lander.multi.uniformity {agridat} | R Documentation

## Uniformity trials of wheat and chari, 4 years on the same land.

### Description

Uniformity trials of wheat and chari, 4 years on the same land, in India.

### Usage

    data("lander.multi.uniformity")

### Format

A data frame with 780 observations on the following 5 variables.

`row`

  row

`col`

  column

`yield`

  yield, maunds per plot

`year`

  year

`crop`

  crop

### Details

Uniformity trials carried out at Rawalpindi, India. The area consisted of 5 fields (D4,D5,D6,D7,D8), each 5 acres in size. Each of these 5 fields was divided into three sub-divisions A, B, C, by means of two strong bunds each 5 feet wide. These 3 sub-divisions were divided into 5 blocks, each consisting of 13 experimental plots with 14 non-experiment strips 5 feet wide separating the plots from the other. The dimensions of the plot were 207 ft 5 in by 19 ft 1 in.

The same land was used for 4 consecutive crops. The first crop was wheat, followed by chari/sorghum, followed by wheat 2 times.

Field width: 207.42 * 5 plots = 1037.1 feet

Field length: (19.08+5)*39 rows = 939.12 feet

Conclusions: It is evident, therefore, that soil heterogenity as revealed by any one crop cannot be a true index of the subsequent behavior of that area with respect to other crops. Even the same crop raised in different seasons has not shown any constancy as regards soil heterogeneity.

### Source

Lander, P. E. et al. (1938). "Soil Uniformity Trials in the Punjab I." Ind. J. Agr. Sci. 8:271-307.

### References

None

### Examples

    data(lander.multi.uniformity)
    dat <- lander.multi.uniformity

    # Yearly means, similar to Lander table 7
    ## filter(dat) %>% group_by(year) %>% summarise(yld=mean(yield))
    ## 1 1929   18.1
    ## 2 1930   58.3
    ## 3 1931   22.8
    ## 4 1932   14.1

    # heatmaps for all years
    if(require(desplot)){
      dat$year <- factor(dat$year)
      desplot(yield ~ col*row|year, dat,
              flip=TRUE, aspect=(1037.1/939.12),
              main="lander.multi.uniformity")
    }

[Package agridat version 1.16 Index]