Anthracnose (fungus –Colletotrichum graminicola): This disease is more likely to occur in Southeast Texas during August on coastal Bermudagrass. Symptoms that occur during cool, wet weather differ from those that occur during warm, dry weather. During cool, wet periods, a basal stem rot may occur. During warm weather, especially the soil is dry and the bermudagrass canopy and atmosphere are wet or very humid, the pathogen readily colonizes older leaves and hastens leaf and tiller senescence. Sometimes, the pathogen causes oblong, reddish-brown leaf lesions. Tiny black fungal structures with erect, minute black spines can often be seen with a hand lens on infected dead leaf and stem tissue.
Rust (fungus – Puccinia cynodontis): Rust is an occasional problem that usually results in little damage. Occasionally, minor diseases become severe when certain factors are right for disease development. When rust occurs on forage bermudagrass, it should be immediately cut for hay or grazed heavily. This will remove the heavy canopy that favors the retention of high humidity. There is no evidence that these rust fungi produce toxins that would be damaging to livestock.
Fading out (fungus – Bipolaris cynodontis and other fungi): Bipolaris, formerly in the genus Helminthosporium, causes a leaf spot and crown, stolon, and root rot. Leaf spots are irregularly shaped and brown to black. Severely infected leaves may appear tan to straw-colored. This condition is most likely to occur when the grass is in a weakened condition due to certain growth requirements not being met. This occurs commonly in coastal Bermudagrass when potassium levels are low in the soil. This is a common problem in the deep, sandy soils of East Texas. To avoid this problem, growers should fertilize properly with a complete fertilizer, avoid overgrazing or ill timed cutting, and prevent the development of thatch at the base of the plant.
Smut (fungus – Ustilago cynodontis): Smut occasionally occurs on common Bermudagrass but is not known to reduce forage production appreciably. It becomes apparent only when plants form seed heads that are colonized by the smut fungus. Control is not required.
Nematodes (nematode – Pratylenchus spp. and other): Common Bermudagrass is considered to be more susceptible to nematode damage than coastal and other improved forage types. If nematode damage limits growth of common Bermudagrass, one should sod with an improved forage type, preferably Coastal. Nematode problems are more likely in sandy loam soils than in soils with high clay content.