Common lawn problems

A healthy, well-tended lawn will be resistant to many ills, particularly if disease-resistant varieties are used. It also pays to plant a mixture of grasses instead of just one strain. The lawn will thus show less damage should one strain succumb.  Here are a few pests and diseases that could affect your healthy grass:

1.  Chinch bugs. Keep lawns well-watered. Apply insecticidal soap as a soil drench. Grubs chew roots off grass plants; grass is yellowed and often can be rolled up like carpet. Moles and skunks damage lawns, but eat grubs.  Once grubs are controlled, moles and skunks will go elsewhere.
2.  Grubs (larvae of chafers, Asiatic, and June beetles). Drench the area with insecticidal soap or apply beneficial nematodes. Holes in leaves; chewed shoots; some entire plants destroyed.
3. Armyworms, cutworms, or sod webworms. Spray with insecticidal soap. Large heaps of loose soil; tunnels under turf.
4. Moles. Use mole trap, or place smoke pellets in runs. Control grubs. Large holes dug in lawn in late summer or fall.
5. Skunks. Fill holes. Control grubs that skunks are digging for.
6. Slippery gelatinous layer develops over grass. Caused by Algae or gelatinous lichens(slime moulds). Drain and aerate soil. Apply copper sulphate (5 ml or 1 rounded tsp to 40 L of water). Top-dress with compost.Leaf blades with orange-red spots on pustules. Leaves often pale yellow.
7. Bluegrass rust (fungus). Fertilize. Water only in mornings. Overseed with a resistant variety.In summer, very dark green circular areas appear on lawn. Later, these areas turn lighter in colour; small mushrooms appear.
8. Fairy ring (mushrooms)(fungus). Seldom serious. Fungus feeds on decaying wood in soil. Ring expands and will eventually go. If several rings, water with mix of 10-15 ml (2–3 tsp) of copper sulphate in 40 L of water. Patches of yellow, dying grass, which later become brown or covered with cottony white mould. Often seen after long-lasting snow cover has melted or when nitrogen has been applied later than August.
9. Fusarium snow mould (fungus). Keep lawn mowed short in fall. In spring, break up snow mould webs with a fan rake. Spray with copper if serious. Small straw-coloured spots on lawn. Later, large crusty mats. Mats can suffocate and kill grass. Fungus may develop when snow cover is more than 10 cm/4 in deep; shows up as snow melts.
10. Gray snow mould (Typhula)(fungus). Break up crusty masses with rake. Spray with copper if raking does not control. Long grass is more likely to be attacked. Oval to round brown spots on foliage, especially in spring and fall.
11. Leaf spots (melting out)(fungus). Spray with fish emulsion. Occurs mainly on Kentucky bluegrass; use 'Merion' variety instead. Leaves show white powdery deposit during periods of high humidity in summer.
12. Powdery mildew (fungus). Generally disappears with the return of cooler weather. Spray with baking soda.Pink or reddish gelatinous growths, particularly on fine-leaved grassesin coastal regions.
13. Red thread (fungus). Aerate lawn and plant varieties such as 'Eclipse'. Improve drainage if problem occurs frequently. Black stripes of fungal spores split grass blades open.
14. Striped smut (fungus). Difficult to control. If severe, kill grass and re-seed with a resistant strain.