A data set from Oehlert (2000) \emph{A First Course in Design and
Analysis of Experiments}, New York: W. H. Freeman.

Data originally from Scott Smith (personal communication).

Five cycad plants, three fronds per plant.  Three treatments:
water (control), fungal spores, and horticultural oil. 
Response is the average change in number of mealybugs
after 3 days in two 3 cm by 3 cm patches per frond.
Columns are treatment, plant, and average change.