Uniformity trials of wheat and chari, 4 years on the same land.
lander.multi.uniformity.Rd
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
Note, "chari" in this paper is Andropogon Sorghum, and "wheat" is Triticum vulgare.
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.
Examples
if (FALSE) { # \dontrun{
library(agridat)
data(lander.multi.uniformity)
dat <- lander.multi.uniformity
# Yearly means, similar to Lander table 7
## filter(dat)
## 1 1929 18.1
## 2 1930 58.3
## 3 1931 22.8
## 4 1932 14.1
# heatmaps for all years
libs(desplot)
dat$year <- factor(dat$year)
desplot(dat, yield ~ col*row|year,
flip=TRUE, aspect=(1037.1/939.12),
main="lander.multi.uniformity")
} # }