Agriculture Reference
In-Depth Information
For larger commercial orchards, plastic films and landscape fabrics are
most useful in young, nonbearing fields. Harvesting operations and equip-
ment can damage the films and fabrics in mature orchards.
Organic Mulches
Mulching crop rows with organic materials after planting can help manage
weeds and is very popular for organic orchards. As with dark plastic films
and fabrics, organic mulches reduce the amount of light that reaches the
soil surface, thereby reducing weed populations. Seeds of many weed species
must be exposed to light in order to germinate.
Types.
The types of mulches vary by region, historically representing waste
products from agriculture or forestry. In the northwestern United States,
southeastern United States, and western Canada, bark and sawdust from
lumber yards are often available locally. In orchard trials in British Columbia,
researchers found that locally available wood wastes provided season-long
weed control when used as mulches. In other trials across North America,
wood chip and bark mulches usually provided good weed suppression for
about 3 years before they needed replacing. Once free for the taking,
however, these materials now have value as fuel for industry and municipal-
ities and can be expensive to purchase, transport, and apply on a large scale.
In grain-growing regions, straw is often readily available and can be used
for mulching. Straw mulches, however, provide excellent habitat for rodents
and are generally not good choices for organic orchards. Many communit-
ies across North America now recycle yard wastes, either chipping them for
use as mulches or composting the wastes. Be sure the straw or recycled yard
wastes are free of pesticides before applying them to your orchard.
Coarse-textured products, such as bark and wood chips, generally help
control weeds with fewer problems than fine-textured materials such as saw-
dust. In windy areas, it can be difficult to keep sawdust and fine bark from
