Advanced Weed Control

Transcription

1 Advanced Weed Control Fred Yelverton, PhD North Carolina State University

2 Weed Control in Newly Seeded Areas Tupersan & Drive

3 Large Crabgrass (Digitaria sanguinalis) McCarty, Murphy & Yelverton

4 PRE Crabgrass Control in Newly Planted Cool-Season Turfgrasses Tupersan 50WP (siduron) PRE control of crabgrass, foxtails, downy brome, barnyardgrass, Weak on goosegrass, fall panicum, Does not control broadleaves, sedges, Control in newly seeded cool-season turfgrass (bents, fescue, ryegrass & bluegrass) areas. Do not use PRE or POST planting warm-season grasses, Apply 20 lbs/a and water-in with ½-inch within 3 days of application for PRE activity. Provides 30 to 45 days suppression.

5 PRE Crabgrass Control in Newly Seeded Cool-Season Turfgrasses Drive 75DF (quinclorac) PRE crabgrass control Newly seeded annual bluegrass, ryegrass, fescue, buffalograss, bermudagrass, & zoysiagrass, PRE or POST sprigging of bermuda or zoysiagrass, Apply 1 lb/a and water-in with ½-inch within 3 days of application for PRE activity. Provides 30 to 45 days suppression.

6 Early POST Crabgrass Control in Newly Seeded Turfgrasses Rule-of-thumb: wait until the 4 th mowing &/or at least 1 month after emergence before treatment, Drive 75DF (quinclorac): 0.5 to 1 lb product/acre (0.56 to 1.12 kg/ha) Apply 7 days after turfgrass emergence, Controls crabgrass, foxtail, many small broadleaf weeds, especially clovers, Provides 30 to 45 days suppression, Water-in with ½-inch (13 mm) within 3 days of application for PRE activity.

7 Early POST Grass Control in Newly Seeded Cool-Season Turfgrasses Early POST (after the 2 nd mowing), Acclaim Extra (0.57 EC), ~16 oz/a, 4 weeks after emergence, MSMA 6L, 0.7 to 1.3 pts/a (0.5 to 1 lb ai/a), or CMA (Calar, Crab Killer II, 1 lb ai/a. after the 3 rd mowing,

8 Poa Control in Newly Planted Cool-Season Turfgrasses PRE control: apply a residual herbicide such as Dimension, Pendimethalin or Barricade in late August after 4 th mowing. POST control: Prograss (ethofumesate) is only selective control in cool-season grasses. Apply during peak Poa germination & repeat in 30 to 45 days. May be applied anytime to tall fescue, 2 weeks after perennial ryegrass emergence & 8 weeks after Ky. bluegrass emergence.

9 Sedge Control in Newly Planted Turfgrasses MSMA 6L at 0.7 pts/acre, after 3 rd mowing, Sedgehammer (halosulfuron) or Basagran (bentazon), turf must be well established before use Multiple applications are necessary.

10 Control of Specific Weeds

11 Southern crabgrass Smooth crabgrass

12 Crabgrass Germination Late winter/early spring when soil temperatures at 4-in. depth reach 53 to 58 F for 24 continuous hours. Germination generally coincides flowering of redbuds, pears. with forsythia, phlox, Has high light requirement for optimum germination, thus, thick turf discourages.

13 Preemergence Herbicide Comparison - Weed Control E=Excellent (>89%) G=Good (80 to 89%) F=Fair (70 to 79%) Herbicide Balan (benefin) Barricade (prodiamine) Betasan/Bensumec (bensulide) Dimension (dithiopyr) Pendulum (pendimethalin) Ronstar (oxadiazon) Surflan (oryzalin) XL/Team Pro Crabgrass Oxadiazon + either prodiamine (Regalstar II 1.2G), benefin (Regalstar 1.5G), dithiopyr (SuperStar) or bensulide (Goosegrass/Crabgrass Control). Repeat applications 60 to 75 days apart are necessary for season-long control. G E G E E G E E

14 Herbicide Preemergence Crabgrass Control % Control Surflan (oryzalin) 80 Pendulum (pendimethalin) 80 Barricade (prodiamine) 90 Team Pro (benefin + trifluralin) 90 Ronstar (oxadiazon) 85 Dimension (dithiopyr) 85 4-year average, 2 apps Rated late summer

15 PRE Herbicides for Bentgrass Putting Greens Trade Names Weedgrass Preventer, Betasan, Bensumec Goosegrass/Crabgrass Control Dimension Tupersan Common Name Bensulide Bensulide + oxadiazon Dithiopyr Siduron

16 Crabgrass POST control - Repeat applications of: In bentgrass, Calar 1 lb ai/a (1.12 kg ai/ha) Repeat in 7 days. In ryegrass, fescue, bluegrass, Acclaim Extra (0.57 EC) (fenoxaprop) at 1½ pts/a (1.8 L/ha)

