Photo Gallery

Site will be retired 9/1/2026

This site is no longer being developed and will be retired on September 1, 2026. Please contact us if you have any questions or would like to provide support to continue the project.

P. alni in alder forest, Germany, with T. Jung

P. alni in alder forest, Germany, with T. Jung

P. alni canker on gray alder

Grey alder (A. incana) with collar rot caused by P. alni

P. alni oogonia subspecies and variants

Fig. 40. P. alni subsp. uniformis. Fig. 41.  P. alni subsp. multiformis German variant. Fig. 42. P. alni subsp. alni. Fig. 43. 

P. alni symptoms on European Alder

Mature, riparian common alder (A. glutinosa) stand heavily impacted by root and collar rot caused by P. alni

P. alni in riparian alder, Germany

P. alni in riparian alder, Germany

P. alni subsp alni sporangium

Non-papillate, non caducous sporangium, photo used with permission from Q-bank

P. alni oogonium

Bullate oogonium of P. alni (German variant) with oospore and amphigynous antheridium.

P. alni sporangia

Non-papillate sporangia of P. alni showing nested proliferation.

P. alni in riparian alder, Scotland

P. alni in riparian alder, Scotland

P. alni in alder, Illwald, France

P. alni in alder, Illwald, France

P. alni basal canker on European Alder

P. alni basal canker on European Alder (Alnus glutinosa)

P. alni symptoms on European Alder

Mature, riparian common alder (A. glutinosa) stand with high impact of Phytophthora root and collar rot.

Pages