Docket Number EPA-HQ-OPP-2009-0267; www.regulations.gov 

Interim Registration Review Decision Pesticide Re-evaluation Division Fosthiazate; Case 7604

I. INTRODUCTION

This document is the Environmental Protection Agency’s (EPA or the Agency) Interim 

Registration Review Decision for Fosthiazate and is being issued pursuant to 40 CFR sections 155.56 and 

155.58. A registration review decision is the Agency's determination whether a pesticide meets, or 

does not meet, the standard for registration in the Federal Insecticide, Fungicide, and Rodenticide 

Act (FIFRA). The Agency may issue, when it determines it to be appropriate, an interim registration 

review decision before completing a registration review. Among other things, the interim 

registration review decision may: 1) require new risk mitigation measures; 2) impose interim risk 

mitigation measures; 3) identify data or information required to complete the review; and 4) include 

schedules for submitting the required data, conducting the new risk assessment and completing the 

registration review. For further information on Fosthiazate, additional documents can be found in 

EPA’s public docket (EPA-HQ-OPP-2009-0267) at www.regulations.gov. 

FIFRA, as amended by the Food Quality Protection Act (FQPA) of 1996, mandated the 

continuous review of existing pesticides. All pesticides distributed or sold in the United States 

generally must be registered by the EPA based on scientific data showing that they will not cause 

unreasonable risks to human health or to the environment when used as directed on product 

labeling. The registration review program is intended to make sure that, as the ability to assess and 

reduce risk evolves and as policies and practices change, all registered pesticides continue to meet 

the statutory standard of no unreasonable adverse effects. Changes in science, public policy, and 

pesticide use practices will occur over time. Through the registration review program, the Agency 

periodically reevaluates pesticides to make sure that as these changes occur, products in the 

marketplace can continue to be used safely. Information on this program is provided as 

www.epa.gov/oppsrrd1/registration_review/.

In 2006, the Agency implemented the registration review program pursuant to FIFRA 

section 3(g) and will review each registered pesticide every 15 years to determine whether it 

continues to meet the FIFRA standard for registration. 

Fosthiazate was first registered as a pesticide in 2004, and therefore not subject to 

reregistration.

Pursuant to 40 CFR §155.50, the Agency formally initiated registration review for fosthiazate 

(case 7604). The following timeline highlights significant events that have occurred during the 

registration review of fosthiazate, and all associated documents can be found in the public docket 

(EPA-HQ-OPP-2009-0267, accessed at www.regulations.gov): 

 June 24, 2009 – The Agency published the Fosthiazate Summary Document, dated June 16, 2009 

for a 60-day public comment period. The Summary Document included the Agency’s 

Preliminary Work Plan for Fosthiazate. The Agency also posted the fosthiazate Preliminary 

Problem Formulation Document for the Ecological Risk Assessment and Drinking Water Exposure 

Assessment, and the Registration Review Scoping Document for Human Health Assessments. The 

Agency received one comment on the Fosthiazate registration review case, which provided 

chemical specific background data but did not result in any changes to the timeline or 

anticipated data needs.
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Interim Registration Review Decision Pesticide Re-evaluation Division Fosthiazate; Case 7604

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 December 10, 2009 – The Agency published the Fosthiazate Final Work Plan, which stated that 

the Agency would conduct a comprehensive ecological risk assessment and a human health 

risk assessment. 

 August 24, 2010 – The Agency issued the Generic Data Call-In for the registration review 

of fosthiazate, data requirements included: UV/visible absorption study (GLN 830.7050), 

and an immunotoxicity study (GLN 870.7800)

 March 20, 2013 – The Agency published the Preliminary Ecological Risk Assessment for the

Registration Review of Fosthiazate and the Fosthiazate Preliminary Human Health Risk Assessment for 

Registration Review, for a 60-day public comment period, the Agency received one comment 

during the comment period

 July 23, 2014 – The Agency published the Proposed Interim Registration Review Decision, for a 60-

day public comment period, in addition to supporting documents which included the Revised 

Fosthiazate: Human Health Risk Assessment for Registration Review, dated January 14, 2014 and the 

Response to Public Comments on the Preliminary Ecological Risk Assessment for Fosthiazate, dated

December 12, 2013. No comments were received during this public comment period.

