Page 21 - Griffin Gazette Spring 2017
P. 21

Western Flower Thrips, are fast moving and small, about 1-2 mm in                   marigolds, roses, dracaena, fuchsia, dahlias and ipomoea. Thrips
length, and vary in color from yellow to brown or black depending on                threshold for treatment is usually low because of the potential for
the species. They may be obvious on open flowers or found hidden                    them to spread viruses. Plants such as marigold, dracaena, verbena,
in tight parts of the plants. Adults have tubular bullet-shaped bodies,             impatiens, petunia and fava beans should be used to monitor for
with narrow, pointed and fringed wings held folded over its back.                   their presence. Whiteflies can build quickly and are found often on
The two larval stages that feed on plant parts above ground may                     indicator plants such as tomato, lantana, gerbera daisy, poinsettia
                                                                                    and eggplant.
                                                              be recognized as
                                                              wingless, yellowish,  Potato discs have been used as a
                                                              maggot-like body.
                                                                                    monitoring tool for determining if biological

                                    Spider mites are                                control or insecticide drenches have been

                                    small in size and                               effective in reducing fungus gnat larvae

WFT                        WFT      may appear as                                   populations. Potatoes are cut into 1" x 1"

adult                      larvae   speckles of pepper                              slices and pressed into the soil until flush

                                    against the white                               with the soil surface. If larvae are present,  Potato disc
                                                                                    they will migrate to the underside of the
                                    paper that will

                                    eventually move.                                potato. A time-saving tip is to place flags in plants where you are

                                    The easiest mite to                             using potato discs so they can be easily located, results recorded

                                    identify will be the                            and the potato discs changed out.

                                    two-spotted spider                              The ultimate goal is to effectively manage pest populations. The
                                                                                    next step after recording whole-plant inspections, beat tray counts
Two-spotted spider Spider mite      mite, based on                                  and sticky card counts is to determine what control tactic to use
                                                                                    based on current pest levels populations. Ask yourself these key
                           webbing  the 1-2 large black                             questions: Is the population increasing, decreasing or staying the
                                                                                    same? Am I positive on my diagnosis? What will happen in a week if
mite adult                          spots seen on each                              I do nothing? Are there any environmental or cultural practices that I
                                                                                    can change? Have previous treatments been effective? If not, why?
                                    side of the body.

Adults will have 4 pairs of legs while nymphs will have 3 pairs. These

mites cause a whitish stippling of foliage that may appear similar to a

nutrient deficiency. If they become well established, they can cause

webbing over flowers, stems and foliage. Pay special attention to                   Many considerations weigh into a pesticide decision, including
                                                                                    label requirements, crop safety, rotation by mode of action and
areas of higher movement such as near intake louvers and doors                      life stages treated. The GGSPro team is available to help you with
                                                                                    these decisions. GGSPro has also created a Technical Reference
when scouting.                                                                      Guide and posters to help you make informed choices. Learning
                                                                                    to establish insect thresholds will vary by pest, crop, time of year,
Indicator or trap plants are plants that are highly attractive                      stage of crop, development in production and the intended market.
                                                                                    A threshold can be thought of as a level of pests that triggers the
to certain insects and can be used to detect insect and mite                        need for control measures to be taken. Well-timed, effective and
                                                                                    appropriate applications can reduce the expense of pest control
populations early while populations are still low. Chrysanthemum,                   while providing superior results.

                           fuchsia, sunflower, gazania, portulaca

                           and pepper plants should be inspected

                           carefully for aphids. Cast skins, as well

                           as “honey dew” may be present on

Pepper trap                a plant, providing a clue that aphids

plant for aphids           are present. Spider mites love hot and

                           dry weather and prefer crops such as:

 GGSPro has created
  a database to assist

          growers when
      making decisions

        about pesticide
     applications when

       BCAs are in use.
  Multiple sources are
   used to accumulate

        this information
 including: biocontrol
companies, university

            research and
chemical companies.
  It is fully searchable.

         Please contact
      GGSPro for more

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