Just as plant species diversity is vastly simpler in the traditionally designed environment than in the naturally evolved landscape, so are distribution patterns. Plantings may be geometric, reflecting either the geometry of building and urban settings within which they occur or a designer’s wish to form architectonic spaces with plants. Or plantings may be consciously randomised. The latter approach, whilst often considered ‘naturalistic’, is rarely ‘natural’. For example, it may take the form of a single-species tree planting set in either a lawn or an extensive evergreen ground-cover bed, without the structural components of middlestory or edge vegetation.
Where feasible, existing trees, fortunately, are often preserved and incorporated into designed landscapes, sometimes at great expenditure of money and effort. But even in these cases, simplification is typical, with the naturally occurring understory and ground layer plants removed from beneath the trees to be replaced with the ‘cleaner’ look of lawns, mulch beds or single-species groundcover plantings.