Fire Blight of Apple and Pear

 by Tianna DuPont, Associate Professor, Washington State University; Tim Smith, Washington State University Tree Fruit Extension Specialist Emeritus; Ken Johnson, Professor of Plant Pathology Oregon State University; Youfu Zhao, Washington State University. Updated April 13, 2023.

Fire blight is an important disease affecting pear and apple. Infections commonly occur during bloom or on late blooms during the three weeks following petal fall. Increased acreage of highly susceptible apple varieties on highly susceptible rootstocks has increased the danger that infected blocks will suffer significant damage. In Washington there have been minor outbreaks annually since 1991 and serious damage in about 5 to 10 percent of orchards in 1993, 1997, 1998, 2005, 2009, 2012, 2015, 2016, 2017 and 2018.

Casual Organism

Fire blight is caused by Erwinia amylovora, a gram-negative, rod-shaped bacterium. The bacterium grows by splitting its cells and this rate of division is regulated by temperature. Cell division is minimal below 50° F, and relatively slow at air temperatures between 50 to 70° F.  At air temperatures above 70° F, the rate of cell division increases rapidly and is fastest at 80° F. Above 95° F cell density on and in the plant can actually decline (Pusey and Curry 2004).

Host Range

Considered a problem for apple and pear, E. amylovora has a wide host range within Rosacea and Rubus with reports on about 200 species including crab apple, hawthorn, mountain ash and Bradford pear (Momol and Aldwincklke 2000).

Signs and Symptoms

 

Transmission and Disease Cycle

Erwinia amylovora overwinters in the living tissue around canker margins (Biggs 1994, Teviotdale 2011). In 7 to 62% of cankers active cells survive the winter (van der Zwet and Beer 1991, Santander et al. 2022) and when humidity is high in the spring the pathogen ooz.es out of these cankers (Figure 5). This ooz.e is attractive to bees, flies and other insects who transfer the blight pathogen to flowers (Van Der Zwet and Keil 1979). Pathogen cells can also be moved from old cankers to flowers by splashed and wind-blown rain. Pathogen cells multiply quickly on nutrient rich floral stigma when temperatures are warm (70 to 80° F is optimal for the pathogen) (Ogawa and English 1991, Pusey and Curry 2004). Bacterial cells can then be washed down the style into the floral cup by water (usually from rain or heavy dew) where they can invade flowers through the nectaries (Thomson 1986). Once initial blossoms are infested, ooze droplets form with as many as a billion bacterial cells per droplet (Slack et al. 2017). Insects and rain can move the pathogen to additional flowers (Johnson et al. 1993, Pattemore et al. 2014). If the pathogen is successful in infecting the developing fruitlet, the disease spreads through the intercellular spaces and then the vascular system of the tree (xylem) (Momol et al. 1998). It kills young host tissues as it progresses creating characteristic strikes and cankers. Pathogen cells migrate inside the tree well ahead of visible symptoms where they can accumulate in other susceptible tissue such as one-year old shoot tips and susceptible rootstocks causing infections distant from the original infection (Bogs et al. 1998). For example, in a Michigan study, fire blight bacteria moved an average of 6 cm per day in new growth and 4 cm per day in woody growth in five-year-old Gala, which equates to approximately 11 inches per week (Olive et al. unpublished).

Erwinia amylovora can also infect susceptible one- and two-year-old tissue directly through wounds (e.g. insect feeding and hail) and natural openings causing shoot blight infections (Vannesta 2000, Millet 2022).

Cultural Controls

Plant on resistant rootstock

Resistant rootstocks (e.g. Geneva series for apples) do not make the scion less susceptible, but will help prevent tree death from rootstock blight.

Winter sanitation

In winter, prune out old blight cankers as thoroughly as possible. Ideally, cut blight before you prune for tree structure so that the blighted cuttings can be removed from the orchard. Compared to cuts made in summer, winter removal cuts can be made closer to the visible canker edge. In winter the pathogen is confined to the cankered area. Cut at the next “horticulturally sensible” site below the canker. You do not need to sterilize tools when you are cutting on fully dormant trees. Late dormant copper applications can enhance orchard sanitation, further reducing inoculum levels going into spring (Elkins et al. 2015).

Manage the orchard environment

In addition to warm temperatures, moisture is required to initiate infections. As little as two to three hours of wetting from dew or light rain is sufficient to trigger infection. Manage weeds and cover crops to limit relative humidity. Do not irrigate during bloom.

