Ben wrote:
I find that statement interesting. I'm no expert but I thought that
thatch was still attached the the roots, not clippings. I've been
trying to get an expert opinion on that for years.

The thatch is the dead, fibrous material still attached to the roots, and
often has green tips. It could be a result of a chain of events that
includes clippings, but it's not the clippings, and normal clippings aren't
the cause.

If the lawn isn't mowed often enough, and if when it is mowed too much is
consistently mowed-off at once, those clippings can essentially form a mulch
that'll make it difficult for air and water to get to the soil. Combine that
with frequent, shallow watering, and you'll get shallow roots. The shoots
growing off those shallow roots are more likely to form a layer of dead
thatch.

Putting too much nitrogen fertilizer on the lawn will cause it to grow too
fast, setting-up the whole cycle. With just the decomposed clippings
providing nitrogen on my lawn this year, I've had to mow two -- sometimes
three! -- times a week. And that was with the mower at the highest setting,
I was often finding myself mowing close to 1/3 the height of the grass even
when mowing that often.

I don't have a thatch problem, but my neighbor does. His lawn service spread
fertilizer in mid-spring, and only mowed once a week. And when it was mowed,
it was practically scalped. The only plus was that the service bagged the
clippings. We've gone only about 4 days without rain, and my neighbor's lawn
is already just golden tips on top of a layer of thatch.

So the lawn where the clipping were bagged has a thatch problem. The lawn
where the clippings were left doesn't. Looking at the two lawns makes it
obvious that it's not leaving the clippings that causes thatch problems.
It's a combination of fertilization, and mowing frequency and height.

Once the neighbor starts watering, he'll water for 15 or 20 minutes every
day, so later this year you'll also be able to see how daily shallow
watering vs. weekly deep watering will also affect lawn health. The layer of
thatch on his lawn is only going to make it worse, too. By fall, he'll have
one dead lawn with a few patches of fungal problems, at which point his lawn
service will spray some more crap on his lawn. The fall rains will come, and
by November he'll have a halfway decent looking lawn (if you look fast), and
he'll be convinced that it was whatever the lawn guy sprayed on it at the
end of summer.

I'm not sure how many more times we'll repeat this annual cycle before he
believes me when I tell him that it all started with the fertilizer his
service dumped on the lawn in the spring, or that the biggest factor was the
low, only weekly mowing. Or that his summer solution of shallow watering
didn't help, either. He still hasn't figured out that his lawn looks the
best during the 4 months that his lawn service doesn't touch it each winter.

--
Warren H.

==========
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employer, my friends, nor (as she often tells me) my wife.
Any resemblance to the views of anybody living or dead is
coincidental. No animals were hurt in the writing of this
response -- unless you count my dog who desperately wants
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