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Chapter 2. Recent Changes in Swedish Crop Production

Chapter 2. Recent Changes in Swedish Crop Production

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40



EWERT &?ERG



heavy snow cover. Characteristic of the climate in the middle and

southern parts of the country are short summers with long days and

rather cold and windy winters. In the southernmost provinces in

Sweden the snow cover does not usually stay on the ground very long.

The cold winds can therefore be hard on the overwintering crops. Conditions like the ones just mentioned require an extremely good winter

hardiness in the overwintering plants.

Under the conditions indicated above, there must exist marked differences between temperatures in different parts of the country, ranging from a mean annual temperature of 7 O C. in the southernmost parts

of the country down to -3O C. in the northernmost parts. Although

these temperatures are low, they are still higher than in most countries

at the same latitude. This is due to the Gulf Stream, which brings warm

winds from the Atlantic across the country. These winds warm up

mainly the areas in the south. The mountain ranges on the border between Norway and Sweden prevent the winds from giving northern

Sweden a more genial climate. Differences in climate are, however,

not due merely to the influence of the Gulf Stream. Sweden has a varying topography, and the elevation above sea level has a definite influence on the climate in local areas. Typical plains are found in the

extreme south; across the central part there are lowlands bordering on

the great lakes Vanern, Vattern, Hjalmaren, and Malaren, and along

the coast line and the rivers there are coastal plains and valleys. These

plains, lowlands, and valleys are, however, broken off by mountain

areas and by forested uplands, mixed with small farmland areas. Mountain areas are found primarily in the northern parts of the country,

but the forested uplands are found in most parts of the country except

in the extreme south and along the coast lines. In such areas the climate

is more severe than in the lowlands and the plains, even though they

are located at the same latitude. Consequently there are different climatic conditions for crop production all over the country. This must

be borne in mind when crop production in different districts of the

country is discussed below.

The danger of night frosts during spring and fall confronts the crop

producer with another problem. In southern Sweden late spring frosts

are most likely to cause crop damage, and especially to those which are

now at their northern growing limit. These crops are sensitive to a night

frost after they have emerged. In northern Sweden, on the contrary, the

fall frosts are most dangerous, as they often appear before the cereal

crops are ripe. In the upland areas in different parts of Sweden these

night frosts can occur during every month but July. It occasionally

happens that not even the month of July is free of night frosts. But on



RECENT CHANGES I N SWEDISH CROP PRODUCTION



41



an average it can safely be said that the length of the growing periods,

i.e., periods with a mean temperature of above 3 O C . , is 250 days in

south Sweden, 200 days in the areas just north of Stockholm, and 150

days in northernmost Sweden. One might be tempted to think that the

short growing season in northern Sweden would make it impossible to

cultivate anything but grasses and clovers in those areas. However, long

days may alter the picture. There are, for example, 340 sunshine hours

in the northern coastal area, as against 250 sunshine hours in the

southwestern area.

The average rainfall in Sweden is moderate, in the cultivated areas

varying between 400 and 1000 mm. There are of course some differences between different districts. These are particularly marked in

comparing the western and eastern parts of south and middle Sweden.

I n the western parts there is a heavier rainfall than in the eastern.

This influences the choice of crops, meaning that grasses and clovers

as well as oats are more conmon in the western parts than in

the eastern. Dry spells are rather common in the eastern parts

during late spring and early summer. Such dry spells can cause

poor stands of spring-sown crops. I n the areas where such dry spells

are known to appear, fall-sown crops are used quite extensively in order

to eliminate the disadvantage of spring sowing. They will have a better

chance than have spring-sown crops of coming through the dry periods

during the early part of the growing season. A typical feature of the

distribution per year of the precipitation in Sweden is the fact that the

spring and the early summer generally are quite dry, while the fall is

rather wet. Such a distribution gives neither an ideal growing season

nor a good harvest season.

Apart from depending, to a large extent, on the climate, crop production is highly dependent on the soil. There is a great variation in

soils. Typical are fertile clays, good and poor sandy soils, peat soils

rich in lime as well as in nitrogen, and organic soils poor in nutrients.

The great diversity of soils means that soil drainage, soil management,

and use of fertilizers must be closely studied. This is actually being done

in a very satisfactory way. The questions discussed above were treated

in detail by Osvald (1952).

