Dr. Phyto

Crested dog's-tail

Cynosurus cristatus

Diseases & pests on this plant

• red thread (lawn disease)Laetisaria fuciformis

  Irregular patches of bleached, straw-pink grass from a few cm to ~25 cm across; close up, tiny coral-pink to red gelatinous threads and branching needles bind the dead leaf tips together — the diagnostic sign; in damp weather a faint pink cotton-wool web may show. Grass is killed only at the leaf, not the root, so the lawn recovers.

• pink snow mouldMicrodochium nivale

  Patches of dead seedlings emerging after snowmelt, pinkish-white fluffy mycelium covering plants in cold humid mornings, surviving plants are stunted with brown crown rot.

• Drought dormancy (lawn)Lawn drought dormancy

  Large, irregular areas of the lawn turn uniformly straw-yellow to tan during hot, dry spells, usually starting on the sunniest, most exposed parts and over sandy or shallow soil. Footprints stay visibly pressed in (loss of springiness), but the crowns at the base of the plants remain alive and the grass greens up again after rain.

• dollar spot (lawn disease)Clarireedia jacksonii

  Small, round, straw-coloured sunken spots about the size of a coin (2–6 cm) that can merge into larger bleached patches; individual grass blades show a light tan lesion with a darker reddish-brown band right across the leaf; in early morning dew a fine white cobwebby mycelium can be seen. Most common on fine turf in warm days with cool dewy nights.

• leatherjackets (crane fly larvae)Tipula paludosa

  Yellowing, thinning and dead patches of lawn that lift easily because the roots have been eaten; greyish-brown, legless, tough-skinned grubs up to ~3 cm ("leatherjackets") are found in the top few cm of soil when you lift a patch; birds, badgers or foxes tear up the turf to feed on them; damage peaks in spring as overwintered larvae feed.

• crown rust of oatPuccinia coronata

  Bright orange-yellow pustules on leaves with characteristic crown-shaped teliospores in late season, severe infection causes premature leaf death + lodging, kernels do not fill properly leading to shrivelled grain, in epidemic years 50%+ yield loss with poor grain quality.