 December 2014 - The Agency is now publishing the Fosthiazate Interim Registration 

Review Decision on regulations.gov under docket number EPA-HQ-OPP-2009-0267

Public Comments

Proposed Interim Decision:

No public comments were submitted to the Agency during the 60 day public comment 

period for the Fosthiazate Proposed Interim Registration Review Decision.

II. SCIENTIFIC ASSESSMENT

A. Human Health Risk Assessment

During the 60-day public comment period for the preliminary risk assessments, the technical 

registrant submitted additional occupational exposure information and data which was used in the 

development of the Revised Human Health Risk Assessment. A summary of the human health risk 

conclusions are presented below, for detailed information pertaining to the revised human health 

risk assessment, see the Revised Fosthiazate: Human Health Assessment for Registration Review (January 14, 

2014) in the public docket at EPA-HQ-OPP-2009-0267, which can be accessed through 

http://www.regulations.gov/. 

1. Risk Conclusions

No new information was received during the comment period for the preliminary risk 

assessments that informed the dietary assessment, and, as a consequence, dietary risk estimates for 
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fosthiazate have not been revised from the Agency’s preliminary risk assessment. Dietary exposure 

to fosthiazate (food + drinking water) to the most sensitive population subgroup, (all infants less 

than 1 year old), was estimated to be 15% of the acute population adjusted dose (aPAD) and 45% of 

the chronic population adjusted dose (cPAD), while for the general U.S. population fosthiazate 

exposure was estimated to be 5.6% of the aPAD and 19% of the cPAD. 

Since there are no registered residential uses of fosthiazate, no residential assessment was 

conducted. Consequently, the Agency did not perform an aggregate assessment where dietary (food 

+ drinking water) exposures are combined with exposure from residential exposure.

Occupational risk estimates were revised based upon information submitted by the technical 

registrant during the comment period on the preliminary risk assessments. The Agency updated the 

dermal toxicity endpoint by accounting for the difference in dermal penetration between the rat and 

human, and updating the inhalation toxicity endpoint by correcting the dose conversion, and by

adjusting the inhalation endpoint to a human equivalent concentration/dose (HEC). With these 

changes, the revised occupational assessment indicated no risks of concern. Potential risk from 

combined dermal and inhalation exposure is below the Agency’s level of concern, where the target 

aggregate risk index (ARI) is equal to or greater than 1 (ARI > 1), and the revised estimated ARI for 

fosthiazate is 3.7.

2. Human Incidents

At the time the Agency initiated the registration review of fosthiazate, a search for incidents 

was initiated within the Office of Pesticide Programs Incident Data System (IDS) was conducted. 

Available information between 2002 and 2009 was reviewed, and no human poisoning incident 

reports were identified for fosthiazate. No further review has been performed.

3. Cumulative

The Food Quality Protection Act (FQPA) requires the Agency to consider the cumulative 

risks of chemicals sharing a common mechanism of toxicity. Fosthiazate is a member of the 

organophosphate common mechanism group. The most recent cumulative risk assessment for the 

organophosphates was published on July 31, 2006 and is available at 

http://www.epa.gov/pesticides/cumulative/2006-op/op_cra_main.pdf.

4. Tolerances

The only U.S., tolerances established for fosthiazate are for tomatoes under 40 CFR 180.596. 

No CODEX, Canadian, or Mexican maximum residue limits (MRLs) have been established for 

fosthiazate. No change to the U.S. tolerance is being sought for fosthiazate during registration 

review.

B. Environmental Risk Assessment

During the 60-day public comment period for the preliminary risk assessments, the technical 

registrant submitted additional effects and exposure data on terrestrial invertebrates which modified 

the Agency’s assessment for this taxa. During the registration review of fosthiazate, the Agency 

identified no risk concerns for aquatic animals or plants from fosthiazate. However, potential risks 
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were identified for birds, terrestrial mammals and terrestrial invertebrates. A summary of ecological 

risk conclusions for fosthiazate is presented below. For detailed discussion of all aspects of the 

environmental risk assessment, see the Preliminary Ecological Risk Assessment for the Registration Review of 

Fosthiazate, dated March 11, 2013, and the Response to Public Comments on the Preliminary Ecological Risk 

Assessment for Fosthiazate, dated December 12, 2013, in the public docket EPA-HQ-OPP-2009-0267, 

which can be accessed through http://www.regulations.gov/. 

