Delphinium ajacis  

Delphinium ajacis L. (syn.: Delphinium ambiguum L., D. gayanum Wilmott, Consolida ajacis (L.) Schur) (C and E-Medit.) – A rather frequent but ephemeral alien, it was first documented in 1854 (Verloove 2006). Delphinium ajacis is introduced intentionally as an ornamental and easily self-seeds where ever planted. As such it is found near gardens, in roadsides, on rough ground, dumps, etc. In addition, it is also a regular impurity in imported cereals and is found in port areas near grain mills (railway sidings, roadsides, unloading quays, etc.).

Delphinium ajacis has often been confused with D. orientale. It is distinguished by its much longer spur (12-18 mm vs. 6-10 mm). Also, its flowers are usually blue (pink or white in cultivars) while they are violet-purplish in D. orientale.

Selected literature:

Blanché C. & Molero J. (1993). Taxonomic and nomenclatural notes on Delphinium L. Botanical Journal of the Linnean Society 113(2): 125-133.
Verloove F. (2006) Catalogue of neophytes in Belgium (1800-2005). Scripta Botanica Belgica 39: 89 p. [available online at: http://alienplantsbelgium.be/sites/alienplantsbelgium.be/files/tabel_2.pdf]