2. The Present Pattern of Crop Production-Background



The old pattern of crop production, forming the background to those

now prevailing, illustrates in many ways what kinds of crops are

adapted to the climate and soils of Sweden. A good idea of the development can be found in the crop rotations used in different periods of

Swedish agriculture. Crop rotations were introduced about 250 years



42



EWERT ABERG



ago and have since undergone remarkable changes. Before their introduction there were no special plans for crop production. The meadows

were broken up and seeded with cereals during a period of years, i.e.,

as long as these newly broken lands were able to produce a crop. Alternatively, a forested area was cut clean, with the trees left on the ground

to be dried and burned, so that the area after cultivation could be

seeded with cereals or turnips. As in the case of the meadows these

newly cleared areas of forest land were used for the production of crops

as long as possible.

When the land obtained from the meadows or from the forests did

not produce enough, it was left without care, resulting in an abundant

growth of volunteer plants, mostly weeds. As time elapsed this weedy

land was again plowed up and seeded with cereals. It was then discovered that on land where plants with other requirements for nutrients and with a root system different from that of the cereals had

been grown, good cereal yields were obtained. They were markedly

better than the yields on land where cereals had been grown continu'ously. Of course this was due, to some extent, to the plowing under of

the growing plants, their root growth, and the humus enrichment which

they accomplished. There is a similarity between the effect of resting

this open land with resultant volunteer growth of plants and the effect

of the meadows when they were first broken up. This similarity soon

taught the Swedish farmers how to increase production through the use

of rotation systems in which fallow and cereals were the main components or in which temporary leys and cereals alternated. All this was

about 250 years ago. In these rotations the fallow alternated with two,

three, or four years of cereals.

The use of cereals in alternation with established but temporary

clover and grass leys followed. In these rotations cereals were grown

for three to four years and temporary leys for four to ten years. The

temporary ley was plowed up, fallowed, and again seeded to cereals.

This type of rotation became unsatisfactory as the requirements for

high yields per hectare increased. The introduction of balanced crop

rotations was therefore of great importance in the development of

Swedish agriculture. These rotations were greatly influenced by the

Norfolk rotational system: wheat, root crops, spring-sown cereal, and

temporary ley. But the Swedish crop rotations did not, as a rule, develop

into a four-year rotation system similar to the old Norfolk system. Instead they developed into seven-, eight-, nine-, or ten-year rotations.

Typically, the crops were arranged so as to fit both the principles laid

down in the Norfolk rotation and the varying local requirements of crop

production in Sweden. Numerous types of balanced crop rotations have



R E C E N T C H A N G E S I N SWEDISH CR O P PR O D U C TI O N



43



appeared. An example of earlier and less effective ones is: black fallow,

winter wheat or winter rye, three years of a temporary ley, winter

wheat or winter rye, root crops, spring-sown cereal. This rotation appeared to be poor because the temporary ley was undersown in a fallsown cereal and was allowed to remain for a period of three years. The

root crops had a poor place in the rotation, and the second winter

wheat crop had also a poor place, as it followed after the third-year ley.

In this the stand is generally poor and most often consists of grasses and

weeds. A great improvement was a balanced crop rotation of the following type: black fallow, winter wheat or winter rye, root crops, barley, two years of a temporary ley, winter wheat or winter rye, oats.

This rotation is not, however, a very intensive one; it i s rather an

average type of a good balanced crop rotation. As the years went by the

balanced crop rotations became more effective and more adapted to the

local conditions in different parts of the country. This, together with

improvements in the yielding capacity of the cultivated plants through

plant breeding, increased yield per hectare as a result of better soil

drainage, extended use of fertilizers, better soil management, and better

care for the crops during the entire growing season, meant a remarkable development of Swedish crop production during the last 75 to 80

years. This trend, it seems, became more obvious during the last two

decades than at any earlier time.

3 . Developments during the Last Two Decades



The developments during the last two decades are characterized by

changes resulting from the farmers’ lack of understanding of the value

of biological considerations as against their appreciation of technical

and economic considerations. There has been an unwillingness to give

proper weight to some of the biological principles, the earlier recognition of which meant so much to the improvement in crop rotations

and to the rapid increase in Swedish crop production during the latter

part of the 19th and the early part of the 20th centuries. Instead, technical and economic measures, which are so important in the efficient

operation of the farms in present-day farming, are overemphasized.

