The Influence of Treatment Timing and Shrub Size on Chinese Privet (Ligustrum sinense) Control with Cut Stump Herbicide Treatments in the Southeastern United States

Abstract

Since its introduction to the United States in 1852, Chinese privet (Ligustrum sinenseLour.) has spread throughout the Southeast, invading many natural areas. Manual control by cutting or shredding is one of the most common strategies many land managers employ. However, rapid sprouting from the root collar and lateral roots commonly results in poor control. Cutting followed by either glyphosate or triclopyr application to the stumps is generally effective, but the efficacy of these herbicides in relation to treatment timing andL. sinenseroot collar diameter has not been evaluated. The objective of this experiment was to determine the effectiveness of glyphosate and triclopyr cut stump treatments compared with cutting alone at spring and fall timings across a range ofL. sinensesize classes. Studies were conducted at two locations in Auburn, AL. Treatments included cut stump+no herbicide, cut stump+ glyphosate (120 g L−1), or cut stump+triclopyr (90 g L−1). Treatments were applied to at least 50 experimental units each at April and November timings. Root collar diameter was recorded for each stem, stems were cut 2.5 cm above the ground, and herbicide treatments were applied within 30 s.Ligustrum sinensemortality and sprouting were quantified 6, 12, and 18 mo after treatment. Both glyphosate and triclopyr amine were very effective in controllingL. sinenseat both spring and fall timings. However, glyphosate provided slightly better results than triclopyr when lateral sprouting was included. Application timing also was significant, with a lower percentage of sprouting following November treatments than April treatments. Stem size influenced treatment success, as larger stumps tended to sprout more than smaller stumps. These results indicateL. sinensecan be controlled with cut stump herbicide treatment using either glyphosate or triclopyr with spring or fall timings at concentrations much lower than typically used.

Herbicide Options to Control Naturalised Infestations of Cereus uruguayanus in Rangeland Environments of Australia

“…Even lower mortality was reported for woody weeds such as Ligustrum sinense Lour. (14% mortality) [ 27 ] and Ailanthus altissima (Mill.) Swingle (21% mortality) [ 28 ] if herbicide was not applied to the cut stump.…”

Long-Term Suppression of Hardwood Regeneration by Chinese Privet (Ligustrum sinense)

“…Triclopyr applied in high concentrations at the base of the plant in January, when seasonal defoliation is greatest, produced the highest mortality on Chinese privet in hardwood stands in Alabama (Enloe et al, 2016). A similar study found that lower concentrations of triclopyr or glyphosate are effective when applied as a cut stump treatment (Enloe et al, 2018). Triclopyr applied with similar methods on bottomland hardwood sites is an adequate herbicide for Chinese tallow as well, though other herbicides such as aminocyclopyrachlor may perform better (Enloe et al, 2015).…”

Control ofAilanthus altissimausing cut stump and basal bark herbicide applications in an eighteenth‐century fortress

“…The higher efficacy observed in the first run than in the second one, for the A + F treatment, can be attributed to the different periods in which the herbicide treatments were carried out: the first run in summer and the second run in spring. This behaviour is confirmed by the fact that woody species are generally better controlled when plants translocate the reserves to the roots, for winter storage, and not to the shoots as occurs in spring (DiTomaso and Kyser, 2007; Badalamenti et al ., 2015; Enloe et al ., 2018). Moreover, the carbohydrates in the roots are at their lowest level in mid‐summer and the plants, once cut, cannot rely on these reserves to produce new shoot as they generally do, thus their regenerative capacity is at its lowest in this period (Kays and Canham, 1991).…”