Blossom removal in young blocks

Blossom removal in young blocks and removal of late blooms limits the numbers of flowers and thus reduces potential points of infection. In two 2020 trials flower removal at pink for young non-bearing trees reduced infections to 0 compared to 71-77 per 100 clusters in water treated checks and 5-17 per 100 clusters in soluble copper treated trees (DuPont 2022).

Keep tree vigor moderate

Moderating vigor will not prevent infection, but it can reduce damage to the tree by limiting the amount of new and more susceptible plant growth.

Temperature Risk Models

The risk of fire blight infections during bloom can be calculated based on the temperature and moisture. In Washington the best prediction model is Cougar Blight available at WSU Decision Aid System for Tree Fruit (DAS). This model calculates fire blight risk based on the temperature of the previous four days using the documented growth rate of the bacteria, e.g. higher risk with multiple hours above 70° F (Pusey and Curry 2004). The model then projects risk for the next three days based on predicted temperatures. Growers can use model information to decide when to spray. If trees are likely to be blooming during an upcoming high-risk period, protective sprays are recommended (Smith and Pusey 2010).

Chemical Controls

Chemical Control Programs

There is a risk of fire blight infection any time there are flowers on the tree, the weather is warm, and wetting occurs. Watch for and protect secondary blossoms during the three weeks after petal fall, a common time for fire blight infection. Most sprays only protect the blooms that are open. Protect new blooms as they open. In warm weather follow-up sprays are needed every 2 to 3  days rotating FRAC.

Conventional Management

Watch the model. After a period of warm weather (high infection risk) best results are obtained when antibiotics are applied within the 24-hour window before flower wetting. Products used must contact the interior of the flowers in sufficient water and approved wetting agent to completely cover the interior. Antibiotic sprays every 2 to 3 days may be necessary during extended high or extreme risk periods. Rotate between materials with differing mode of action (FRAC). In high risk blocks or if fire blight was in the orchard last year consider applications of Blossom Protect during early bloom. Lime sulfur applications used for thinning are also antimicrobial and reduce blight pressure. See Tables 1 and 2.

Organic Management

Non-antibiotic control programs for fire blight which contain Blossom Protect and soluble copper products during the bloom period (e.g. Previsto, Cueva) followed by Bacillus based biorationals (e.g. Serenade Opti) at petal fall have performed well suppressing fire blight infections with lower russet risk in Oregon trials 2013 to 2021 (Johnson et al. 2022) as well as Washington and New York (Cox et al. 2015, Cox et al. 2016, DuPont et al. 2023). In difficult-to-thin apple varieties, with multiple lime sulfur applications, soluble coppers may fit better in control programs than Blossom Protect whose population is impacted by lime sulfur applications. Integrated programs with Blossom Protect and/or soluble coppers during high-risk bloom periods followed by essential oils or peracetic acid-peroxide products (e.g. Thyme Guard, Cinnerate, Oxidate 5.0, Jet Ag) at petal fall have also had control similar to Blossom Protect/Serenade programs in several trials (DuPont et. al 2023). Consider drying times, rotations, and limit post petal fall applications of essential oils and peracetic acid-peroxides products to moderate russet risk. See Tables 1 and 2.

Non-bearing trees

Young non-bearing trees with high vigor in high-risk varieties or locations may require season-long protection from shoot blight. In recent trials for protection of young non-bearing trees lower removal performed best followed by weekly applications of soluble copper at 3 to 4 qt. per acre or fixed copper at 1.5 lb. per acre (DuPont 2022). Flower removal at pink for young non-bearing trees reduced infections to 0 infections per 100 clusters in PA and 0 per 100 in New York in 2020 trials. Three applications of soluble copper (Previsto 3 qt., or Cueva 4 qt.) reduced infections per 100 clusters from 77 to 5.5 in New York, and 71 to 17 in Pennsylvania and three applications of fixed copper (1.5 lb.) reduced infections per 100 clusters from 77 to 27 in New York and 71 to 8 in Pennsylvania.

Example plans for different blocks and conditions

A grower might choose from one of these plans for different blocks and conditions.

^a Remember Blossom Protect yeast need about 12 hours to grow on the flower to protect blooms before a wetting event.