The Agency also completed a screening-level threatened and endangered (listed) species 

assessment for fosthiazate and identified potential risks to several taxa (birds, mammals and 

terrestrial invertebrates). The Agency is currently working with its federal counterparts and other 

stakeholders to implement an interim approach for assessing potential risk to listed species and their 

designated critical habitats. Once, the scientific methods necessary to complete risk assessments for 

listed species and their designated critical habitats are finalized, the Agency will complete its listed 

species assessment for fosthiazate. As such, only screening-level risks to listed species will be 

enumerated here. Risk to listed species will not be characterized herein.

1. Ecological Exposure and Risk Conclusions 

Environmental fate information available to the Agency indicates that fosthiazate is 

both persistent and mobile. However, due to the application method of fosthiazate, by drip 

irrigation under a plastic mulch, potential movement of fosthiazate into the terrestrial 

environment beyond the site of application is also limited. Likewise, the potential for 

fosthiazate to move into surface water or groundwater is also limited. 

Birds and Mammals:

Potential exposure to fosthiazate for birds and mammals comes from consuming either 

contaminated arthropods or contaminated earthworms. Risk quotient (RQ) estimates ranged 

depending upon the weight of the bird or the environmental fate parameters used to estimate RQs. 

For birds only acute level of concern (LOC) exceedances were identified, and for mammals only 

chronic LOC exceedances were identified. Acute RQs for birds that may consume contaminated 

arthropods range from 0.11 to 0.25, which exceed the LOC for listed species but does not exceed 

the LOC for non-listed species (Appendix A below provides the LOCs for non-listed and listed 

species for ecological risk assessment). Acute RQs for birds that may consume contaminated 

earthworms range from 0.2 to 0.98 (which exceed LOCs for both listed as well as non-listed 

species). Chronic RQs for mammals that may consume contaminated arthropods range from 1.26 

to 1.48, and chronic RQs for mammals that may consume contaminated earthworms range from 

1.16 to 5.7, which exceeds the Agency’s LOC.

Terrestrial Invertebrates:

Since fosthiazate is a systemic insecticide and applied to the soil via drip irrigation, potential 

contact and oral exposure to terrestrial invertebrates can occur. RQs were estimated for those 

organisms that are soil-bound (utilizing acute contact data) and for those that are not soil-bound, 

such as bees (utilizing acute oral data that were submitted during the initial public comment period). 

An acute RQ for soil- bound terrestrial invertebrates was estimated to be 6.9 (which exceeds the 

LOC). The acute RQ for terrestrial invertebrates which are not soil-bound is below the LOC.
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2. Ecological Incidents

At the time the Agency initiated the registration review of fosthiazate (2009), a review of the 

Office of Pesticide Programs Ecological Incident Information System (EIIS,) was conducted for 

fosthiazate related adverse incident information. No adverse effect reports were found that were 

attributed to fosthiazate. Again, in 2012, a review of EIIS, as well as a review of the Avian Incident 

Monitoring System (AIMS), and the Incident Data System (IDS) was conducted to search for any 

fosthiazate related adverse incident information. In general, the Agency believes that the lack of 

ecological incident reports does not necessarily indicate a lack of incidents but rather could be lack 

of reporting. In the case of fosthiazate, the lack of incidents may also be attributed to its lack of use.

3. Risk Characterization

Ecological risk estimates for fosthiazate represent screening-level analysis where the Agency 

uses reasonable worst-case scenarios and conservative assumptions with the intention that estimates 

do not underestimate risk. Because non-standard methods were used to estimate risk to certain taxa, 

e.g., soil-bound invertebrates, the Agency presented risk ranges and conducted additional modeling 

to estimate RQs.

