Crop Production in the East of Scotland - SASA

Crop Production in the East of Scotlandharvested crops may not be idealchoices because of difficulties inharvesting. The level of yield is high butless consistently obtained than on Class 1land due to the effects of minorlimitations affecting cultivation, cropgrowth or harvesting. [Indeed, cerealyields from Class 2 land can exceedthose from Class 1, owing to superiorwater supply] The limitations include,either singly or in combination, slightworkability or wetness problems, slightlyunfavourable soil structure or texture,moderate slopes or slightly unfavourableclimate. The limitations are alwaysminor in their effect however and land inthe class is highly productive.• Class 3: Land capable of producing amoderate range of crops. Land in thisclass is capable of producing good yieldsof a narrow range of crops, principallycereals and grass, and/or moderateyields of a wider range includingpotatoes, some vegetable crops (e.g.field beans and summer harvestedbrassicae) and oil-seed rape. The degreeof variability between years will begreater than is the case for Classes 1 and2, mainly due to interactions betweenclimate, soil and management factorsaffecting the timing and type ofcultivations, sowing and harvesting. Themoderate limitations require carefulmanagement and include wetness,restrictions to rooting depth,unfavourable structure or texture,strongly sloping ground, slight erosion ora variable climate. The range of soiltypes within the class is greater than forprevious classes.• Class 4: Land capable of producing anarrow range of crops. The land issuitable for enterprises based primarilyon grassland with short arable breaks(e.g. barley, oats, forage crops). Yields ofarable crops are variable due to soil,wetness or climatic factors. Yields ofgrass are often high but difficulties ofproduction or utilisation may beencountered. The moderately-severelevels of limitation restrict the choice ofcrops and demand careful management.The limitations may include moderatelyseverewetness, occasional damagingfloods, shallow or very stony soils,moderately-steep gradients, erosion,moderately-severe climate orinteractions of these which will increasethe level of farming risk.(Descriptions from Bibby et al., 1991, withadditional material in square brackets).It is useful to subdivide Classes 3 and 4 into3 1 , 3 2 , 4 1 and 4 2 , to provide more preciseinformation on the likely proportion ofshort-term grass (leys) in the rotation,which varies from: “short grass leyscommon” (3 1 ) to “primarily grassland withsome potential for other crops” (4 2 ).Only 0.2% (4,100 ha) of the arable land ofScotland is of Class 1, located along thenorth west coast of East Lothian, and inone continuous block of 1700 ha to thenorth of Carnoustie in Tayside (Angus),known locally as “the golden mile”. In theTweed Valley, the Lothians and Tayside,continuous areas of Class 2 land make uparound half of the arable area, and they areassociated with substantial components ofClass 3 1 . At the upper altitudinal limit ofthese areas, there are large fringes of Class3 2 and 4 (see the maps in Brown & Shipley,1982; Walker et al., 1982). Fife and lowlandMoray are mosaics of Classes 2 to 4,reflecting their more complex geologies andtopographies, whereas the potential arableland in Aberdeenshire and the Stirling areais predominantly of Class 3. Over Scotlandas a whole, there are 172,000 ha of Class 228