Just erased everything I wrote, because I misunderstood the design, and I'm still not completely clear.   Is this correct: 4 blocks, 4 treatments gives 16 experimental units, each of which has 10 pots.  Now some of the pots are sampled for pH at 4 different dates.  It appears then that some pots would be sampled 2 times and some 3 times (and it may be something other than that).  On top of that, you have 2 seasons.   Let us know if my assumption about the design is correct, and I might be able to come up with an analysis plan.   Steve Denham     ... View more