DATE:     12/9/99   
WRITERS:  Dr. Don Ham, (864) 656-2480
          Bob Polomski, (864) 656-2604  
EDITOR:   Giles Singleton, (864) 656-3876
 
Using Christmas Tree Mulch

     Q: My city is having a "Grinding of the Greens" programs
where wreaths and Christmas trees are ground up and "recycled"
into mulch. I would like to participate by using the mulch around
my azaleas and other plants in my landscapes, but I'm concerned
about harming my plants. Is this mulch okay for my plants? Should
I compost it first before using it?
     A. When applied to the soil surface in a two- to three-inch
 layer, this mulch will not have to be composted.
     Try to apply the mulch at least six to 12 inches beyond the
branch spread of your shrubs and trees, because the root system
can extend two to three times farther than the branches of a
plant. Mulch as large an area as possible.
     Once the mulch is in  place, pull back the mulch two to
three inches away from the main trunk to keep the stem or bark
dry. For annuals and perennials, apply a mulch layer one to two
inches thick.
     The mulch will help conserve moisture, suppress weeds, and
supply nutrients as it decomposes. You can also use the mulch in
animal pens or garden paths, and along fence rows to suppress 
weeds.
     However, if you mixed this fresh or "green" mulch into the
soil, then you'd run the risk of causing a nitrogen deficiency in
your plants. Because wood mulch contains a lot of carbon and
little nitrogen, the microorganisms responsible for breaking down
the mulch will have to draw upon nitrogen that's already present
in the soil, leaving less available for your plants. Nitrogen-deficient
plants look stunted and their oldest leaves turn yellow.
     If you need to put green mulch directly into the soil, it
would be a good idea to add a nitrogen-containing fertilizer. The
general recommendation is to apply one pound of actual nitrogen
per 100 pounds of dry wood or bark fragments. For example, add
ten pounds of a 10-10-10 fertilizer to supply one pound of actual
nitrogen to a 100-pound pile of mulch   Donald L. Ham, Extension
urban forestry specialist and Bob Polomski, Extension consumer
horticulturist.
     For more information on urban tree care, check out:
http://depts.clemson.edu/extfor/programs/urban_tree_care/ or 
http://depts.clemson.edu/for/arboriculture.htm .
                    *************************
     If you have questions or comments on gardening-related
issues, write to PSA Media Relations, Box 340129, A-101 Poole
Agricultural Center, Clemson University, Clemson, S. C. 29634-0129.
     You might also want to look for other "Buds and Blooms"
columns under 1999 News Releases at: www.clemson.edu/psamedia.
                               END