The use of weed barrier has become a fairly common practice in the Great Plains in the establishment of woody seedlings for windbreak and shelter-belt plantings.

The synthetic mulches have several positive advantages for improving tree seedling growth. They increase soil temperatures in the spring, reduce evaporative soil moisture loss during dry periods, and control herbaceous competition, often for an extended period of time.

It is the durability of the synthetic mulches that may cause problems later in tree plantings. It was initially believed direct sun and weathering processes would cause the mulches to break down in five to seven years. However, through studies it is obvious many of the mulches are exceeding life expectancy due to the shading of the material and covering by tree-leaf litter and grassy vegetation.

The higher priced UV-resistant woven fabrics can be more expensive initially and may present problems later. The problem of girdling can occur if the woven fabric will not expand easily as the tree grows and can eventually cause the tree to die. If trees are dying in a shelter-belt situation, landowners should check the base of the tree and see if girdling is occurring. If girdling is observed, the material at the base of the tree must be cut to prevent further injury, or eventual death of the trees will result.

— Terry Conway is a resource conservationist for Natural Resources Conservation Service in Salina.