This change in the attitude of the farmers has resulted in the fact that

crops requiring a great amount of labor have decreased in acreage. A

good example of this is the development of root crop cultivation. T o a

high extent crops are now selected on the basis of the degree of mechanization that they allow. There are now about 107,000 tractors in the

country, whereas there were only about 15,000 in 1939. The combine

harvesters have increased from about 100 in 1939 to about 13,000 in

1954.



44



EWERT ABERG



The recent developments have also been affected by the prices fixed

for different crop products, For instance, when the Swedish Government

wanted an increased production of oil crops during World War I1 and

the years immediately following, they set the prices on rapeseed, white

mustard seed, and seed flax in such a way that increased growing of oil

crops could be expected. The result was as desired: the acreage of oil

crops increased rapidly up to 1951. Such a situation meant that the

farmers did not pay much attention to the biological requirements of

the plants. Oil crops, belonging to the same botanical family, were

grown for one, two, or several years in succession on the same field. The

continued use of the same crop on the same field meant new and increased attacks of parasites. With these followed diminishing yields, and

during the last three years also a decline in acreage of the crops. During

recent years the prices set for cereals have been such that the acreages

of wheat and rye have increased. At the same time the acreage of leys

and pastures has decreased. The latter was the result of a reduction in

the number of cattle following the shift on many farms to farming without cattle. In 1939 there were approximately 3,000,000 head of cattle in

Sweden. Of these 1,920,000 were milk cows. Now there are about

2,500,000, and 1,600,000, respectively. On the other hand, production

per cow is now 3200 kg. milk as against a mere 2650 kg. in 1939. There

is, in other words, no decrease in total milk production in the country,

rather an increase. On one-tenth of the Swedish farms there are no

cattle today.

This development means that there is at present a tendency to increase the acreages of cereals and to decrease the acreages of crops

which, from the biological viewpoint, are suitable for alternation with

the cereals, e.g., root crops, leys, and legumes. I n Table I will be found

some figures which illustrate the trends discussed here. It can be said

that the almost one-hundred-year-old practice of using balanced crop

rotations is gradually being replaced by a practice of an optional crop

order. Such a development must be considered a step forward, as it requires from the Swedish farmers a better knowledge of the properties

of the crops grown. A rotation system with a free order between crops

has good possibilities for growing large areas of crops which for economic reasons, may be desired during certain periods, without lowering

the future productive capacity of the land. But such a rotation system,

if it is going to be effective, calls for farmers who know the resistance

or the susceptibility of different crops to diseases or pests, the ability of

the crops to compete with weeds, the requirements of the crops with

regard to nutrition, temperature, and moisture, and the amount of

labor needed for each crop. As all these factors must be considered in a



TABLE I

Acrcagcs (Thousand Hectares) of Certam Crops in Sweden in Recent Years as Cornpared to the Acreage of thc Same Crops diiring



F d i e r Periods



'



PP:)S ,



'l'1.m-



hcxriq,



purary



culti-



Oil



1cy.q for



vxtcd



h-atilrxl

grass-



crops



hay



Fallow



lands



lands



153



675



414



2n3i



1906



155

133



I159

1379

1345

1348

1352

1519



409

453

194

405

208

184

177

1711

178

176

198

in3



3566

3728

3738

3720

3782

3744

3747

3748

3780

373Q

3733

3733



1421

1127

1000

940

940

940

940

040

9 LO

040

940

940



arid



Fodder

roots



Years



Wheat



Rje



Barley



Ofits



vetches



1876-80



68



366



432



641



53



1906-10

1936-40

1941-45

1946

1947

1948

1049

1950

I961

1952

1953

1954



94

307

280

303

494

316

307

339

328

332

391

433



406

189

309

157

115

160



193

10.2

103

90

100



793



1%



86

94

110

153

190

168



33

25

34

47

46

45

48

43

24

42

2s

46



127

98

146

135

150



nn



657



579

531

529

490

504

502



500

516

506

478



Sugar

brcts



11



d7

81

66



65

61

61

54

50

46

43

-10

34



46

45

53

55

48

48

49

54

54

54

51

59



Potatoes



142

143

144

148

135

1311

131

136

187

123



48

27

45



79

149



1AA

190

148

78

100



1998

1Q75

1261

12'25

1415

1174



Total



46



EWERT



APBERG



system of a free order between crops, adoption of such a system actually

means a definite step forward in Swedish crop production. A free order

of the crops makes possible far better adjustment to the needs for crop

products inside and outside of Sweden than do balanced crop rotations.

