I am seeking to replace manufactured mulches with choices that lower carbon emissions during their life-cycle (manufacture, transportation, use, and disposal). The most readily available and affordable mulch for my garden is a cypress mulch blend. This product requires the conversion of live trees to a decomposable product (carbon storage becomes carbon emissions); transport of a bulky material over thousands of miles (transportation emissions), and transport from retail outlet to home (transportation emissions). While the benefits of manufactured mulches in home gardening are manifold, their carbon footprint is problematic.
Are living mulches of long-lived perennials an alternative? Are there perennial ground covers compatible with mixed perennial plantings that could provide at least a portion of the benefits of manufactured mulches? Does Extension advise on the use of such mulches from the perspective of reducing carbon emissions? Is there any research into the use of long-lived, perennial mulches as a means to reduce the carbon emissions from transportation and decomposition of manufactured mulches? (I am not speaking of annual cover crops; that's another matter.)
Several parts to this question. Chipped woord from your city or county is often available for free to keep it out of the landfill and is the best mulch available as it is in large chunks that cover well but does not provide nutrients and "hold" to germinate weed seeds. As it degrades it provides nutrients and organic matter to the bed. Ground covers help keep the ground cool, but need moisture to live and allow transevaporation.