data <- scan(what = list(session=0,treat="",plates=0), multi.line=F)
               1    b1-3               19
               1    b1-2               17
               1    b1-1               11
               2    b1-0                6
               2    b2-3               26
               2    b2-2               23
               3    b2-1               21
               3    b2-0               19
               3    ctrl               28
               4    b1-3               20
               4    b1-0                7
               4    b2-1               20
               5    b1-2               17
               5    b2-3               26
               5    b2-0               19
               6    b1-1               15
               6    b2-2               23
               6    ctrl               31
               7    b1-3               20
               7    b2-3               26
               7    ctrl               31
               8    b1-2               16
               8    b2-2               23
               8    b2-1               21
               9    b1-1               13
               9    b1-0                7
               9    b2-0               20
              10    b1-3               20
              10    b2-2               24
              10    b2-0               19
              11    b1-2               17
              11    b1-0                6
              11    ctrl               29
              12    b1-1               14
              12    b2-3               24
              12    b2-1               21

data

oemp14.2 <- data.frame(data)
rm(data)

oemp14.2$session  <- as.factor(oemp14.2$session)
oemp14.2$treat   <- as.factor(oemp14.2$treat)




 # intrablock analysis

oemp14.2.lm          <- lm(plates ~ session + treat, data = oemp14.2)
anova(oemp14.2.lm)


 # check assumptions 

par(mfrow=c(2,2))  
plot(oemp14.2.lm)
par(mfrow=c(1,1))  



 # using the afex package to recover interblock information ;

library(afex)

oemp14.2.afex1  <- mixed(plates ~ (1|session) + treat, data = oemp14.2)

summary(oemp14.2.afex1)

nice(oemp14.2.afex1)

lsmeans(oemp14.2.afex1, ~treat)

 # testing the contrast shown in the text

levels(oemp14.2$treat)

oemp14.2.afex1.lsm <- lsmeans(oemp14.2.afex1, "treat")
oemp14.2.afex1.lsm

Contrasts = list(Base1vsBase2 = c(.25, .25, .25, .25, -.25, -.25, -.25, -.25, 0))

contrast(oemp14.2.afex1.lsm, Contrasts, adjust = "none")