## setup framework for 2 factors and response variable

fertilizer<- as.factor(rep(1:3, each=12))
soil_type <- as.factor(rep(c(1,2,3), each=4, times = 3))
growth <- c(130, 155, 74, 180, 34, 40, 80, 75, 20, 70, 82, 58, 
          150, 188, 159, 126, 136, 122, 106, 115, 25, 70, 58, 45, 
          138, 110, 168, 160, 174, 120, 150, 139, 96, 104, 82, 60)

y<- data.frame(fertilizer,soil_type,growth)

## apply a linear model

yfit <- lm(growth ~ fertilizer+soil_type+fertilizer*soil_type, y)

## compute the analysis of variance table

anova(yfit)