Question
each spring more moss takes over what was once rich and thick grass.  how do i get rid of it?

Answer
Hi Rich,

Sounds like you have a situation of increasing shade with aging trees,...but you did not mention this important factor directly.


ABOUT MOSS PROBLEMS:
Where conditions are favorable for turf-grasses,...moss will usually find it impossible to grow.  For this reason, having moss in the landscape is either a 'symptom' or else it is an 'indication' that your top-soil, lot, or general situation may not be conducive to the growth of turf-grasses. Please visit my soil fertility web-page for more information about this:

http://hometown.aol.com/eilatlog/fert/fertilex.html
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Here is some more information which may be of help to you:

NATURAL CAUSES of MOSS:

Top-soil vegetative growths called "MOSS"  become established in lawns when grass vigor is reduced, under conditions of poor drainage (high clay), compaction, shade, excessively acidic soil conditions and close mowing.


The most common cause of moss in lawns is a shady, damp soil.

Making for a dryer top-soil is often the easiest fix for a moss problem.
Adding some sand is the least expensive way to help a high-clay soil and improve drainage, but this should be balanced by also adding organic matter like compost.  The organic matter will improve the soil's fertility and help to make it drain better.


Working to improve the aeration and drainage abilities of the top-soil by adding these amendments can prevent mosses and other problems.

If you have lots of clay in your soil, you can work year by year to improve the high clay condition by adding better soil and compost. Eventually things should get better for grasses and worse for mosses.


Periodic commercial aeration of the top-soil and mowing the grass a little higher than usual will help a moss problem at least temporarily.  Some rental stores will have the aerator machines you can rent by the hour.

It also helps to keep thatch build-up at a minimum.
Regular use of compost with thatch removal as a top-soil ammendment can improve the conditions for turf grasses and contribute to a long-term moss cure provided the rest of the requirements for turf-grasses also exist (adequate light and water mainly).

These last moss fixes are not absolute and guaranteed to work, but you may want to try them.
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CHEMICAL and SOIL-CHEMISTRY CAUSES of MOSS:

Some people are in the habit of adding un-necessary minerals to the soil or they will use commercial fertilizers which add them.  If you use commercial fertilizer formulas, always read the label to know what is being added to your soil.

Adding certain minerals (like IRON or SULFUR) may contribute to an acid soil condition (and thus promote moss and other problems).  Most soils are not mineral deficient so a lab-test is recommended before adding these to your top soil unnecessarily. Most lawn and garden centers will sell an easy to use SOIL-TEST KIT so you can find out what your soil's pH is.  This will guide you in regards to adding certain chemicals to the soil.

Adding the un-needed moss-causing minerals to your top-soil can make life difficult not only for the grasses, but for all the microbes in the soil as well.  These microbes are important for the soil ecology that makes for a healthy lawn.

 Nitrogen is THE chemical that does need to be replenished OR re-cycled back to the soil (by composting, e.g.), this element-nutrient is rapidly used not only by the grasses and plants but also by all the helpful microbes in the top-soil.  If the use of nitrate containing fertilizers does not promote a deep greeness and lush growth of your turf grass with sufficient watering,...then chances are you do not have the type of soil for lawn grasses; and such a soil may be conducive to continual moss populations.

If iron and sulfur containing chemicals are contributing to your mossy soil conditions, you can cut-down on adding anything to the soil for a while and/or start using more simple fertilizers like ammonium nitrate which only adds needed nitrogen and no moss-causing or acid-soil causing additives. Using the ammo-nitrate should keep any lawn green while not contributing to soil acidity which can be conducive to moss.


PREVENTION and SPECIALIZED COMMERCIAL DE-MOSSER PRODUCTS:

An herbicide called "SAFER'S MOSS KILLER" which is a soap-base, environmentally safe, product will rid lawns of this type of moss. Safer's Moss Killer is available at:

http://www.victorpest.com/canada/lawn.asp

Garden centers often sell other HERBICIDAL FATTY ACID- SOAP PREPARATIONS as "Organic Herbicides".  These products may be effective for moss. Read the product labels to know what to expect and how to use them.

CHEMICAL TREATMENTS can be carried out at any time of year and for best results when the weather is mild and the soil is moist,... particularly during September and February or March.

Look for chemical "MOSS KILLERS"  based on DICHLOROPHENE and also CRESYLIC ACID. These chemicals are contact in action with little or no residual effect; ...the  moss will usually return if cultural measures  (mentioned above) are not implemented.

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IN SUMMARY;...

Remedies for the moss causing soil conditions usually involve CULTIVATION and HORTICULTURAL PRACTICES of improving soil tilth, drying-aerating the soil (drainage improvement), solarizing and general top soil soil improvement.  A simple process of adding some SAND to a high clay soil or pruning back the shade sources my help a moss prone soil.  All these strategies can usually eliminate the moss and promote turf grasses.


Again,...
all grasses like lots of sun-light and good drainage.  With the best conditions for grasses established,...mosses will become history.
If your lot is in persistant shade,...then you need to grow something other than grasses. However, before you make any major landscape changes,...you may want to try a grass-type like 'Rembrandt' or 'Planatation' TALL FESCUE, ...this grass type is about as shade tolerant a grass there is and may be worth a try. These fescue cultivars are widely available.

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With a good fertile-loamy well draining top-soil, best quality hybrid grass type(s), 1-3 inches of water per week, plenty of sun-light, ...almost anyone can have an excellent lawn with a minimum maintenance effort.
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I Hope this has answered your question(s)!

Visit my Lawn & Gardens webpage for more Tips, Facts and Links:
http://hometown.aol.com/eilatlog/lawnol.html

Your Questions and Comments are welcome at ALLEXPERTS.com
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