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Weed suppression has been observed in the fine fescues, a group of low‐input turfgrasses. Of the fine fescues, Chewings fescue (Festuca rubra L. ssp. commutata Gaudin; CH) and strong creeping red fescue (F. rubra L. ssp. rubra Gaudin; ST) displayed the strongest weed suppression ability in previous research while hard fescue (F. brevipila Tracey; HF) did not appear to have the same level of suppression. However, most of this research occurred more than 10 years ago and did not lead to improved cultivars. There is a need for confirmation of these results using diverse germplasm that may have genetic variability for weed suppression; this information would be useful for turfgrass breeding efforts. Our objective was to screen for weed suppression abilities in 19 fine fescue accessions originally collected in Europe, at two distinct field locations, St. Paul, MN and West Lafayette, IN, infested with smooth crabgrass (Digitaria ischaemum (Schreb.) Schreb. ex Muhl.). Our results confirmed previous reports that the F. rubra taxa are more crabgrass suppressive than HF. Chewings fescue and slender creeping red fescue [F. rubra L. ssp. littoralis (G. Mey.) Auquier; SL] displayed the strongest ability to suppress smooth crabgrass. Results also indicated that there is large variability between the entries within each taxon, including within HF. Slender creeping red fescues were relatively more weed suppressive than previously shown, and this taxon needs further attention. Results suggest further opportunities for plant breeders to develop new weed suppressive cultivars for low‐input turfgrass systems. Core Ideas: Festuca rubra taxa are more crabgrass suppressive than F. ovina.There is large variability in weed suppression across entries within each fine fescue taxon.Opportunities exist for plant breeders to develop new weed suppressive cultivars.Future studies should aim to separate allelopathic effects from plant competition. [ABSTRACT FROM AUTHOR]

Preemergence (PRE) herbicides are used to control crabgrass (Digitaria spp.). Single spring applications are common in areas with relatively low crabgrass pressure, whereas sequential applications often are used to extend control in locations with high crabgrass pressure. Our objectives were to determine if changing a.i. in initial and sequential applications affects crabgrass control and if single spring applications of tank-mixed PRE herbicides provide season-long crabgrass control. Studies were conducted 2009, 2010, and 2011 in West Lafayette, IN, and 2011 in Wymore, NE. The PRE herbicides prodiamine, pendimethalin, and dithiopyr were tested using different application strategies. Sequential applications were applied mid-April and mid-June using all possible combinations of the three herbicides and untreated for the initial and sequential application. These herbicides also were applied mid-April as single full-rate PRE application or as a tank mixture of two PRE herbicides at half-plus-half or half-plus-quarter rate. Season-long crabgrass control was consistently achieved using sequential applications regardless which of the three herbicides was used for initial or sequential applications. Single applications of tank mixtures also provided consistent crabgrass control, equivalent to single full-rate applications of the individual PRE herbicides. Tank mixtures of half-plus-quarter rate and single half-rate applications resulted in more crabgrass cover than single full-rate or half-plus-half rate applications regardless of the herbicide applied. [ABSTRACT FROM AUTHOR]