Chapter 7b. Turfgrass pest management- weed control by 5vx06o8

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									 Turfgrass Management
           Alanna L. Neely




Chapter 7B Turfgrass Pest Management –
              Weed Control
 Sustaining a turf of acceptable quality
  usually means controlling weed species
  whose presence significantly reduces turf
  quality.
 Besides conducting a cultural program
  that favors vigorous, healthy turfgrass
  growth, it is sometimes necessary to
  institute measures for directly controlling
  potential or actual weed invaders. This
  frequently involves the selection and
  application of appropriate herbicides.
 Weeds: types and species that occur in
  turf.




 Herbicides: types and uses for weed
  control.
                 Weeds
 Definition:
  _____________________________________
  _____________________________________
  ________________- those species that may
  be a weed under a specific set of
  circumstances, and a desirable (turfgrass)
  species under another (i.e., tall fescue,
  creeping bentgrass, Bermuda grass).
 ______ _____- those species that are always
  classed as weeds, regardless of
  circumstances.
 Old sayings:
  ________________________________.
 Botanical weed types- _____, _____, _____.
 Annuals _________________________.
 Winter annuals germinate in the late-summer/
  early fall and die the following summer;
  examples: annual bluegrass, common
  chickweed, and henbit.
 Summer annuals germinate in spring and die
  with the first hard frost in fall; examples:
  knotweed, spurge, and crabgrass.
 Biennials ________________________.
 Perennials _______________________.
   Simple perennials are propagated by
    seed; examples: dandelion and
    plantains.
   Creeping perennials can reproduce by
    ________________________________
    _____________________.
 Functional weed types -
  ________________________________.
 _____ _____- can be controlled with
  ________________________________.
 ______ _____ - generally cannot be controlled
  with postemergence herbicides (phenoxy,
  picolinic and benzoic acids) applied to the
  foliage; however, some annual broadleaf
  weeds may be controlled with some of the
  same preemergence herbicides used for
  crabgrass.
            Weed Species:
               Annual Grasses:




                 Yellow foxtail   Annual bluegrass
Crabgrass




               Fall Panicum       Goosegrass
Sandbur
             Perennial grasses:




                    Bermudagrass             Tall Fescue

Quackgrass




              Nimblewill


Bentgrass

                                                   Yellow
                                                  nutsedge
                               Dallisgrass
                   Broadleaf weeds:




   Dandelion
                   Broadleaf plantain        Buckhorn plantain




Common chickweed   Mouse-ear chickweed         Black medic



                                         Purslane
              Cont.’d




Curled dock               Red sorrel
                Chicory




Ground ivy       Henbit
                          Speedwells
                     cont.’d




Yarrow                         White clover




Yellow wood sorrel             Knotweed
                              Cont.’d




Prostrate spurge                                        Carpetweed
                                Thistles




        Round-leaved mallow

                                           Wild onion/garlic
             Herbicides
 Types:
   A. Preemergence vs. postemergence
     Preemergence herbicides are applied _____ to
      the emergence of target weed species; some are
      effective with early post applications.
     Postemergence herbicides are applied _____
      emergence of the target weed species;
      application prior to emergence are usually
      ineffective.
 Foliar vs. soil applied
   Foliar- applied herbicides are applied _____
    ___________________________________
    __________________________________.
   Soil- applied herbicides are applied _______
    ___________________________________
    ___________________________________
    __________________________________.
 Contact vs. systemic
   _____ _____ are not translocated within the plant; they
    work at the locations of immediate contact with the
    target weeds.
   ______ _____- are translocated within the plant to the
    site (s) of action; excessive rates must be avoided as
    they might result in less effective, contact action.
 Selective vs. nonselective
   ______ _______- selectively kill target species while
    not adversely affecting nontarget (turfgrass) species,
    provided they are applied at the proper rate and under
    the proper conditions.
   _______ ______- are used either for total vegetation
    control of for weed species for which no selective
    herbicides are available.
 Annual grass control:
   Preemergence herbicides include DCPA
    (Dacthal), bensulide (Betasan), Benefin
    (Balan), oxadiazon (Ronstar), and
    pendamethalin (pre-M).
   Postemergence herbicides used to refer to
    several organic arsenicals (MSMS, DSMA)
    which had to be applied several times at 7-
    10 day intervals; now Acclaim (fenoxyprop-
    ethly) and Drive (quinclorac) can be used
    with greater efficacy and safety.
 Perennial grass control:
   Roundup (glyphosate) and Finale (glufosinate)
    are the principal materials used as a spot
    treatment (directed spray of for total vegetation
    control.
   An evolving series of sulfonyl ureas, including
    Corsair (chlorsulfuron) and Certainty
    (sulfosulfuron), can be used for selectively
    controlling selected perennial grasses in some
    turfgrass communities.
   A new herbicide, mesotrione, has been
    successfully for selectivity controlling creeping
    bentgrass and nimblewill in Kentucky
    bluegrass turf.
 Broadleaf weed control:
   Old standard: 2, 4-D +MCPP + dicamba for
    broad-spectrum control with bromoxynil for
    BLW control in seedling turf.
   Added: 2, 4-D + Dichloroprop for tough
    BLWs.
   New add: tryclopyr, or a combination of
    triclopry and clopyralid, in combination with
    2, 4-D for broad-spectrum control.
                Summary
 Weeds, including botanical and functional
  types, and examples of weed species
  occurring in turf.
 Herbicides, including types:
     A. preemergence vs. postemergence
     B. foliar vs. soil applied
     C. contact vs. systemic
     D. selective vs. nonselective
 Controlling weeds with herbicides:
   A. annual grasses
   B. perennial grasses
   C. broadleaf weeds
     Closing Statement

 As in any other facet of turfgrass
  management, turfgrass weed control
  often involves the intelligent use of the
  available tools for accomplishing cultural
  objectives. In this arena the tools are
  called herbicides. When used properly,
  they can provide very satisfactory results;
  used improperly, they can create more
  problems than they solve.

								
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