Breton Plots - Classical Plots

Design period: (1930—)

Design Type

Other

Description

The two rotations were originally a four-year rotation (3 years of cereals and 1 year of legumes) and continuous wheat. In 1938, the four-year rotation was converted to the five-year W-O-B-H-H. In 1941, the continuous wheat rotation was changed to a wheat-fallow system. In 1980 the manuring treatments were updated to reflect higher nutrient application rates commonly used for modern cereal varieties.

Design description

The experiment has 6 series (labelled A-F), each split into 11 plots (labelled 1-11 for each series) for the 11 different manuring treatments. Series A, B, C, D and F carried the W-O-B-H-H rotation and Series E the W-F rotation.

Number of plots

66

Number of harvests per year

1

Crops

Crop	Years grown
wheat
oats
barley
feed grasses
legumes
cereals
alfalfa
fallow

Crop Rotations

4-year rotation  1930—1938

• 1
  cereals
• 2
  cereals
• 3
  cereals
• 4
  legumes

continuous wheat  1930—1941

• 1
  wheat

W-O-B-H-H  1939—

• 1
  wheat
• 2
  oats
• 3
  barley
• 4
  feed grasses

  Grown for hay. Before 1967 mixtures varied but always included a legume. Since 1967 have been Medicago sativa (alfalfa) and brome mixtures.
• 5
  feed grasses

  Grown for hay. Before 1967 mixtures varied but always included a legume. Since 1967 have been Medicago sativa (alfalfa) and brome mixtures.

W-F  1942—

• 1
  wheat
• 2
  fallow

Factors

Factor name

Factor levels

nitrogen fertilizer exposure

N

Nitrogen fertilizer applied. Amounts vary between crops and rotation phases and range from 11 to 90 kgN/ha.

phosphate fertilizer exposure

P22  (22 kgP/ha)

1980—

P6  (6 kgP/ha)

1930—1979

P9  (9 kgP/ha)

1930—1979

potassium fertilizer exposure

K46  (46 kgK/ha)

1980—

K16  (16 kgK/ha)

1930—1979

farmyard manure exposure

M

Application frequency: Every 5 years

sulfate fertiliser exposure

S8  (8 kgS/ha)

1930—1979

S9  (9 kgS/ha)

1930—1979

S10  (10 kgS/ha)

1930—1979

S11  (11 kgS/ha)

1930—1979

S5.5  (5.5 kgS/ha)

1980—

liming exposure

L

Lime applied. Amounts and timings of lime applied vary between crops and rotation phases.

Factor combinations

Control  1930—

Plots 1, 5 & 11. No manure treatments applied.

Manure(M)  1930—

Plot 2

farmyard manure exposure: M

NPKS  1930—

Plot 3.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P6

potassium fertilizer exposure: K46

sulfate fertiliser exposure: S10

NS  1930—1979

Plot 4.

nitrogen fertilizer exposure: N

sulfate fertiliser exposure: S11

NSK(-P)  1980—

Plot 4.

nitrogen fertilizer exposure: N

potassium fertilizer exposure: K46

sulfate fertiliser exposure: S5.5

L  1930—

Plot 6.

liming exposure: L

LP  1930—1963

Plot 7.

liming exposure: L

phosphate fertilizer exposure: P6

NPKSL  1964—1979

Plot 7.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P6

potassium fertilizer exposure: K16

sulfate fertiliser exposure: S9

liming exposure: L

NPK(-S)  1980—

Plot 7.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P22

potassium fertilizer exposure: K46

P  1930—1979

Plot 8.

phosphate fertilizer exposure: P9

PKS(-N)  1980—

Plot 8.

phosphate fertilizer exposure: P22

potassium fertilizer exposure: K46

sulfate fertiliser exposure: S5.5

MNPS  1930—1979

Plot 9.

farmyard manure exposure: M

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P6

sulfate fertiliser exposure: S8

NPKS  1980—

Plot 9.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P22

potassium fertilizer exposure: K46

sulfate fertiliser exposure: S5.5

NPS  1930—1979

Plot 10.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P6

sulfate fertiliser exposure: S8

NPS-K  1980—

Plot 10.

nitrogen fertilizer exposure: N

phosphate fertilizer exposure: P22

potassium fertilizer exposure: K46

Measurements

Variable	Material	Units	Frequency	Scale	Comment
grain yield trait	Not specified
forage yield	Not specified