Commonly known as Bosc’s mille graines, Oldenlandia boscii (de Candolle) Chapman is a perennial broadleaf weed belonging to the Rubiaceae family. It is native to the southeastern United States and is commonly found in sandy or loamy soils, particularly in moist or seasonally wet turfgrass areas, roadsides, and disturbed areas (LeGrand et al. 2025; USDA-NRCS 2025; Weakley 2025).

Bosc’s mille graines (BMG) has prostrate to spreading growth habit (Figure 1A). BMG leaves are oppositely arranged and are linear to narrowly elliptic, typically 0.04 to 0.12 inches wide and 5 to 10 times longer than their width (Figure 1B) (Allain and Reid 2025; Weakley 2025). BMG stems are highly branched and smooth. The inflorescences comprise a tight cluster of flowers at the juncture of the stem and leaf (Figure 1C). BMG plants have a perennial life cycle and a deep, woody taproot (Figure 1D). Flowers have sepals visible from the top view and produce four tiny, white petals. After flowering, BMG produces capsules measuring 0.06 to 0.12 inches long that contain black or brown seeds (Figure 1E) ranging from 0.004 to 0.01 inches in length; each capsule contains at least 120 seeds (Terrel and Robinson 2006). BMG flowers from mid-July to September and enters dormancy during winter months in North Carolina (LeGrand et al. 2025).

Figure 1. Bosc’s mille graines plant characteristics include multiple tillers (A), opposite leaf arrangement with glabrous stem (B), inflorescence in leaf axils (C), deep taproot (D), and capsule producing multiple seeds (E).

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Figure 1. Bosc’s mille graines plant characteristics include multiple tillers (A), opposite leaf arrangement with glabrous stem (B), inflorescence in leaf axils (C), deep taproot (D), and capsule producing multiple seeds (E).

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Weed infestation can disrupt turfgrass aesthetics and reduce overall quality. BMG interferes with turfgrass uniformity by spreading aggressively via seeds across managed areas. Due to its high regrowth capacity and mat-forming ability, BMG can persist after mechanical disturbance or after a herbicide application, which complicates managing fields after sod harvests. BMG is highly competitive. It establishes at densities of 17 to 19 plants per square foot (Figure 2), and each plant produces 15 to 19 shoots. In the past two years, several sod producers across North Carolina have reported increasing infestations of this species following sod harvest (Figure 2). Other problematic species from the Rubiaceae family include Florida pusley (Richardia scabra L.), old world diamond-flower (Oldenlandia corymbosa L.), poorjoe (Diodia teres Walt.), and Virginia buttonweed (Diodia virginiana L.). Poorjoe can be easily confused with BMG. However, unlike BMG, poorjoe has hairs on the stem and fruit, and poorjoe flower sepals are not visible from above, as they are small and borne at the base of the corolla tube. BMG flower sepals are visible from above and borne close to petals (Figure 1). The Rubiaceae family weeds discussed previously are difficult to control in turfgrass because of limited efficacious, preemergence (PRE) herbicide options, and postemergence (POST) control also requires repeat applications of acetolactate synthase (ALS) inhibitors and synthetic auxin herbicide-based admixtures (Derr 2012; Hutto et al. 2008; Kelly and Coats 2000).

Despite its presence in several counties in North Carolina (LeGrand et al. 2025), there is no published information on how to manage this problematic species in warm-season turfgrasses. Sod producers reported that traditional programs utilizing a single application of synthetic auxin herbicides failed to provide commercially acceptable control of BMG in warm-season grasses and led to weed seed-bank buildup following escapes (Ray McCauley, personal communication).

Figure 2. Bosc’s mille graines (BMG) in zoysiagrass sod field (left); a recently harvested zoysiagrass area densely infested with BMG (center); and St. Augustinegrass fields infested with BMG following sod harvest in southeastern North Carolina (right).

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Figure 2. Bosc’s mille graines (BMG) in zoysiagrass sod field (left); a recently harvested zoysiagrass area densely infested with BMG (center); and St. Augustinegrass fields infested with BMG following sod harvest in southeastern North Carolina (right).

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During the 2025 growing season, research trials were conducted in Council, North Carolina, to evaluate the performance of several POST herbicide programs in controlling BMG in sod production of warm-season turfgrass species. Good control of BMG (80%) was documented at four weeks after treatment with application of Triclopyr at 24 fluid ounces per acre alone or tank-mixed with Quicksilver at 2.1 fluid ounces per acre; Triclopyr at 32 fluid ounces per acre; Trimec Classic at 64 fluid ounces per acre; and Sublime at 32 fluid ounces per acre. BMG warrants sequential herbicide application for achieving excellent control (90%), as a single application is not sufficient. Transient suppression of BMG was observed after single applications of Avenue South, Fahrenheit, and Speedzone Southern, but the weed quickly recovered.

Sequential applications of Avenue South provided good control of BMG (>80%), but SpeedZone Southern and Fahrenheit poorly controlled BMG (<70%) at 12 weeks after treatment (Table 1). Triclopyr (both rates), Triclopyr + QuickSilver, Trimec Classic with or without QuickSilver, and Sublime controlled BMG at 90% or greater, demonstrating excellent control after sequential applications (Table 1).

