There is a wide array of leaf spots that infect the cultivated strawberry and often wild strawberry species. Some are known as leaf spot (birds-eye leafspot), black leaf spot, Septoria leaf spot, Cercospora leaf spot, Alternaria leaf spot, red spot, and Angular leafspot. These leaf pathogens are caused by several fungi and may occur with other foliar diseases. Usually, disease development is favored by rain and warm, humid weather.

The fungi overwinter on infected plants, plant debris, and weed hosts. In the spring, spores are produced and are discharged by splashing rain into air currents. They then land on and infect new leaves. Lesions or “spots” are more numerous on upper leaf surfaces and appear circular to irregular in shape. Upon observation, these lesions may often have definite reddish purple to rusty brown borders which surround a necrotic area. Lesion size and appearance is often influenced by the host cultivar and the ambient temperature. The leaf spots may or may not cause severe problems, which often depends on the cultivar planted. Susceptible cultivars may be partly or completely defoliated by late summer. In years that are particularly favorable for disease development, they may be severely weakened.

Sanitation and the use of resistant cultivars are advised as well as adequate plant and row spacing and keeping plants out of the shade. The application of protective fungicides at blossom time and before fruiting will give adequate leafspot control.

Angular leaf spot, is caused by the bacterium Xanthomonas fragariae, which causes a water-soaked lesion on the lower leaf surface. Under moist conditions, the bacterium produces an exudate that, when dry, appears as a whitish, scaly film. The pathogen not only infects the foliage but can invade the vascular system of the plant, causing decline. Important commercial cultivars have not been found to exhibit resistance to angular leaf spot. Antibiotics are applied for the control of this disease.