Species suggestions: what else could go here

When a species raises a finding, the question is usually "well, what should go there instead?". Airship will answer it — by testing real candidates at that exact spot rather than by consulting a list.

what else? — alternatives for a flagged plant

Any finding that names a species carries a what else? link. Click it and up to five alternatives appear under that finding, each with up to three plain-English reasons.

What makes a candidate eligible is the part worth understanding: Airship puts that species at that spot and runs the twenty planting checks again. A candidate is only offered if it comes back clean — no fail, no warning. It is not scored against a rule of thumb and it is not filtered on paper; it is actually tried.

Whether you are offered trees or shrubs follows the plant being replaced: something 4 m or taller at maturity is replaced with trees, anything smaller with shrubs. The species you are replacing is never offered back to you.

When nothing suits, it says so plainly rather than padding the list — and suggests that widening the space, changing the ground, or moving what is already there may be the better answer than another species.

How the five are ordered

Once candidates are clean, they are ranked against each other. The ranking favours UK natives, good pollinator and biodiversity value, a genus not yet used on the scheme, a mature spread that fits the room available, and a sensible match to the site's soil and climate. It counts against a species that would deepen a genus already heavily used, or one already common on the scheme — but only once the scheme has at least ten trees, because diversity is meaningless on a handful.

Filling a woodland

Draw a woodland and Airship picks its species rather than repeating a hard-coded mix. Woodland is held to the UK Forestry Standard's figure — no single species over 65% — and the pool is restricted to natives where the release has enough of them. There is no genus cap: in a native wood, several species of the same genus is normal and right.

That is a different rule from the one used for street and amenity trees, which is the familiar diversity guidance about a town's whole tree population. Applying a street-tree cap to a stand of woodland would force exotics into it for no reason, which is exactly what it used to do.

Hedge mixes

The hedge editor will propose a native mix rather than leaving you to assemble one. See Planted hedges and mixes.