17 POST Grass Weed Control in Cool-Season Turfgrasses Repeat applications of: CMA (Calar, Crab Killer II, 1 lb ai/a (1.12 kg ai/ha). Taller mowed bentgrass, fescue, bluegrass. Acclaim Extra (0.57 EC) (fenoxaprop) at 1½ pts/a (1.8 L/ha). Taller mowed ryegrass, fescue, bluegrass Drive 75 DF 1lb/a (1.12 kg/ha). Taller mowed bentgrass, ryegrass, fescue, bluegrass

18 POST Grass Weed Control in Cool-Season Turfgrasses (cont.) Repeat applications of: Fusilade T&O 2EC 3 to 6 oz/a (tall fescue only), add Turflon Ester at 2 pts/acre to increase control. Vantage 1L 1½ to 2¼ pts/a (fine fescue only) repeat applications in 1 to 4 weeks good soil moisture present, temps. <80 F fall applications are best followed by spring

19 Postemergence Crabgrass Control 1. POST grass herbicides are most effective on seedling grasses. This size 2. Apply during good growing conditions.. Not this

20 McCarty, Murphy & Yelverton Goosegrass (Eleusine indica)

21 Goosegrass Summer annual, thrives in wet, compacted (low oxygen containing) soils. Germinates when soil temperatures at 4-inches reaches 60 to 65 F for 24 continuous hours. Alternating warm/cool temperatures highly favors germination. Usually 2 to 4 weeks later than crabgrass germination, often when dogwoods and azaleas bloom. Perenniates in subtropical regions.

22 Preemergence Herbicide Comparison - Weed Control E=Excellent (>89%) G=Good (80 to 89%) F=Fair (70 to 79%) Herbicide Balan (benefin) Barricade (prodiamine) Betasan/Bensumec (bensulide) Dimension (dithiopyr) Pendulum (pendimethalin) Ronstar (oxadiazon) Surflan (oryzalin) XL/Team Pro Goosegrass Oxadiazon + either prodiamine (Regalstar II 1.2G), benefin (Regalstar 1.5G), dithiopyr (SuperStar) or bensulide (Goosegrass/Crabgrass Control). Repeat applications 60 to 75 days apart are necessary for season-long control. F G-E F G-E G-E E G G

23 Goosegrass (Eleusine indica) 3-5 leaf 5-6 leaf 2 tiller flowering

24 T. Lowe, USGA

25 Goosegrass Control In taller mowed cool-season grasses, Repeat Acclaim Extra (0.57 EC) at 1½ pts/a or Fusilade T&O (2EC) at 5 to 6 oz/a on 30 day intervals. On fairway bentgrass, Acclaim 4 to 8 oz/a every 3 to 4 weeks. Avoid drought- & heat-stressed turf.

26 Dallisgrass (Paspalum dilatatum) Clumping perennial, Often from prior pastures/forages, Reproduces by seed & short rhizomes, Produces unsightly seedheads in summer, Widely distributed.

27 Thin Paspalum (Paspalum setaceum) McCarty, Murphy, & Yelverton

28 Summer application injury No treatment MSMA

29 Tupersan application (sprayed)

30 Timely applications of high rates of Tupersan will suppress bermudagrass growth.

31 Tupersan Use Tupersan 4.6% G 17 lbs per 1,000 sq ft Gandy drop spreader setting No. 59 Water-into root zone Apply in April, May, September, October Do not apply in June, July and August

32 Granular Tupersan and a drop spreader are convenient to use.

33 Correct rate of Tupersan

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35 Mesotrione (Out Play) New turf active ingredient Naturally occurring phytotoxin Has pre- and postemergent activity Grass and broadleaf weeds

36 Mesotrione Reported to have activity on Large crabgrass (Digitaria sanguinalis) Smooth crabgrass (Digitaria ischaemum) Henbit (Lamium amplexicaule) Broadleaf plantain (Plantego major) Yellow woodsorrel (Oxalis stricta) Nimblewill (Muhlenbergia schreberi) Has applications in cool- and warm-season turfgrass

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38 % Control Smooth Crabgrass Control Late September 35c 84ab 71b 86ab Mesotrione 0.31 Mesotrione 0.62 Barricade d PRE 4-3 POST 7-30 Rates are lb ai per acre. PRE trts were applied 4-3 while POST trts were applied 7-30 and included NIS. When POST trts were applied, crabgrass averaged 2 tillers.

39 % Control Postemergent Smooth Crabgrass Control bc 90a 83ab Mesotrione d Mesotrione Late August Late September Rates are lb ai per acre. Trts were applied 7-30 and included NIS. Crabgrass averaged 2 tillers.

40 % Control Smooth Crabgrass Control with Pre- and Postemergent Applications a 94a 94a 76ab 86ab 89ab Mesotrione.31 fb.31 Mesotrione.31 fb Mesotrione.62 fb Late August Late September Rates are lb ai per acre. PRE trts were applied 4-3 while POST trts were applied 7-30 and included NIS. When POST trts were applied, crabgrass averaged 2 tillers.

