Four jumbled up sentences, related to a topic, are given below. Three of them can be put together to form a coherent paragraph. Identify the odd one out.
1. An esparto grass (Lygeum spartum) is found in the steppes of La Mancha and the southeast; the esparto products of Spain, however, come from an associated alfa grass (Stipa tenacissima).
2. Brown forest soils are restricted to humid Galicia and Cantabria.
3. The mountains of the northern Meseta and the Iberian and Baetic cordilleras carry deciduous Portuguese oak; those of the central Pyrenees, the Iberian ranges and the Central Sierras have diverse pine species.
4. Northern Spain has heath and deciduous woodland (oak, beech).