^b Spray tank acidification has been most significant for oxytetracycline products (e.g. Mycoshield).

^c Lime sulfur at this timing can interfere with oil sprays for mites.

^d Rotate. Rotation is necessary for resistance. Rotate as necessary to comply with application intervals for individual products. Do not apply Actigard at closer than 7-day interval (label restriction).

^e Kasumin. Do not make more than 4 applications of KASUMIN 2L per year. Post petal fall restriction has been removed (March 2021).

^f Blossom Protect+ Buffer Protect, then Previsto (full bloom), then Serenade Opti/Aso (petal fall) best organic combination in 13 trials in Oregon at 83% relative control (Johnson) similar to antibiotics.

^g Remember Blossom Protect yeast need about 12 hours to grow on the flower to protect blooms before a wetting event.

^a Remember Blossom Protect yeast need about 12 hours to grow on the flower to protect blooms before a wetting event.

^b Spray tank acidification has been most significant for oxytetracycline products (e.g., Mycoshield).

^c Lime sulfur at this timing can interfere with oil sprays for mites.

^d Rotate. Rotation is necessary for resistance. Rotate as necessary to comply with application intervals for individual products. Do not apply Actigard at closer than 7-day interval (label restriction).

^e Kasumin. Do not make more than 4 applications of KASUMIN 2L per year. Post petal fall restriction has been removed (March 2021).

Antibiotic Resistance Management

Fire blight pathogen resistance to streptomycin was first detected in California in 1971 and in Oregon and Washington in the 1970s and 1980s (Coyier and Covey 1975). It was believed to be widespread in the western United States in 1991 and in other parts of the US including Idaho, Utah, Missouri, Michigan (2003) and New York (2002, 2016, 2021) (Loper et al. 1991a, McGhee and Sundin 2011, Forster et al. 2015a, Tancos et al. 2016). In an ongoing survey in Washington none of the bacterial populations screened exhibited resistance to streptomycin, tetracycline or kasugamycin (Zhao et al. unpublished). To minimize the risk of resistance development, it is recommended to apply streptomycin in combination with oxytetracycline and limit streptomycin application to once per season. Kasugamycin could be applied in a mixture with oxytetracycline or rotation with oxytetracycline.

Strategies for Improving Protective Programs

Coverage

Product efficacy is based on thorough coverage of flowers. Use tree row volume to apply appropriate volumes to cover the tree architecture in your orchard. Products applied every other row or at high speeds may have insufficient coverage and lower efficacy.

Timing

Antibiotics have the highest efficacy when applied shortly before a moisture event. Nonetheless, kasugamycin and streptomycin can also be applied up to 12 hours after a moisture event, but with reduced effectiveness. Streptomycin has locally systemic activity and kasugamycin is effective on bacteria which have been washed into the floral cup but not yet invaded the flower.

pH of Spray Tank Water

It is important to appropriately acidify spray tank water when using antibiotics (especially oxytetracycline and kasugamycin). Antibiotic efficacy reported in WSU trials is with spray tank water buffered to pH 5.6. At higher pHs antibiotic degradation rate is faster and thus efficacy is often lower. For example, in one trial kasugamycin reduced the bacterial population by 86% to 96% at pH 5.1 but only 21% to 35% at pH 7.3 (Adaskaveg et al. 2011). Johnson and KC (2021) found that buffering oxytetracycline products to a pH of 4 can further improve efficacy.

Use Appropriate Rates

Quantity of active ingredient is important to obtain efficacy. For example, recent work looking at rates of copper products demonstrated that as metallic copper content increases, copper product efficacy increases up to approximately 0.2 lb. metallic copper per 100 gal per acre (DuPont 2019) (Figure 7). This is equivalent to approximately 3 qt. of Previsto or 4 qt. of Cueva.

Mixtures

A full rate of kasugamycin (100 ppm) with a full rate of oxytetracycline (200 ppm), as well as streptomycin (100 ppm) mixed with a full rate of oxytetracycline (200 ppm) have provided improved efficacy in some trials (Oregon 2015-2018) (Johnson, K. unpublished). Actigard (2 oz. per 100 gal.) plus an antibiotic applied during bloom has improved the efficacy of antibiotics an average of 5% to 6% per ASM treatment in trials in Washington and Oregon (Johnson et al. 2016).

