These data come from a classic long-term experiment conducted at the East Malling Research Station, Kent, which is the centre four research into apple growing in the U.K. Commercial apple trees consist of two parts grafted together. The lowest part, the rootstock, largely determines the size of the tree, while the upper part (the scion) determines the fruit characteristics. Rootstocks propagated by cuttings (i.e. asexually produced) were once thought to result in smaller trees than those propagated from seeds (i.e. sexually produced). This hypothesis was re-examined in an experiment begun in 1918. Several trees of each type of 16 types of rootstock were planted, all trees having the same scion. Rootstocks I-IX were asexually produced, while X-XVI were sexually produced. In the winter of 1933-4 a number of trees were removed to make room for more, and the data presented here consists of the above ground weights of 104 trees felled in this period. No trees of types VIII, XI or XIV were felled. The description is from Lee (Lee, A.J. Data analysis. An introduction based on R. University of Auckland 1994). The data are from Andrews and Herzberg (1985).
The data consist of a data frame with 104 observations on 3 variables.
| [,1] | Rootstock | factor | levels (I, II, III, IV, IX, V, VI, VII, X, XII, XIII, XV, XVI) |
| [,2] | Weight | integer | . |
| [,3] | Propagated | factor | levels (cutting, seed) |