In zoysiagrass sod fields, sequential applications of Sublime and Triclopyr can cause unacceptable injury (>20%), but turfgrass will recover from transient injury by 10 weeks after treatment. Injury symptoms due to Sublime treatment consisted primarily of bleaching, whereas stunting and chlorosis appeared after Triclopyr applications. Sequential applications of Trimec Classic (64 fluid ounces per acre) or tank-mixing Trimec Classic (32 fluid ounces per acre) with QuickSilver (2.1 fluid ounces per acre) will be effective herbicide options for managing BMG in zoysiagrass sod production with minimal injury concerns.

In St. Augustinegrass sod fields, treatments containing Sublime (32 fluid ounces per acre), Triclopyr (both rates); Triclopyr (24 fluid ounces per acre) with Quicksilver (2.1 fluid ounce per acre); and Trimec Classic (64 fluid ounces per acre) caused severe injury (>30%) but provided excellent control of BMG. However, sequential application of Trimec Classic (32 fluid ounces per acre) tank-mixed with Quicksilver (2.1 fluid ounces per acre) caused minimal injury, and turfgrass recovered by 10 weeks after treatment. Sequential application of this admixture of Trimec Classic with Quicksilver can be utilized for maintaining season-long POST control of BMG in St. Augustinegrass, if transient injury can be tolerated.

It is important to note that the Trimec Classic label permits up to 29 fluid ounces per acre per single application on St. Augustinegrass but warns of increased injury risk from broadcast applications when air temperatures exceed 90°F (PBI-Gordon Corporation 2026). Information regarding PRE herbicide efficacy against BMG is not available, so future research will evaluate other PRE and POST programs for BMG management with the intent to further reduce turfgrass phytotoxicity concerns.

*Add nonionic surfactant at a rate of 1 quart per 100 gallons of spray mix. ↲

**Consult herbicide label for the rates for different turfgrasses. Key: Excellent = 90% to 100% control; Good = 80% to 90% control; Fair = 70% to 80% control; Poor = suppression or less than 70% control. Treatments need to be applied sequentially at 4-week intervals. ↲

The first step in weed management is to identify the pest correctly. BMG can be confused with other Rubiaceae family weeds, especially poorjoe. Using the characteristics described in Figure 1 can be helpful in identifying BMG. If you are still having issues identifying BMG, contact NC State Extension staff for assistance.

Scouting sod fields or lawns in late spring to early summer is an essential step for intervention of weed infestation at early stages. When encountered for the first time, eliminate BMG from managed areas and prevent it from producing seed. Hand-weeding or spot treatment with nonselective herbicides like glyphosate are feasible options for tackling early stages of invasion. If BMG is already present on a large scale, consider making broadcast herbicide applications that provide effective control with minimal turfgrass injury.

Proactive management of BMG is crucial due to its aggressive growth habit, deep taproot, regrowth potential, and high fecundity, which can lead to quick buildup of a seed bank if left unmanaged. Turfgrass practitioners should avoid relying on a single POST herbicide application because BMG can regrow following transient suppression. Sequential POST applications will be effective for season-long weed control, combined with rotation of herbicide modes of action, when feasible, to mitigate herbicide resistance risk. Herbicide efficacy may vary with weed growth stage, as systemic herbicide applications in late summer to fall are more effective in controlling established perennial weeds with extensive rootstock. In addition, turfgrass managers should consider turfgrass phytotoxicity before treating large acreage and follow the instructions on herbicide labels to minimize injury.

Allain, L., and C. Reid. 2025. Oldenlandia boscii. Plants of Louisiana website. ↲

Derr, J. F. 2012. "Broadleaf Weed Control with Sulfonylurea Herbicides in Cool-Season Turfgrass." Weed Technology 26 (3): 582–6. ↲

Hutto, K. C., B. J. Brecke, and J. B. Unruh. 2008. "Comparison of Flazasulfuron to Pyridine Herbicides for Virginia Buttonweed (Diodia virginiana) Control." Weed Technology 22 (2): 351–3. ↲

Kelly, S. T., and G. E. Coats. 2000. "Postemergence Herbicide Options for Virginia Buttonweed (Diodia virginiana) Control." Weed Technology 14 (2): 246–51. ↲

LeGrand H., B. Sorrie, and T. Howard. 2025. Vascular Plants of North Carolina website. ↲

PBI-Gordon Corporation. 2026. Trimec Classic herbicide label. ↲

Terrell, E. E., and H. Robinson. 2006. "Taxonomy of North American Species of Oldenlandia (Rubiaceae)." Sida, Contributions to Botany 22: 305–329. ↲

USDA-NRCS. 2025. Oldenlandia boscii (DC.) Chapm. PLANTS Database. U.S. Department of Agriculture, Natural Resources Conservation Service. ↲

Weakley, A. S. 2025. Flora of the Southeastern United States Web App. University of North Carolina Herbarium, North Carolina Botanical Garden. ↲

The authors thank Grady Miller and Ramon Leon for reviewing the manuscript.