Fortress is a combination herbicide containing two selective active ingredients that provide a broad spectrum of weed control with excellent plant tolerance on ornamentals. Fortress is for preemergence control of weeds in field and container ornamentals. Fortress is a granular herbicide containing two selective herbicides that provide a broad spectrum of weed control with tolerance to many ornamental plants.

Functions: Herbicide

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Knowde Enhanced TDS

Identification & Functionality

Agrochemical Functions
Technologies
Composition
ACTIVE INGREDIENT: % BY WT
Azadirachtin Isoxaben 0.50%
Dithiopyr 0.25%
OTHER INGREDIENTS 95.5%
TOTAL 100.0%

Features & Benefits

Product Highlights

Fortress contains 0.5% isoxaben and 0.25% dithiopyr on a dust-free granule.

  • Common Name: Isoxaben and Dithiopyr
  • Class: Benzamide and Pyridine

RESTRICTED ENTRY INTERVAL (REI) AND SIGNAL WORD

  • REI = 12 hours
  • Signal Word = CAUTION
Key Weeds Controlled

BROADLEAF WEEDS

  • aster, heath
  • bittercress
  • bittercress, little
  • bittercress, hairy
  • brassbuttons, southern
  • carpetweed
  • carrot, wild
  • chamber-bitter
  • chickweed, mouseear
  • dandelion
  • eclipta
  • galinsoga, hairy
  • geranium, Carolina
  • henbit
  • knotweed, prostrate
  • ladysthumb
  • Iespedeza, common
  • lettuce, prickly
  • mallow, common
  • marestail
  • mayweed, chamomile
  • medic, black
  • morningglory, ivyleaf
  • mustard
  • oxalis, buttercup
  • parsley-piert
  • pennywort
  • pigweed, redroot
  • Pineappleweed
  • plantain, bracted
  • plantain, broadleaf
  • plantain, buckhorn
  • pokeweed, common
  • purslane, common
  • rocket, London
  • rockpurslane, redmaids
  • sida, prickly
  • shepherdspurse
  • sorrell, red
  • speedwell, corn
  • speedwell, thymeleaf
  • spurge, garden
  • spurge, hyssop
  • spurge, prostrate
  • spurge, spotted
  • sweetclover, yellow
  • tansymustard, green
  • woodsorrel, creeping
  • woodsorrel, yellow

GRASSY WEEDS

  • barley
  • barnyardgrass
  • bluegrass, annual
  • brome
  • crabgrass, large
  • crabgrass, smooth
  • crabgrass, Southern
  • crowfootgrass
  • dallisgrass (seedling)
  • goosegrass
  • foxtail, green
  • foxtail, yellow
  • kikuyugrass
  • oats, wild
  • ryegrass (annual & perennial)
  • sandbur
  • smutgrass
List Of Crops
  • Abelia
  • Acacia
  • Agapanthus
  • Ash
  • Aster
  • Balsam fir
  • Barberry
  • Birch
  • Bougainvillea
  • Broom
  • Buxus
  • Camellia
  • Chrysanthemum
  • Crape myrtle
  • Coreopsis
  • Cotoneasters
  • Dogwoods
  • English ivy
  • Eunoymus
  • Ficus
  • Flowering dogwood
  • Gardenia
  • Heather
  • Hosta
  • Hollies
  • Ice plant
  • Japanese maple
  • Junipers
  • Leucothoe
  • Liriope
  • Magnolias
  • Mandevilla
  • Miscanthus
  • Mondo grass
  • Oaks
  • Osteospermum
  • Palms
  • Pennisetum
  • Pieris
  • Pines
  • Pittosporum
  • Plumbago
  • Privets
  • Redbud
  • Redwood
  • Rhododendron
  • Rudbeckia
  • Sago palm
  • Serviceberry
  • Spruce
  • Smoke tree
  • Yarrow

Applications & Uses

Mode Of Action

Fortress provides weed control by combining two modes of action, inhibition of both cellulose biosynthesis (MOA 21) and microtube assembly (MOA 3). These MOAs result in the inhibition of cell wall formation and mitotic processes in shoots and roots of emerging seedling weeds. The result is the prevention of weed seed emergence.

Use Sites

Fortress is registered for use in field and container ornamentals.

Application Rates

Apply Fortress herbicide at the rate of 150 lbs. per acre.

Directions For Use

IT IS A VIOLATION OF FEDERAL LAW TO USE THIS PRODUCT IN A MANNER INCONSISTENT WITH ITS LABELING.

