Question
What type of manure is the best for my lawn and plants, shrubs and trees, cow or horse?  

Answer
Good morning Andrea:

Some information on manure can be found at:
http://www.ext.colostate.edu/ptlk/1618.html

Cow manure contains 5.7 to 7.2 % Nitrogen of dry weight.
Horse manure contains 3.2 % Nitrogen of dry weight.


Surface applications of manure do not provide the soil aeration, moisture regulation and deep root penetration that is possible when it is mixed into the soil.

At least 2 percent organic matter should be present for growing lawn grasses. Other garden plants will thrive in a soil with about 5 percent organic matter. To add this organic matter spread 1 to 3 inches of peat, compost or well-rotted manure over the soil when other nutrients are added. All these should then be worked to a depth of about 6 inches into the existing soil.

In addition to incorporation in the soil, a mulch of organic matter is beneficial for many flowers, vegetables, trees and shrubs.

Top-dressing of lawns may be done with good topsoil or topsoil-organic material combinations to smooth out irregular areas in the lawn or help decay thatch. Top-dressing does not generally improve the texture or performance of tight, poorly drained soils unless it is done in combination with core aerification.

Results when using manure varies in nutrient value, degree of decomposition, and freedom from weed seeds and disease organisms.

Although nutrients are lost in aging, thoroughly rotted, old manure is much better for plants than the fresh, strawy material. The greatest disadvantage of manure is the weed seeds that are often present.

Composted or dried manure is more desirable since weed seeds and potential human pathogens have been killed.

Fresh manure should not be used except as a light top-dressing on beds. If used in this way it should not touch any plant stems or leaves.

Rather than use manure on the lawn I would stick to the commercial type that I can control the nitrogen application. If you choose to use the manure I would suggest it be dried and used on the vegetable and flower garden only.

Have a good lawn!
Floyd McMahon