 The tree has a broader crown than its siblings', whilst the generally obovate leaves, < 11 cm long by 7 cm wide, are less acuminate at the apex.Like 'Lobel', the tree flushes markedly later than most other elms, and is rarely in full leaf before mid-May.Whilst the resistance of 'Clusius' to Dutch elm disease proved marginally greater than that of its Dutch predecessors, rated 4 out of 5, it has been eclipsed by later developments such as .