Do not apply this product in a way that will contact workers or other persons. Only protected handlers may be in the area during application. For any requirements specific to your State or Tribe, consult the agency responsible for pesticide regulation

Agricultural Use Requirements

Use this product only in accordance with its labeling and the Worker Protection Standard, 40 CFR Part 170. This Standard contains requirements for the protection of agricultural workers on farms, forests, nurseries, and greenhouses, and handlers of agricultural pesticides. It contains requirements for training, decontamination, notification, and emergency assistance. It also contains specific instructions and exceptions pertaining to the statements on this label about personal protective equipment (PPE) and restricted-entry interval. The requirements in this box only apply to users of this product that are covered by the Worker Protection Standard. Do not enter or allow worker entry into treated areas during the restricted-entry interval (REI) of 12 hours. PPE required for early entry to treated areas that is permitted under the Worker Protection Standard and that involves contact with anything that has been treated, including plants, soil, or water is:

  • Coveralls
  • Waterproof gloves
  • Shoes plus socks
Non-Agricultural Use Requirements

The requirements in this box apply to uses of this product that are not within the scope of the Worker Protection Standard for agricultural pesticides (40 CFR Part 170). The WPS applies when this product is used to produce agricultural plants on farms, forest, nurseries, or greenhouses. Do not allow unprotected persons to enter treated areas until dusts have settled.

Technical Details & Test Data

Treatment

Treatment of ornamental species not listed on the label for Fortress

The species listed in the table aside have been tested under actual growing conditions and found tolerant at the recommended application rate. Users who wish to use Fortress on ornamental plant species not listed on the label may determine the suitability for use by treating a small number of such plants at the recommended rate. The user assumes responsibility for any plant damage or other liability resulting from use of Fortress on plant species not recommended on the label. Fortress has shown excellent grassy and broadleaf weed control in a number university tests. It is particularly good on crabgrass, bittercress and spurge, among other hard to control weeds. Shown in Fig.1 are 2017 test results from Dr. Andy Senesac, Cornell University. It shows the percent weed control at 30, 60 or 90 days after treatment respectively

Injury on the following plant species has been observed following applications of Fortress and use is not recommended.

  • Ajuga spp. bugleweed or ajuga
  • Brassica spp. mustard
  • Euonymus alatus ‘Compactus’ dwarf burning bush
  • Euphorbia spp. spurge
  • Hydrangea spp. hydrangea
  • Iberis spp. candytuft
  • Juniperus horizontalis ‘Prince of Wales’ Prince of Wales juniper
  • Melaleuca quinquenervia cajeput tree
  • Rhododendron carolinianum Carolina rhododendron
  • Rhododendron catawbiense ‘Roseum elegans’ roseum elegans rhododendron

Fortress® - Treatment

Safety & Health

Personal Protective Equipment (Ppe)
  • Long-sleeved shirt and long pants
  • Socks and shoes
  • Waterproof gloves
Precautionary Statements

HAZARDS TO HUMANS AND DOMESTIC ANIMALS

CAUTION

Harmful if absorbed through skin or inhaled. Causes moderate eye irritation. Avoid contact with skin, eyes, or clothing. Avoid breathing dust. Wash thoroughly with soap and water after handling and before eating, drinking, chewing gum, using tobacco, or using the toilet. Remove and wash contaminated clothing before reuse.

User Safety Recommendations
  • Remove clothing/PPE immediately if pesticide gets inside. Then wash thoroughly and put on clean clothing
  • Remove PPE immediately after handling this product. Wash the outside of gloves before removing. As soon as possible, wash thoroughly and change into clean clothing.
Environmental Hazards

This product is toxic to fish and highly toxic to other aquatic organisms including oysters and shrimp. Use with care when applying to turf areas adjacent to any body of water. Drift and runoff from treated turf may adversely affect aquatic organisms in adjacent aquatic sites. Do not apply directly to water, or to areas where surface water is present, or to intertidal areas below the mean high water mark. Do not apply when weather conditions favor drift from treated areas. Do not contaminate water when disposing of equipment washwaters.

Groundwater Advisory: This pesticide has properties and characteristics associated with chemicals detected in ground water. This chemical may leach into groundwater if used in areas where soils are permeable, particularly where the water table is shallow.

Surface Water Advisory: This pesticide may impact surface water quality due to runoff of rain water. This is especially true for poorly draining soil and soils with shallow groundwater. This product is classified as having a high potential for reaching surface water via runoff for several months or more after application. A level, well-maintained vegetative buffer strip between areas to which this product is applied and surface water features such as ponds, streams, and springs will reduce the potential loading of isoxaben from run off water and sediment

Packaging & Availability

Packaging Type
Packaging
  • 50 lbs. bags

Storage & Handling

Storage And Disposal

Do not contaminate water, food, or feed by storage or disposal

PESTICIDE STORAGE: Store in a clean, dry place. Store in original container and out of the reach of children, preferably in a locked storage area.

PESTICIDE DISPOSAL: Wastes resulting from the use of this product must be disposed of on site or at approved waste disposal facility.

CONTAINER HANDLING: Non-refillable container. Do not reuse or refill this container. Completely empty bag into application equipment. Then offer for recycling if available, or dispose in a sanitary landfill, or by incineration, or by other procedures allowed by State and local authorities.