Q. See if you can figure out what’s happening to our
lawn. It is dying. I’m very bad with technology so I’ll have to send each
picture in separate emails.
lawn. It is dying. I’m very bad with technology so I’ll have to send each
picture in separate emails.
A. First of all, you did a very good job with the
pictures. They all came through just fine.
pictures. They all came through just fine.
 |
| Dying lawn from unidentified causes. |
It is very difficult to determine a problem with the lawn
from pictures. Lawn problems basically boil down to three types; disease,
irrigation or insect problems. Sometimes it can be a combination of these.
The
pictures make me lean towards a disease problem. The first picture you sent had
a combination of two grasses in it; tall fescue and there was a patch of what I
think was ryegrass in the center of the picture. In that picture, the problem
only affected the tall fescue and not the ryegrass.
pictures make me lean towards a disease problem. The first picture you sent had
a combination of two grasses in it; tall fescue and there was a patch of what I
think was ryegrass in the center of the picture. In that picture, the problem
only affected the tall fescue and not the ryegrass.
 |
| The lawn has a color difference that you can see which is actually due to a difference in “texture” more than color. Different grasses have different “textures” due to the reflection of light on the leaf surface. This textural difference is a good indicator that more than one type of grass is present in “patches” and not mixed together. |
Lawns
dying because of irrigation usually die in a specific pattern related to the
irrigation sprinkler heads. Sometimes this pattern can be in between irrigation
sprinkler heads and sometimes the pattern can be close to irrigation sprinkler
heads. It depends on a number of factors including the nozzles that are used,
operating pressure of the system and the design of the system.
Homeowners
that design their own irrigation system usually tell me it’s not due to design
because they “did it themselves”. Good irrigation design is not
something that most people can do. It is much more complicated than people
realize.
that design their own irrigation system usually tell me it’s not due to design
because they “did it themselves”. Good irrigation design is not
something that most people can do. It is much more complicated than people
realize.
 |
| Not the lawn in question. Grass suffering from drought will grass near the damaged area with a darker appearance than the rest of the lawn. This is because blades of grass either “roll” or “fold” in response to a lack of water and cause this darker appearance during times of drought. |
There
are many landscape contractors who are skilled at irrigation design or they
purchase the materials they need from companies that provide for them a professional
irrigation design. Fly-by-nighters will not be skilled in this area.
are many landscape contractors who are skilled at irrigation design or they
purchase the materials they need from companies that provide for them a professional
irrigation design. Fly-by-nighters will not be skilled in this area.
Poor
irrigation coverage or management will contribute to disease problems and
lawns. It is imperative that a good looking lawn has an irrigation system that
is designed and installed by professionals.
irrigation coverage or management will contribute to disease problems and
lawns. It is imperative that a good looking lawn has an irrigation system that
is designed and installed by professionals.
Poor
irrigation management will contribute to disease problems. Never irrigate a
lawn if there is more than three hours of darkness after the irrigation has
been completed. A wet lawn sitting in darkness for more than four or five hours
when temperatures are above 80° F has a very high probability of becoming
diseased. In other words, “Never put a lawn to bed wet.”
irrigation management will contribute to disease problems. Never irrigate a
lawn if there is more than three hours of darkness after the irrigation has
been completed. A wet lawn sitting in darkness for more than four or five hours
when temperatures are above 80° F has a very high probability of becoming
diseased. In other words, “Never put a lawn to bed wet.”
I was
not in town in September and I understand there was a long period of wet
weather and warm temperatures. When I heard this, I was thinking this was an
ideal condition for disease development in lawns.
not in town in September and I understand there was a long period of wet
weather and warm temperatures. When I heard this, I was thinking this was an
ideal condition for disease development in lawns.
Disease
problems may develop in a pattern or they may not. It really depends on the
disease and to a lesser degree the management decisions applied to the lawn.
Judging from the pictures you sent and what I have seen historically here I
lean more towards a disease problem.
problems may develop in a pattern or they may not. It really depends on the
disease and to a lesser degree the management decisions applied to the lawn.
Judging from the pictures you sent and what I have seen historically here I
lean more towards a disease problem.
 |
| Diseases in lawns frequently develop some type of “pattern”. Not always but it can be a good indicator that a disease is at work. |
What to
do? Diseases will run their course until there is a change in the weather or
management practices. If this disease problem began during September rains then
the lowering of temperatures and low humidity stopped the disease from
spreading further. It will probably do little good to apply any kind of
fungicide now.
do? Diseases will run their course until there is a change in the weather or
management practices. If this disease problem began during September rains then
the lowering of temperatures and low humidity stopped the disease from
spreading further. It will probably do little good to apply any kind of
fungicide now.
We are
getting to the tail end of the lawn planting season. I would make a decision to
either replant the lawn from seed or sod but you should get it done by the
middle of November at the latest.
getting to the tail end of the lawn planting season. I would make a decision to
either replant the lawn from seed or sod but you should get it done by the
middle of November at the latest.
If you
decide to re-plant from seed then mow the areas that are dead as short as
possible and rake or power rake these areas until you see bare soil. Seed these
areas with a good quality lawn grass. If your lawn is predominantly tall
fescue, then select a good tall fescue blend and don’t use a cheap one. If you
are going to lay sod in these dead areas, rent a sod cutter and lay some new
sod in these spots.
decide to re-plant from seed then mow the areas that are dead as short as
possible and rake or power rake these areas until you see bare soil. Seed these
areas with a good quality lawn grass. If your lawn is predominantly tall
fescue, then select a good tall fescue blend and don’t use a cheap one. If you
are going to lay sod in these dead areas, rent a sod cutter and lay some new
sod in these spots.