Lawn Update

April 2, 2012

Diseases slow - red thread and leaf spots have slowed down considerably with dryer weather. These fungal diseases could easily reoccur with moderate temperatures and moist conditions. If your area is wet… then these and other diseases may be active and increasing.

Frost damage – At least in central Ohio, there is considerable “tip bleaching” on lawns due to the cold temperatures on March 26. This appears as white or light yellow dieback of the leaf tip and can injury a considerable part of the leaf blade. The condition is often more severe on tall fescue or on turf that has grown taller than the rest of the lawn and when mowed the lower tender leaf blades are exposed. If the mowing was done shortly before the cold temperatures, frost occurs, the damage can be considerable. Also at time the mower tracks can show damage (see photos).

At times bands appear across the leaf blades. Tissue that is in the bud stage is sensitive to cold temperatures and results in damage to the chlorophyll which result in these white or light colored bands across leaf blades.

The crowns of the plants are alive and new growth will occur. However, if the damage has affected most of the leaf, time is needed for the plants to grow out of the injury. Several mowing’s may be required to remove the damaged leaf tissue and for new leaf tissue to grow out and replace the injury. It is recommended to follow good mowing practices:

  1. mow high (2.5 “ – 3.0”)
  2. mow with a sharp blade
  3. mow frequently (To avoid excessive leaf removal, this is quiet challenging in spring since there is often rapid growth.)

Frost injury to tall descue at the bottom of the photo; the Kentucky Bluegrass at the top has less injury.

LowTempInjuryLow temperature injury to lawn.
LowTempInjury2Injured turf from low temperatures and clipping on lawn.
HeavyFrostLawn mowed the day before temperatures went down to 28 degrees F and heavy frost.
TipDamageTip damage to tall fescue due to low temperatures.