41 Mesotrione 0.25 lb ai applied May 1 (1-3 lf crabgrass), photo taken June 14

42 Mesotrione lb ai applied May 1 (1-3 lf crabgrass), photo taken June 14

43 Mesotrione 0.25 lb ai applied June 6 (5-7 lf crabgrass), photo taken June 14

44 Mesotrione lb ai applied June 6 (5-7 lf crabgrass), photo taken June 14

45 % Control Crenshaw Bentgrass Control in Tall Fescue Outplay X 2 Outplay X 2 Outplay X Outplay fb fb Outplay X 4 Fusilade X 2 Fus + Out X 2 LSD= Data collected 28 DAIT. Rates are lb ai per acre. Outplay 4SC contained NIS and were made Oct 11, Oct 26, Nov 08, and Nov 17 as noted. Fusilade containing treatments contained Crop Oil were applied Oct 26 and Nov 08.

46 % Control Crenshaw Bentgrass Control in Tall Fescue Outplay X 2 Outplay X 2 80 Outplay X Outplay fb fb Outplay X 4 Fusilade X 2 Fus + Out X 2 LSD=2.6 0 Data collected 48 DAIT. Rates are lb ai per acre. Outplay 4SC contained NIS and were made Oct 11, Oct 26, Nov 08, and Nov 17 as noted. Fusilade containing treatments contained Crop Oil were applied Oct 26 and Nov 08.

47 % Control Crenshaw Bentgrass Control in Tall Fescue Outplay X 2 Outplay X 2 Outplay X Outplay fb fb Outplay X Fusilade X 2 Fus + Out X 2 LSD= Data collected April , 190 DAIT. Rates are lb ai per acre. Outplay 4SC contained NIS and were made Oct 11, Oct 26, Nov 08, and Nov 17 as noted. Fusilade containing treatments contained Crop Oil were applied Oct 26 and Nov 08.

48 Nontreated photo taken

49 Outplay fb photo taken

50 Outplay fb fb photo taken

51 Outplay fb fb photo taken

52 Outplay fb fb fb photo taken

53 Fusilade X 2 photo taken

54 Fusilade + Outplay X 2 photo taken

55 In dormant bermudagrass, spot treat with Roundup Pro 4L at 2 oz/gal water, avoid desirable green plants, Tall Fescue Perennial Seed contaminant or escape In Ky. bluegrass, fine fescue, zoysiagrass, or bermudagrass, TFC or Corsair 75 DF at 4 to 5 oz/a or as a spot treatment at 2½ grams/2 gal water. In Ky. Bluegrass, Certainty 75WP at 0.75 oz/a, twice 3 weeks apart. In bermudagrass, Revolver 0.19SC at 15 to 26 oz/a, Monument 75WDG at 0.33 oz/a, or Certainty at 1 oz/a.

56 POST Ryegrass Control in Bentgrass Corsair 75WP: Bentgrass fairways mowed at >0.5 inch, not labeled for greens 1 to 2 oz product/acre, May also be used on established Ky. Bluegrass, fine fescue, bahiagrass and bermudagrass. Do not apply to saturated soil or during heat or drought stress, Add a non-ionic surfactant at 0.25% v/v. Also controls tall fescue, chickweed, henbit, pigweed, wild mustard, purslane and other weeds. A repeat application may be needed after 60 days.

57 Preemergence Herbicide Comparison - Weed Control Herbicide E=Excellent (>89%) G=Good (80 to 89%) F=Fair (70 to 79%) Atrazine/Simazine Balan Barricade Betasan/Bensumec Dimension Kerb Pendimethalin Ronstar Surflan Poa annua XL/Team Pro G Oxadiazon + prodiamine (Regalstar II 1.2G), benefin (Regalstar 1.5G), dithiopyr (SuperStar) or bensulide (Goosegrass/Crabgrass Control). Repeat applications 60 to 75 days apart are necessary for season-long control. E G G F-G G E G-E G G-E

58 Uniformity of Application. Uniformity of product size. PRE Herbicide Performance: Fineness of material, generally best to use at least 250 lbs product per acre for uniformity. Application Frequency. Rainfall or Irrigation Amounts & Timing After Application. Topography (Drainage Problems). Soil Persistence Characteristics. Soil Type - Sand, Clay, OM. Thatch. Leaching, solubility, volatility, photodecomposition.

59 Preemergence Herbicide Comparison Herbicide Costs Effects on Rooting* Residual Green Use Barricade low poor good NR Betasan/Bensumec low poor good R** Dimension medium poor good R** Pendimethalin low poor good R** Ronstar 2G high minor good R** Surflan low poor good NR *Refers to nonestablished turf only. **R=Some formulations are registered. NR=Non registered for green use. Consult label for overseeding grass tolerance.

60 PRE Herbicides for Bentgrass Putting Greens Trade Names Weedgrass Preventer, Betasan, Bensumec Goosegrass/Crabgrass Control Dimension Tupersan Common Name Bensulide Bensulide + oxadiazon Dithiopyr Siduron

61 PRE Herbicides for Bentgrass Fairways Betasan, Bensulide, Pre-San, Lescosan, etc. (bensulide) Dimension (dithiopyr) Crabgrass/Goosegrass Preventer (oxadiazon + bensulide) Gallery (isoxaben) Barricade (prodiamine) Pre-M, Pendulum, etc. (pendimethalin) Tupersan (siduron)