Backpack sprayers are practical for use in small-sized plantings and for spot treatment of weed infestations. When applying Roundup Original with a backpack sprayer, add 10 mL of Roundup Original to 1 L of water. For Gramoxone, use a ratio of 6 mL of product to 1 L of water. Follow the other instructions listed in Table 1. Granular herbicides are more suitable than liquid sprays when debris or dead vegetation is present under shelterbelts.
Granules can fall through to the soil surface, without being intercepted by dead vegetation.
Hand-operated applicators such as Whirlybird, Casoron Spreader and Cyclone are available for spreading granulars. Tractor-mounted spreaders are also available, but they are usually not practical for use in the average shelterbelt. Uniform application and correct calibration are important considerations when using granular formulations. Herbicide product information Table 2 provides information on the registration status of herbicides for use on shelterbelt tree or shrub species, and Table 3 lists the weeds controlled by these herbicides. Other practices, such as choosing a tree species suited to the local conditions and proper planting of seedlings, help tree seedlings to compete with weeds.