Although Coralroot is not generally acknowledged to be a foodplant in the UK, Orange-tips seem to preferentially utilise it where it is present. Nearby I did not even find larvae (except outside the wood) on Jack-by-the-Hedge (Garlic Mustard), Alliaria petiolata.

26 May. As a cannabilistic species there is at most one larva per plant! Then they proceed to eat the bulbils! The eaten parts are white. Here is a full grown caterpillar, about an inch long.

18th May - Orange-tip larva finishing off Coralroot pods

But can the larvae actually develop on this spindly plant, whose magnificence is gone by late May? The plant later bears up to four rather pathetic green pods, but can also reproduce via the deep purple 'bulbils' which drop off and grow into new plants

In the Spring exuberance of a Chilterns wood, a female Orange-tip has laid her orange egg, near the bottom of the image. The plant is the beautiful Coralroot, Cardamine bulbifera, for which the area is a UK hotspot, for this rare ancient woodland plant.

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