lyon.potato.uniformity {agridat} | R Documentation

## Uniformity trial of potatoes

### Description

Uniformity trial of potatoes at Nebraska Experiment Station, 1909.

### Format

A data frame with 204 observations on the following 3 variables.

`row`

  row

`col`

  column, section

`yield`

  yield, pounds

### Details

In 1909, potatoes were harvested from uniform land at Nebraska Experiment Station.

There were 34 rows, 34 inches apart. Lyon, page 97 says "He harvested each row in six sections, each of which was seventy-two feet and seven inches long." It is not clear if each section is 72 feet long, or if the entire row is 72 feet long. Yield of potato is roughly 0.5 to 0.8 pounds per square foot, so it seems more plausible the entire row is 72 feet long (see calculations below).

Field width: 6 plots = 72 feet

Field length: 34 rows * 34 in / 12in/ft = 96 ft

### Source

Lyon, T.L. (1911). Some experiments to estimate errors in field plat tests. Proc. Amer. Soc. Agron, 3, 89-114. Table III. http://doi.org/10.2134/agronj1911.00021962000300010016x

### References

None.

### Examples

    ## Not run:

      data(lyon.potato.uniformity)
      dat <- lyon.potato.uniformity

      # Yield per square foot, assuming 72 foot rows
      sum(dat$yield)/(72*96) # 0.67 # seems about right
      # Yield per square foot, assuming 72 foot plots
      sum(dat$yield)/(6*72*96) # 0.11

      require(desplot)
      desplot(yield ~ col*row, dat,
              tick=TRUE, flip=TRUE, aspect=96/72, # true aspect
              main="lyon.potato.uniformity")

    ## End(Not run)

[Package agridat version 1.16 Index]