Antibiotics

Kasugamycin (Kasumin) is a recently labeled antibiotic that provides excellent levels of control. For example in eight trials in Michigan relative control averaged 92% (Sundin and McGhee 2010). All fire blight strains are currently sensitive to this material but there is an intermediate risk of resistance developing to this antibiotic (Adaskaveg et al. 2011). Kasumin controls streptomycin-resistant strains of fire blight. Kasumin provides forward control for two to three days prior to rain events (on flowers open when applied) and will be partially effective for blossom blight control if applied within 12 hours after a rain event. Kasumin is not locally systemic like streptomycin. Thus, Kasumin will not penetrate into the nectaries and will not be able to control an infection once the fire blight pathogen reaches the nectaries. Acidifying spray tanks (target 5) is important to reduce antibiotic break down and extend activity. Kasugamycin is ultraviolet (UV) sensitive and spraying at night and reduced pH can help improve residual time. The use of a non-ionic surfactant enhances deposition of the antibiotic on flowers.

Oxytetracycline (Mycoshield, FireLine) generally provides good levels of control in Washington trials (average 74% control) and has a low risk of resistance development (DuPont et al. 2023). Oxytetracycline products should be applied within 12 to 24 hours prior to a moisture event for best results. Oxytetracycline is considered bacteriostatic (inhibits bacterial growth). Thus, to be effective it must be applied prior to rains where it can prevent growth on stigmas. Oxytetracycline is also sensitive to UV degradation and much of the activity is lost within one to two days after application. Acidifying spray tanks (target 5) is important to reduce antibiotic break down and extend activity. The use of a non-ionic surfactant enhances deposition of the antibiotic on flowers.

Streptomycin (Agri-Mycin, FireWall): Streptomycin-resistant strains of the fire blight pathogen have been present in Washington orchards since 1975 (Coyier and Covey 1975, Loper et al. 1991b). Recent tests have indicated that the proportion of the pathogen population resistant to this antibiotic has dropped and expected control levels have improved (Forster et al. 2015b). In an ongoing survey in Washington no fire blight strains resistant to streptomycin were detected (Zhao 2023). This product should only be used in combination with oxytetracycline and should not be used unless a high-to-extreme risk infection period is expected. Limit use to once per season. The use of a non-ionic surfactant enhances deposition of the antibiotic on flowers. Acidifying spray tanks (target 5) is important to reduce antibiotic break down and extend activity.

Non-Antibiotic Products

In summary analysis of eight Washington trials Alum (potassium aluminum sulfate), Blossom Protect (A. pullulans) and several copper products (Previsto, Mastercop, Instill) provided good disease suppression of 70% to 73% similar to antibiotic checks (DuPont et al. 2023) (Figure 9). Several essential oil, copper, peracetic acid-peroxide and biological products (Serenade Opti, Cueva, Oxidate 5.0, Jet Ag, Thyme Guard, Thymox and Cinnerate) provided intermediate disease suppression between 45% to 62% significantly better than the water-treated control.

*Important! Some of the pesticides discussed in this presentation were tested under an experimental use permit granted by WSDA. Application of a pesticide to a crop or site that is not on the label is a violation of pesticide law and may subject the applicator to civil penalties up to $7,500. In addition, such an application may also result in illegal residues that could subject the crop to seizure or embargo action by WSDA and/or the U.S. Food and Drug Administration. It is your responsibility to check the label before using the product to ensure lawful use and obtain all necessary permits in advance.

Blossom Protect

Blossom Protect is a combination of two strains of Aureobasidium pullulans, a yeast that occurs naturally in the Pacific Northwest pome fruit flowers applied in combination with a buffer, Buffer Protect. Relative efficacy of Blossom Protect plus Buffer Protect in Washington averaged 72% across six orchard trials with two to three applications (DuPont et al. 2023). High relative efficacy has also been documented in Oregon with control comparable to antibiotic standards, in Michigan where two applications resulted in between 85% and 92% relative control, and in Germany where Blossom Protect provided an average of 79% efficacy across 11 trials (Kunz et al. 2011, Johnson and Temple 2013a, Sundin et al. 2018, Outwater et al. 2019).

Recommendations for Blossom Protect use include applications to every tree row (Temple et al. 2020). It may also be important to apply with at least 12 to 24 hours between application and an impending rain event in order to give sufficient time for A. pullulans populations to colonize flowers (Temple et al. 2020).

