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:
- In Table A - select the conditions which apply to the proposed crop and enter the DM% score in the end column.
- Select the regional score from Table B, insert them in Table A and add up to total.
- 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.
|Harvest date||15-22 Sept||23-30 Sept||1-7 Oct||8-15 Oct||SCORE|
|Sowing date||15-22 Apr||23-30 Apr||1-7 May||7-15 May|
|Altitude||0-5 m||50-100 m||100-150 m||+150 m|
|Soil type||Light||Medium||Heavy||Very heavy|
|Rainfall||Low (10-27")||Medium (28-39")||High (40+")|
|Regional score||From Table B|
|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 East and southern counties||24|
|Somerset and Dorset||26|
|North Devon and Cornwall||30|
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.