western-queensland-gardening-guide.pdf - South West NRM

Particulars for mulch application
Saline areas: Mulch can be used to good effect, as it reduces evaporation from the
. soil surface, thus reducing the rise of salts to the surface in capillary water.
Steep slopes: Mulch can provide protection for soil on steep slopes prone to
erosion.
Cracking clays: Any mulch will help reduce seedling loss on cracking clays by
reducing the severity of the cracks. If sand is used it will fall into cracks that do
occur and reduce drying out and exposure of the roots at depth.
Types of mulches
Bulk mulches: Heavy material such as wood chips, compost plus crushed rock.
Straw and hay: Light and easy to spread.
Woodchips, pine bark: Good, durable mulch but may draw nitrogen from the
soil.
Sawdust, woodshavings: As for woodchips and pinebark above, except may
repel water when settled. This is no problem if the soil surface is dished around
the seeding (See Figure 14).
shallow dish so that
water repelled from
surface of mulch runs
back towards tree
Figure 14. A shallow dish to capture water around base of tree
Leaf litter: Variable performance and durability depending on type. Tends to
decompose readily which is good for the soil, but means it needs reapplying if the
other benefits of mulch are to be maintained.
Compost: Decomposes readily and adds organic matter to the soil. Could be a
major source of weed seed. Needs to be replaced regularly, so generally not
feasible for large plantings.
Shredded paper: A light mulch which should last for a season. May repel water
when compacted - dish soil surface as per Figure 14.