27") Medium (28-39") High (40+")    
DM% 0 1 2    
      Regional score From Table B  

Table B - allocating regional points
Regional area Dry matter score
Scotland and Northumberland 32
Northern England (Borders to Nottinghamshire) 30
North Midlands (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


Choosing a variety list

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.