Terms to Become Familiar With. Residual Remains active in the soil (anywhere from several weeks to 12 months or more) and is absorbed into the plant via the root system. Herbicides that have long residual times in the soil are generally not used for bushland weed control. Toxicity The strength of a herbicide, and hence the level of risk involved in its use. Systemic The herbicide is transported around the plant to the roots, which it kills, causing the whole plant to die. Non-systemic The herbicide only kills the part of the plant that it contacts. Also known as ‘Knockdown’ herbicides. Useful for the control of annual weeds. Selective The herbicide kills some groups of plants but has little or no effect on others. Common examples are ‘broad-leaf selective’ herbicides and ‘grass selective’ herbicides. Non-selective The herbicide can kill all groups of plants. Active Ingredient The ingredient in the herbicide that actually kills the plant. Don’t confuse this with the brand name of a herbicide. The label on every brand of herbicide will show what active ingredient(s) are present and in what concentrations.
Terms to Become Familiar With. Residual Remains active in the soil (anywhere from several weeks to 12 months or more) and is absorbed into the plant via the root system. Herbicides that have long residual times in the soil are generally not used for bushland weed control. Toxicity The strength of a herbicide, and hence the level of risk involved in its use. Systemic The herbicide is transported around the plant to the roots, which it kills, causing the whole plant to die. Non-systemic The herbicide only kills the part of the plant that it contacts. Also known as ‘Knockdown’ herbicides. Useful for the control of annual weeds. Selective The herbicide kills some groups of plants but has little or no effect on others. Common examples are ‘broad-leaf selective’ herbicides and ‘grass selective’ herbicides. Non-selective The herbicide can kill all groups of plants. Active Ingredient The ingredient in the herbicide that actually kills the plant. Don’t confuse this with the brand name of a herbicide. The label on every brand of herbicide will show what active ingredient(s) are present and in what concentrations. Surfactant A herbicide additive like a strong detergent which assists the herbicide to stick onto the plant thereby increasing the uptake of the active ingredient by the plant. Some brands of herbicide already have a surfactant mixed in or will recommend that one be included with the herbicide for use on a particular species. This information will be shown on the label. Penetrant A herbicide additive which assists the active ingredient to move into the plant. Some brands of herbicide already have a penetrant mixed in or will recommend that one be included with the herbicide for use on a particular species. This information will be shown on the label. In most cases the use of additional penetrants is not recommended for bushland weed control and should only be used with great care.
