ABSTRACT
Some authorities consider the earlier taxonomic treatment which placed Tilia in its own family, Tiliaceae, should be retained. This genus comprises about 23 species of deciduous trees having some subspecies and hybrids rarely seen in cultivation. Recognition of the value of clonal rootstocks in producing uniform grades of high-quality trees prompted work in the mid-1980s on this aspect at East Malling Research Station. Apart from well-established combinations involving the major species, Tilia represents a genus with many unresolved problems of incompatibility. Use of Tilia seedling rootstocks may cause problems because batches of seedlings labelled T. cordata or T. platyphyllos, particularly the latter, may contain a substantial percentage of the natural hybrid Tilia x europea. The rootstock is headed back to just below the hypocotyl and the root exposed and grafted using a wedge or short tongue apical veneer.