Coppers

Coppers are generally effective disease control products. Free copper ions are taken up by cells and cause toxicity by non-selectively denaturing proteins in cells. New soluble copper formulations are designed to have lower plant phytotoxicity. For example, copper octanoate (Cueva) is a copper soap, copper hydroxide product (Previsto) is formulated with a polymer matrix designed to lessen toxicity of copper ions on the plant surface, and copper sulfate pentahydrate products (e.g. Instill) are generally highly soluble but may be formulated to reduce plant phytotoxicity. Soluble coppers are used during bloom in semi-arid Washington but can cause phytotoxicity in wetter areas in Oregon and California (Smith 2012, 2015, Johnson 2016). In Washington trials relative disease suppression for soluble coppers (Previsto, Instill, Mastercop, Cueva) ranged from a median of 47% to 73% in 2013 to 2022 trials (DuPont et al. 2023). These results are similar to field trials from other regions of the United States, such as New York, Virginia, and Oregon, where soluble coppers provided between 50% and 80% relative control, varying depending on type, timing, and rate of application (Yoder et al. 2013, Cox et al. 2014, Choi et al. 2018, DeShields and DeShields 2020). The amount of metallic copper in a product will determine in part the appropriate rate for optimum efficacy. Analysis based on metallic copper content of copper products combined over multiple years and products indicates an optimum range of metallic copper application for fire blight control between 0.16 and 0.25 lb. per 100 gal. per acre of metallic copper equivalent (p<0.001; R²=0.46) (DuPont 2019) (Figure 7). Concern about fire blight resistance to coppers has been raised due in part to resistance documented in Pseudomonas syringae strains affecting almonds (Andersen et al. 1991). However, none of 138 isolates tested in Washington in 1991 by Loper et al. (1991a) grew in copper at 0.16 mM and while 15 of 80 isolates in nearby British Columbia, Canada had a reduced response at 0.16 mM, no tolerance was found at field rates of 1.10 mM (Sholb.erg et al. 2001). Due to relatively high disease suppression rates, soluble coppers fit well in an integrated non-antibiotic program following early bloom Blossom Protect plus Buffer applications (Johnson et al. 2022).

Bacillus Products

Serenade Opti is considered a ‘fruit safe’ material, made by fermenting a strain of Bacillus subtilis. The antimicrobial activity of Serenade comes primarily from biochemical compounds produced by the bacterium during fermentation. Bacillus subtilis strain QST 713 (Serenade) has provided an average of 60% control in Oregon and is best used as part of an integrated program (Smith 2012, Johnson and Temple 2013b, Smith 2015). In 4 Washington trials from 2014 to 2022 Serenade Opti/Aso provided 50% median relative control (DuPont et al. 2023).

Oxidizing Agents

Several peracetic acid-peroxide products are available (e.g., Jet Ag, Oxidate 5.0) for fire blight. These low residue oxidative agents have the potential to damage microbial structures, such as membrane layers, and disrupt microbial cellular processes, like DNA or protein synthesis, leading to cell death (Wagner et al. 2002, Finnegan et al. 2010). Oxidizing agents (Jet Ag and Oxidate 5.0) produced median relative disease suppression of 53% and 62% in Washington with two to three applications post inoculation (4 trials: 2019-2022). When multiple post petal fall applications were made under slow drying conditions fruit marking occurred. In order to limit fruit marking potential peracetic acid-peroxide products should be applied only in fast drying conditions and up until the early post-petal fall period.

Plant Extracts

Plant essential oils of thyme and cinnamon have antibacterial activity against E. amylovora (Chizzola et al. 2008, Kokoskova et al. 2011, Tawfik and Shahin 2011, Akhlaghi et al. 2020). In Washington trials essential oil products Cinnerate, Thyme Guard and Thymox provided a median of 45% to 49% relative disease suppression comparable to recent trials in other states (DeShields and DeShields 2020, DuPont et al. 2023).

Other Biologicals

Bacteriophages are viruses that kill bacteria (Meile et al. 2017). Bacteriophage are an attractive option for integrated disease management due to their target specificity, however sensitivity to environmental conditions have thus far made application challenging (Gill and Abedon 2003, Nagy et al. 2012, Nagy et al. 2015). In Washington trials relative disease suppresison of bacteriophage products against E. amylovora has been variable with control below 20% observed in 2019 and 2020, while in 2022 three applications provided 58% relative disease suppression (DuPont 2023). This variability has also been seen in other regions. For example providing 35% and 39% relative suppression in Michigan 2019 trials and 74% and 42% in 2018 trials (Sundin et al. 2018, Outwater et al. 2019).