The Agency considers the exposure estimates, and therefore risk estimates, for birds and 

mammals to be conservative for a number of reasons. When the Agency estimated dietary exposure 

to birds and mammals via consumption of contaminated earthworms and arthropods, the Agency 

assumed that the dose received by the bird/mammal via the contaminated article (the arthropod or 

earthworm) is equal to the concentration of fosthiazate applied to the soil. It is likely however, that 

avian/mammalian food sources in the soil do not reach equilibrium with the concentration of the 

pesticide in the soil. In addition, the limited availability of the contaminated food source was not 

accounted for in the fosthiazate exposure assessment. That is, since fosthiazate is applied under 

plastic tarp, the bird or mammal would have to puncture the plastic tarp to access the contaminated 

food source, an aspect of exposure that the Agency acknowledges but for which it cannot 

quantitatively account. Instead, the Agency's assessment assumes that an organism's entire diet (i.e., 

bird or mammal) for one day consists solely of the contaminated food article. Additionally, with 

respect to estimated risk to terrestrial soil-bound invertebrates, risk to these taxa have also been 

conservatively estimated because with the drip irrigation application method, the distribution of the 

compound throughout the soil is both targeted and limited to the root zone of the plant resource to 

be protected (tomatoes) from the target pest (nematodes). Therefore, while estimated risks to soildwelling invertebrates may exist, the risk is likely to be limited to those organisms directly in the root 

zone, and less so to organisms that may be in the areas between plants or within furrows.

C. Endangered Species Assessment

In November 2013, the EPA, along with the U.S. Fish & Wildlife Service (USFWS), the 

National Marine Fisheries Service (NMFS) (collectively, the Services), and the U.S. Department of 

Agriculture (USDA) released a summary of their joint Interim Approaches for assessing risks to 

listed species from pesticides. The Interim Approaches were developed jointly by the agencies in 

response to the National Academy of Sciences' (NAS) recommendations and reflect a common 

approach to risk assessment shared by the agencies as a way of addressing scientific differences 

between the EPA and the Services. The AS report outlines recommendations on specific scientific 
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and technical issues related to the development of pesticide risk assessments that EPA and the 

Services must conduct in connection with their obligations under the Endangered Species Act (ESA) 

and FIFRA.

The joint Interim Approaches were released prior to a stakeholder workshop held on 

November 15, 2013. In addition, the EPA presented the joint Interim Approaches at the December 

2013 Pesticide Program Dialogue Committee (PPDC) and State-FIFRA Issues Research and 

Evaluation Group (SFIREG) meetings, and held a stakeholder workshop in April 2014, allowing 

additional opportunities for stakeholders to comment on the Interim Approaches. As part of a 

phased, iterative process for developing the Interim Approaches, the agencies will also consider 

public comments on the Interim Approaches in connection with the development of upcoming 

Registration Review decisions. The details of the joint Interim Approaches are contained in the

white paper "Interim Approaches for National-Level Pesticide Endangered Species Act 

Assessments Based on the Recommendations of the National Academy of Sciences April 2013 

Report," dated November 1, 2013.

Given that the agencies are continuing to develop and work toward implementation of the 

Interim Approaches to assess the potential risks of pesticides to listed species and their designated 

critical habitat, the ecological risk assessment supporting this Interim Registration Review Decision 

for fosthiazate does not contain a complete ESA analysis that includes effects determinations for 

specific listed species or designated critical habitat. Although EPA has not yet completed effects 

determinations for specific species or habitats, for this preliminary assessment EPA conducted a 

screening-level assessment for all taxa of non-target wildlife and plants that assumes for the sake of 

the assessment that listed species and designated critical habitats may be present in the vicinity of the 

application of fosthiazate. This screening-level assessment will allow EPA to focus its future 

evaluations on the types of species where the potential for effects exists once the scientific methods 

being developed by the agencies have been fully vetted. Once the agencies have fully developed and 

implemented the scientific methods necessary to complete risk assessments for endangered and 

threatened (listed) species and their designated critical habitats, these methods will be applied to 

subsequent analyses for fosthiazate as part of completing this registration review.

D. Endocrine Disruptor Screening Program

As required by FIFRA and the Federal Food Drug and Cosmetic Act (FFDCA), EPA 

reviews numerous studies to assess potential adverse outcomes from exposure to chemicals. 

Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of 

carcinogenicity, neurotoxicity, developmental, reproductive, and general or systemic toxicity. These 

studies include endpoints that may be susceptible to endocrine influence, including effects on 

endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, 

pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, 

EPA evaluates acute tests and chronic studies that assess growth, developmental and reproductive 

effects in different taxonomic groups. As part of its most recent registration decision for 

fosthiazate, EPA reviewed these data and selected the most sensitive endpoints for relevant risk 

assessment scenarios from the existing hazard database. However, as required by FFDCA section

408(p), fosthiazate is subject to the endocrine screening part of the Endocrine Disrupter Screening

Program (EDSP).
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EPA has developed the EDSP to determine whether certain substances (including pesticides 

and other active ingredients) may have an effect in humans or wildlife similar to an effect produced 

by a "naturally occurring estrogen, or other such endocrine effects as the Administrator may 

designate." The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or 1) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to interact 

with E, A, or T hormonal systems will proceed to the next stage of the EDSP where EPA will 

determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 testing is 

designed to identify any adverse endocrine-related effects caused by the substance, and establish a 

dose-response relationship between the dose and the E, A, or T effect.

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, EPA issued test orders/data call-ins for the first group of 67

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list of 

chemicals identified for EDSP screening was published on June 14, 20131 and includes some 

pesticides scheduled for registration review and chemicals found in water. Neither of these lists 

should be construed as a list of known or likely endocrine disrupters.

Fosthiazate is not among the compounds on either list one or list two. In the interim, EPA 

is making no human health or environmental safety findings associated with the EDSP screening of 

fosthiazate. Before completing this registration review, the Agency will make an EDSP FFDCA 

section 408(p) determination.

III. USE AND USAGE

Fosthiazate is an organophosphate (OP) nematicide registered for use only on tomatoes; it is 

formulated as an emulsifiable concentrate and applied via drip irrigation under plastic mulch prior to 

insertion of tomato transplants into the bed. There are two registrations for fosthiazate, one 

technical product, and one end-use product. The Agency has found no data indicating use of 

fosthiazate in the U.S. Based upon comments submitted by the technical registrant (ISK 

Bioscience), the marketing of fosthiazate was intended to represent a soil sterilization option for 

growers as the availability of methyl bromide and other soil fumigants decreased. However, 

fosthiazate would only be a selective replacement, as it is intended to mainly control nematodes, 

such as root-knot nematode (Meloidogyne incognita), or spiral nematode (Helicotylenchus spp.), and is not 

effective in controlling weeds or soil pathogens. ISK believes that any future use of fosthiazate 

would likely be in conjunction with integrated pest management (IPM) programs for crops where 

control of nematodes is necessary (ISK submission, Fosthiazate: Methyl Bromide Replacement and Reduced 

Risk Status, Oct. 18, 1999)

IV. INTERIM REGISTRATION REVIEW DECISION

A. Tolerance Amendments

No tolerance changes for fosthiazate are recommended as part of the fosthiazate registration 

Review process. 
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B. Risk Mitigation Measures and Rationale

Based upon (i) the Agency's risk analysis incorporates a number of conservative exposure 

elements; (ii) there are no reported adverse incidents associated with fosthiazate; and, (iii) estimated 

risk from fosthiazate to birds and mammals range from below the LOCs to slightly above the LOCs, 

(depending upon the assumptions employed), the Agency believes that any ecological risks from 

fosthiazate are low, and as noted in the ecological risk assessment, are restricted only to the 

application site. As noted earlier, the Agency has no information indicating use of fosthiazate and 

therefore, benefits of fosthiazate are considered to be low.

In order to reduce potential ecological risks, fosthiazate labels must be changed to increase 

the minimum irrigation volume from the current 0.5 - 1 inches of water per acre to 1.25 inches of 

water per acre. Increasing the volume of irrigation water per acre will reduce the concentration of 

fosthiazate in the soil, and therefore potential exposure to all non-target organisms, including birds 

and mammals that may eat contaminated arthropods or earthworms, soil-dwelling invertebrates and 

other terrestrial invertebrates (such as bees).

Increasing the required volume of water to 1.25 inches per acre, will:

o reduce estimated acute risks to birds, and chronic risk to mammals that consume 

arthropods to below the listed LOC.

o reduce the estimated acute risk to birds and chronic risk to mammals that consume 

earthworms, but not likely below the listed LOC.

o reduce estimated risks to soil-dwelling invertebrates, but not below LOCs.

