Strawberry and Raspberry Pest Management in Wisconsin

Strawberry Disease Management
Read product labels carefully before using a fungicide, even if you have
used the fungicide before and are familiar with it. Reentry periods,
preharvest intervals (PHIs) and other safety information can change. Be
aware of contradictory information on labels. For example, captan and
sulfur each has a 0-day preharvest interval but a 24-hour reentry
period. Be conservative; observe the reentry period over the PHI.
Fungicides are only one component of strawberry disease
management; they are not a substitute for good cultural practices (see
below). Thus, it is important to become knowledgeable of the biology
of the crop and its pathogens so that you can develop a disease
management program that is less reliant on pesticides.
FUNGICIDE UPDATE Myclobutanil fungicide previously was sold for use on fruit crops under
the trade name “Nova” and now is sold under the trade name “Rally.”
The formulation is identical, and use recommendations on strawberry
and raspberry, including rates and timing, are unchanged. Growers may
continue to use existing Nova stocks according to the label.
Azoxystrobin fungicide previously was marketed to strawberry and
raspberry growers under the trade name “Quadris” and now is
marketed as “Abound.” Existing stocks of Quadris may be used on
strawberry and raspberry only if you hold the original label listing these crops.
Quadris is still labeled and marketed for use on many vegetable crops,
but newly purchased Quadris may not be used on strawberries or
raspberries.
Abound and Quadris both are highly toxic to certain apple varieties,
especially McIntosh and related varieties. Even a small amount of
Abound or Quadris, such as spray drift or spray tank residue, is toxic to
apple leaves and fruit. Therefore, these products are not recommended
for berry growers who also grow apples.
Orbit (propiconazole) is an older fungicide that only recently has been
labeled for use on strawberry and raspberry. It is in the same class of
fungicides as myclobutanil (Nova, Rally) and is labeled for control of
anthracnose, leaf spot, powdery mildew, and rust. Of these diseases,
anthracnose and leaf spot are common on strawberry in Wisconsin.
Procure (triflumizole), an older fungicide, is now labeled for control of
strawberry powdery mildew and is in the same fungicide class as
myclobutanil (Nova, Rally) and Orbit (propiconazole).
Scala (pyrimethanil) is registered on strawberry for control of gray mold.
Pyrimethanil, the sole active ingredient in Scala, is a component of
Switch, another fungicide effective for gray mold control.
Various phosphorous acid products (also called phosphites or
phosphonates) are registered on several fruit crops. These are related to
fosetyl-aluminum (Aliette), which has been used for many years to
control Phytophthora pathogens of small fruits. On strawberry, these
products are used either as a pre-plant dip to control red stele or they
are applied to leaves, flowers, and fruit to control leather rot. These
products are taken up through leaves and require thorough wetting of
foliage.
Several highly effective fungicides can manage the most important
diseases in Wisconsin. Many newer products are considered “reduced-
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