The many changes in pear orchard design over the years are largely due to the use of rootstocks of differing vigour and to the pear\u2019s malleability, i.e., the fact that the tree lends itself to various training systems. These factors have enabled growers to develop orchard training systems for planting densities ranging from 1,000 up to 12,000 trees/ha. It should be noted that despite their indubitable advantages as compared to seedling, quince stocks also have a down side. For example, it is often the case that orchards planted in marginal areas soon become unprofitable because the rising densities and the management practices needed for early cropping drive overhead too high. Many training systems are suitable to increase planting density, especially the V and vertical axis systems. New ideas regarding tree shape include plants with 2 or 4 axes so as to divide the vigour over more branches. Nurseries can provide pre-formed trees with two axes ready to be planted or, alternatively, knip the trees for spindle. In pear a very intensive pruning can enhance fruit set of such cultivars as \u2018Abb\ue9 F\ue9tel\u2019, \u2018Doyenne du Comice\u2019 and \u2018Passe Crassane\u2019. There are five cropping models for the most popular pear cultivars and each must be accompanied by an appropriate pruning regime. Pruning regimes for HDP and VHDP designs now incorporate a number of innovations to upgrade tree governance, and \u2018Abb\ue9 F\ue9tel\u2019, the only cultivar whose growth-yield habit and economics make it the best suited to plantings over 4,000 trees/ha, has
been the main beneficiary. This and other issues have led to a certain confusion among growers, which is heightened by the fact that there is little experimental data supporting or refuting the economic viability of such densities and the management practices underpinning them. New quince stocks with vigour similar to quince C are the East Malling selection QR193-16, marketed as MH, and Adams. The most important stocks for LDPs are seedlings. The clonal seedlings from the OH
7F series include especially interesting genotypes like OH
7F40 (Farold\uae40)