C. Interim Registration Review Decision

In accordance with 40 CFR Sections 155.56 and 155.58, the Agency is issuing this Interim 

Registration Review Decision. Except for the EDSP and ESA components in this case, the Agency 

has made the following Interim Registration Review Decision: (1) no additional data are required at 

this time; and (2) changes to the affected registrations and their labeling are needed at this time (see 

Appendix C: Fosthiazate Label Table).

In this Fosthiazate Interim Registration Review Decision, EPA is making no human health 

or environmental safety findings associated with the EDSP screening of fosthiazate, nor is it making 

a complete endangered species finding. The Agency's final registration review decision for 

fosthiazate will be issued once ESA Section 7 Endangered Species consultation with the Services has 

taken place, and an EDSP FFDCA section 408(p) determination has been made.

V. NEXT STEPS AND TIMELINE

A. Implementation of Mitigation Measures

The registrant must submit amended labels that include the risk mitigation described in this 

interim decision to the Agency for approval within 60 days following the issuance of this Interim 
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Interim Registration Review Decision Pesticide Re-evaluation Division Fosthiazate; Case 7604

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Registration Review Decision. Mitigation measures are described in Appendix B, and changes to 

labels are described in Appendix C.

B. Final Registration Review Decision

EPA will make a final registration review decision for fosthiazate after ESA Section 7 

consultation with the Services is completed and an EDSP FFDCA section 408(p) determination has 

been made.
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Appendix A: Levels of Concern (LOC) for Ecological Risk Assessment

Taxa Non-Listed Species LOC Listed Species LOC 

Acute Chronic

Birds and Wild Mammals ! 0.5 1 0.1 

Aquatic Animals 0.5 1 0.05

Plants I 1 1 1

Terrestrial Invertebrates 0.4 1 0.05 (interim)

I

Appendix B: Summary of Mitigation for Fosthiazate

Registration Review Case#: 7604

Chemical Name: Fosthiazate

PC Code: 129022

Chemical Type: Nematicide

Chemical Family: Organophosphate

Mode of Action: Cholinesterase (ChE) Inhalation

IM_odc of Action: Cholinesterase (ChE) Inhibition

Birds Contaminated 

arthropods

Route of

Exposure

Duration of

Exposure

Risk(s) of Concern Mitigation

Birds Contaminated

arthropods

Dietary acute Estimated RQs range from 

below LOC to 0.25

Increase the minimum irrigation 

volume from the current 0.5 - 1 

inches of water per acre to 1.25 

inches of water per acre

Birds Contaminated

earthworms

Dietary acute Estimated RQs from below

LOC to 0.98

Increase the minimum irrigation 

volume from the current 0.5 - 1 

inches of water per acre to 1.25 

inches of water per acre

Mammals Contaminated

arthropods

Dietary chronic Estimated RQs range from

below LOC to 1.48

Increase the minimum irrigation 

volume from the current 0.5 - 1 

inches of water per acre to 1.25 

inches of water per acre

Mammals Contaminated

earthworms

Dietary chronic Estimated RQs range from

below LOC to 5.71

Increase the minimum irrigation 

volume from the current 0.5 - 1 

inches of water per acre to 1.25 

inches of water per acre

Soil-dwelling 

invertebrates

Contamination of its 

environment by drip 

irrigation

Dietary/contact acute Estimated RQ = 6.9 Increase the minimum irrigation 

volume from the current 0.5 - 1 

inches of water per acre to 1.25 

inches of water per acre
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Appendix C: Fosthiazate Label Table

Summary of Labeling Changes for Fosthiazate Uses

Description Amended Labeling Language for Fosthiazate Use Products Placement on Label

End Use Products

Current Label

Language Change

Current:

Use sufficient water to allow thorough incorporation throughout the bed to achieve, 

efficacy, but not cause run cause runoff or excessive leaching. In most soils, 1/2 to 1 

inch of irrigation water/A is required for incorporation of the product when applied 

through a drip irrigation system.

Change to:

Use sufficient water to allow thorough incorporation throughout the bed to achieve

efficacy, but not cause runoff or excessive leaching. Use of 1.25 inches of irrigation 

water/A is required for incorporation of the product when applied through a drip 

irrigation system.

Directions for Use