Thursday, May 8, 2014

Lawns Struggling as Spring Gets Underway by Mary Small

It’s not that unusual for lawns to look a bit tough right now, especially when MotherNature hasn’t been cooperative with moisture! What’s a person to do?
First, try to figure out what is causing the lawn problem.  Look at it as a whole and see if you can pick out a pattern to the damage.

A colleague of mine stood took this picture from her home’s second floor window. You can see that some areas of the lawn are brown and some are green.  The damage is happening in swaths, not small spots or circles. This pattern is pretty typical of poor sprinkler function and it means that the sprinkler system needs a closer look. (Especially note the foreground and the area near the raised bed in the background.)The problem could be that heads are plugged or partially plugged, so aren’t applying enough water. They could be tipped due to the freeze/thaw cycles from winter. Maybe the head is a bit high and was dislodged during aeration or mowing. But you won’t know until you look at the sprinkler heads and check sprinkler delivery.

Tuna cans for measuring water
You can check how much your sprinkler system is applying by using the “catch can” water collection technique as shown in this photo from floridaswater.com. Simply put, set out several similar, straight –sided cans – like tuna – on the lawn and turn on the sprinklers for 10 or 15 minutes. Measure the amount in each can. Is it obvious where sprinklers are applying too much water or not enough? How much are you supposed to apply?
The following fact sheet tells how much water to apply to the lawn and other useful information about lawn watering.   http://www.ext.colostate.edu/pubs/garden/07199.html
This fact sheet shows how to determine and correct turf irrigation system problems, including sprinkler head issues: www.ext.colostate.edu/pubs/crop/04722.html



Here’s another picture of a lawn that is largely brown.  It doesn’t appear to have the brown and green swaths like the previous example. 
This damage is caused by mites, tiny spider like creatures that suck the sap out of grass plants. Turf turns tan-brown and may die; damage is often mistaken for “winter kill.”  Typically mite damage is found on south and west facing exposures and on slopes, the warmer and drier sites of a landscape.  Drought stress is associated with mite populations.
Water applications  in late winter and spring will help limit mite infestations.