Gravel: mulches

In dry climates, a mulch of rocks and gravel will often trap and condense moisture and direct it to the soil surface. 

Gravel and slate waste are good around plants that like dry, hot conditions. A mulch membrane beneath the gravel will stop them from working down into the soil and hence make these decorative mulches last longer. 

Mulch A, Graham S A, Chamberlain CP (2006) Hydrogen isotopes in Eocene river gravels and paleoelevation of the Sierra Nevada. Science 313(5783) 87-89... 

Put a layer of mulch, such as bark chips or gravel, around the plants to slow down evaporation from the soil and to suppress weeds. 

In studies conducted in Texas, Adams (1965) found that the soil surface and mulch-soil interface temperatures were in the following order on fallow plots bare > 1-inch gravel > 2-inch gravel > 2-inch straw. The daily soil temperatures at 1.30 p.m. from early June to mid-August varied from 90° to 95°F at a depth of 3 inches under bare soil, but were near 80° F under a 3-inch straw mulch. 

In light of injury statistics identilying falls as the primary hazard, impactabsorbing material is paramount to injury mitigation. Safety mulch, wood chips, and even pea gravel has been used to absorb or soften the blow to a child that has fallen. Measures such as this are viewed by safety professionals as injury prevention versus accident prevention strategy. 

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