tmpar <- par( mar = c(3.1,3.6,0,0), mfrow = c(1,2) )
on.exit( rm( tmp, tmpar, right, margin ) )

margin.plot( brass.wpaov, factors = c("crop","year"), xaxt = "n",
   xlab = "", ylab = "" )
tmp <- par( pty = "s" )
right <- par("usr")[1]
mtext( "margin", 1, 0, at = right )
margin <- seq( 2, 8, 2)
mtext( as.character( margin ), 1, 0, at = margin )
mtext( "crop", 1, 1, at = right )
margin <- precision( lsmean( brass.wpaov, factors = "crop" ) )
mtext( names( margin ), 1, 1, at = uncollide( margin, 0.05 ) )
mtext( "(a) crop by year", 1, 2 )
mtext( "yield in 10000 kg", 2, 2.5 )
par( tmp )
###########################################################################

lsd.plot( brass.spaov, factors = c("pyrrat","crop"),
   xpos = .6, ypos = 3.25, xlab = "", ylab = "" )
mtext( "deviation from mean crop yield", 2, 2.5 )
mtext( "(b) pyr rate by crop", 1, 2 )

par( tmpar )