This is important now that Sweden is self-sufficient in food production

and derives some revenue by exporting certain farm products.

11. CROPSAND SPECIALMEASURES



1. Wheat

There have been great changes in the acreage of wheat in Sweden

since the beginning of this century, as can be seen from Table I. During

the period 1936 to 1940 about three times as much wheat was grown



,L

1876

-80



---------



c

-



-



C



-WHEAl



-SPRING



@



I



1906

-1 0



-



PERIODS OF YEARS



I



I



I



,



1936 1941 1946 1951

-40 -45 -50 . -58

.



FIG.1. Acreage of bread cereals during the period from 1876 to 1954.



annually as 30 years earlier. As can further be seen, wheat was steadily

grown on about 300,000 hectares per year from the period just mentioned up to 1950, when the beginning of another increase in acreage

can be noted. This increase has continued ever since. The reasons for

this development can be found partly in the shift in the Swedish diet

from rye bread to wheat bread. The figures in Table I clearly show a

decreasing acreage of rye. Thus the rye acreage during the period 1936

to 1940 was only half of that during the period 1906 to 1910. But this

is not the only reason. As will be seen later, additional reasons must be

sought in the crop production figures.

The figures for wheat in Table I are the combined total acreages

of winter wheat and spring wheat. The relationship between these two

wheats is, however, not constant. It is characterized rather by a certain

change from winter wheats to spring wheats (Fig. 1 ) . It means, for



RECENT CHANGES I N S W E D I S H CROP PRODUCTION



47



example, that during the period 1906 to 1910 there were 85,648 hectares

winter wheat and 5931 hectares spring wheat; in 1936 to 1940 the

figures were 231,297 and 75,644, respectively, and in 1953 they were

190,197 and 200,318. The yields from these acreages have been considerable during the last two decades. Thus the total yields of wheat per

year were 672,812 tons during the period 1936 to 1940,491,656 tons in

1941 to 1945 and 643,896 tons in 1946 to 1950. I n 1951, 477,330 tons

were harvested; in 1952, 782,290 tons; and in 1953,996,160 tons. There

has been recently therefore a substantial increase in total yield. The

figures can, for example, be compared with those from the period 1906

to 1910, a mere 190,657 tons, or with the yields in the latter part of the

19th century, which varied between 90,000 and 100,000 tons. The

yields per hectare show, even better than the total yield figures, the increase in production that has resulted from the adoption of newer practices. During the last two decades the yields of winter wheat per hectare

for the country as a whole were 28 per cent higher than they had been

during the period 1906 to 1910, and 50 per cent higher than during the

period 1876 to 1880. For spring wheat the corresponding figures are 18

and 19 per cent, respectively.

The figures given above raise questions as to what are the changes

in production practices and the achievements in crop production and

crop breeding that are responsible for the results obtained. It should

then be remembered that crop rotations and soil management and

fertilizers were little understood in earlier days. Not until the period

from the middle of the 19th century to the beginning of the 20th, when

balanced crop rotations were first used, were these factors considered.

Regular use of complete fertilizers according to definite plans for different crops dates back only two or three decades. The methods of using

fertilizers are still being improved. The assignment of wheat to

such a place in the rotation that it can take advantage of the fertility of

the soil, develop well, and compete successfully with the weeds is not

very much older. Soil drainage, in order to give conditions for good soil

management, became an important factor in the production of wheat

during the last two or three decades. Adding to this the increased use of

high-quality seed and of seed disinfectants, the picture of those factors

that are of importance in the production of wheat becomes even

clearer. The value of high-quality seed is well known to the farmers

producing wheat. Seed disinfectants are at present used by practically

every farmer, as are chemicals against weeds, diseases, and insects. It

is very difficult to find out the share each one of these production factors has had in the yield increase. h e r m a n (1946) analyzed the

reasons for the yield increase in wheat during the period from 1885 to



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