As any gardener knows many garden plants are prone to disease. Gardens can be a great place to find pathogens, both on cultivated plants and weeds. For pathogens on weeds look at the page on urban pathogens.
Symptoms on a leaf — look for withered, greyish leaf tips.
Up close the white tufts of conidia are visible.
Conidia under high magnification. Unfortunately this is from before I got good at microscopy!
Common on the host in parks and gardens. Look for withered leaf tips on which are found tiny white conidia in tufts.
European distribution of Ramularia septata via GBIF.
Mahonia Berberis aquifolium
Mahonia rust Cumminsiella mirabillisima
Teliospores under ×400 magnification.
Very common on the host in gardens. Brown telia and uredinia are formed on the underside of the leaf, with red discolouration around them. It also sometimes forms orange aecia.
European distribution of Cumminsiella mirabilissima via GBIF.
Snowberry Symphoricarpos albus
Snowberry Powdery Mildew Erysiphe symphoricarpi
Extremely common on the host in gardens. Look for thin white patches on the leaves, sometimes distorting them slightly.
European distribution of Erysiphe symphoricarpi via GBIF.