Systemic Acquired Resistance Products

Acibenzolar-S-methyl (Actigard 50 WG), is a synthetic inducer of systemic acquired resistance (SAR). Its mode of action is to mimic the plant hormone, salicylic acid, which is responsible for priming the plant’s defense system. The level of protection is smaller compared to an antibiotic but it lasts longer, approximately a week (Maxson-Stein et al. 2002). Actigard (2 oz.) plus an antibiotic applied during bloom improved the efficacy of antibiotics an average of 5% to 6% per application in trials in Washington and Oregon (Johnson et al. 2016). Therapeutic applications of Actigard to a two-foot section of the scaffold where fire blight cankers were removed have reduced the size of canker expansion and the number of trees which died (Johnson and Temple 2016, Johnson and Temple 2017).

Apple Materials

Excerpt from the WSU Crop Protection Guide. For timings at which each pesticide can be used refer to the Crop Protection Guide.

d = dormant; dd= delayed dormant; pp= prepink/pink; b = bloom; pb = post bloom; sf = shuck fall; es = early summer (14-32 after full bloom); s = summer; ls = late summer; ph = preharvest; h = harvest; ah = after harvest

Pear Materials

Excerpt from the WSU Crop Protection Guide. For timings at which each pesticide can be used refer to the Crop Protection Guide.

d = dormant; dd= delayed dormant; pp= prepink/pink; b = bloom; pb = post bloom; sf = shuck fall; es = early summer (14-32 after full bloom); s = summer; ls = late summer; ph = preharvest; h = harvest; ah = after harvest

 

Additional Resources

Decision Aid System

Visit for the recent model projections of blossom blight risk at your site.

Crop Protection Guide 

Crop Protection Guide recommendations are updated on an annual basis.

Cutting Fire Blight Infections

News article May 2023.

Organic Fire Blight Management in Western US

eOrganic article.

Cougar Blight Model

Plan for Multiple Fire Blight Conditions, Be Agile

Example programs for high and low risk blocks. WSU Newsletter article, Updated March 2022.

Canker Management

Fire blight cankers left in the orchard are the source for new spring infections. WSU Newsletter article, February 2022.

Fire Blight Susceptibility of Apple Cultivars

Written by: Sarah Kostick, WSU Horticultural Doctoral Candidate. May 2019.

Tips for Using Blossom Protect

WSU Newsletter article April 10, 2017.

Product Efficacy Trials

WSU Fire Blight Product Efficacy 2016-2022 Report

DuPont Cox Peter Johnson Integrated Fire Blight Management Final Report (f)

WSU Fire Blight New Product Efficacy Trials 2020

Fire Blight Management New Products and Effective Rates Fresh Pear Final Report 2019

WSU Fire Blight New Product Efficacy 2019

Integrated Fire Blight Management WSTFRC YR2 Report

Integrated Fire Blight Management WSTFRC YR1 Report

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Use pesticides with care. Apply them only to plants, animals, or sites listed on the labels. When mixing and applying pesticides, follow all label precautions to protect yourself and others around you. It is a violation of the law to disregard label directions. If pesticides are spilled on skin or clothing, remove clothing and wash skin thoroughly. Store pesticides in their original containers and keep them out of the reach of children, pets, and livestock.

YOU ARE REQUIRED BY LAW TO FOLLOW THE LABEL. It is a legal document. Always read the label before using any pesticide. You, the grower, are responsible for safe pesticide use. Trade (brand) names are provided for your reference only. No discrimination is intended, and other pesticides with the same active ingredient may be suitable. No endorsement is implied.

Important! Some of the pesticides discussed in this presentation were tested under an experimental use permit granted by WSDA. Application of a pesticide to a crop or site that is not on the label is a violation of pesticide law and may subject the applicator to civil penalties up to $7,500. In addition, such an application may also result in illegal residues that could subject the crop to seizure or embargo action by WSDA and/or the U.S. Food and Drug Administration. It is your responsibility to check the label before using the product to ensure lawful use and obtain all necessary permits in advance.

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