Tag Archives: bud rot

Preventing Mold & Fungus in Cannabis with Data Analytics

By Leighton Wolffe
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Cannabis legalization has taken the United States by storm, with 33 states approved for medicinal cannabis use — 11 of which are also approved for recreational use for adults aged 21 and over. With new patients and consumers entering the market every day, it’s more important than ever for cannabis cultivators to establish more effective methods for mold and fungal prevention in their crops and to ensure consumer confidence in their brands.

Today, many cultivators address the risk of mold and fungus growth by testing crops for contaminants at the end stage of production. While this helps to catch some infected product before it reaches the market, this method is largely ineffective for mold and fungal prevention during the cultivation process. In fact, recent studies have shown an 80% failure rate in mold and fungal testing in Denver cannabis dispensaries. By relying on late-stage, pass/fail testing, cannabis entrepreneurs also expose themselves to increased risk of lost crops and profits.

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

However, emerging sensor technologies exist that can test plants during the grow process, significantly reducing the risks associated with cannabis cultivation while increasing the bottom line for commercial grow operations. By leveraging data from these monitoring sensors along with environmental automation systems that are integrated with data analytics platforms, cannabis professionals can take a proactive approach to achieve the ideal environmental conditions for their crops and prevent against mold and fungal infestation.

Common Causes for Bud Rot in Indoor Growing Systems 

Botrytis cinerea — commonly known as “bud rot” — is a pathogenic fungi species that creates a gray mold infection in cannabis plants. An air-borne contaminant, it is among the most prevalent diseases affecting marijuana crops today and can lead to significant damages, particularly when left untreated during post-harvest storage. Bud rot is one of the most difficult challenges cannabis entrepreneurs face: Once plants have been affected, only 2% can be expected to recover. This is because Botrytis cinerea can use multiple methods for attacking host plants, including using the plant’s natural defenses against it to continue infestation.

While difficult to contain, bud rot is very easy to spot. Plants affected with the fungus will begin yellowing, experience impaired growth, and develop gray fungus around its buds. Overall crop yield will be significantly reduced, leading to decreased profit for cannabis cultivators. The biggest contributing factors to a Botrytis cinerea infestation are as follows:

  • Humidity: Indoor grow facilities that maintain humidity levels in excess of 45% are breeding grounds for mold and fungus. These environments can become perfect conditions for mold and fungal growth.
  • Temperature: Bud rot typically thrives in environments where temperatures fall between 65- and 75-degrees Fahrenheit, which is why greenhouses and grow rooms are often the victim of such infestations.
  • Ventilation: Poor airflow is another contributing factor to Botrytis cinerea Without proper ventilation, excess moisture buildup will eventually result in mold and mildew growth.
  • Strain: Some marijuana strains are better equipped to fend off bud rot infection. In particular, sativa plants have a higher resistance to mold development than their C. indica and C. ruderalis cousins.

Controlling mold and fungal growth in commercial grow facilities is a top priority for cannabis cultivators. Not only detrimental to their profitability and crop yield, infected plants can pose serious health risks to consumers, especially for immunocompromised patients. Consuming cannabis products that have been compromised by bud rot or other mold and fungal infections can cause a wide range of medical concerns, including pneumonitis, bronchitis, and other pulmonary diseases. As a result, growers are required to dispose of all infected plants without the possibility to sell.

Bud rot isn’t the only culprit responsible for cannabis plant destruction. Powdery mildew, Fusarium, sooty molds, and Pythium all contribute to the challenges faced by cannabis professionals. In fact, a recent study conducted by Steep Hill Labs and University of California, Davis – Medical Center found that in 20 randomly-selected samples submitted for testing, all samples showed detectable levels of microbial contamination7. Many of these samples also contained significant pathogenic microorganism contamination. Without proper detection and prevention methods in place, these pesky plant-killers will only continue to terrorize the cannabis cultivation industry.

The Current Cannabis Cultivation Landscape 

The data is clear: Current practices for cannabis cultivation are insufficient for preventing against mold and fungal growth. Sterilization and pass/fail testing do not identify the root cause of harmful infestations in plants, therefore leaving cannabis professionals in the dark about how to better optimize their grow conditions for improved crop reliability and safety. In order to prevent against damages incurred from mold and fungal infestation, marijuana growers must be more diligent in their grow condition monitoring practices.

Many cannabis professionals rely on manual monitoring to identify environmental changes within their indoor grow facilities. While it’s important to collect data on your operation’s essential systems, doing so without the right tools can be time-consuming and ineffective. Manual monitoring often relies on past data and does not illustrate the relationship between different systems and their impact on environmental changes. The goal is to assemble data from all the grow systems and create correlations on actual bio-environmental conditions during the grow process to compare to yield results. This is only available when an information management platform is synthesizing data from all the systems within the grow facility and presenting meaningful information to the growers, facility operators and owners.

Especially as the cannabis industry is expected to grow exponentially in coming years, growers need more robust tools for tracking and manipulating environmental changes within their indoor growing systems.

Leveraging Building Automation Systems & Data Analytics in Cannabis Cultivation 

A powerful approach to prevent environmental conditions that are known to lead to mold and fungus growth exists in leveraging the data produced from your grow facility’s various automation systems. Most commercial cultivation facilities have multiple stand-alone and proprietary systems to control their indoor environment, making it difficult to not only collect all of this valuable data, but also to achieve the level of grow condition monitoring necessary for mold and fungal prevention.

With some data analytics platforms, such as GrowFit Analytics, data is collected across disparate systems that don’t normally communicate with one another, providing access to the key insights necessary for achieving environmental perfection with your cannabis crops. A viable solution collects vital grow facility system data and relevant bio-environmental monitoring data, and delivers this information in one, centralized software interface. The software then will apply analytic algorithms to develop key performance indicators (KPIs) while working to detect system anomalies, faults, and environmental fluctuations. The right analytics solution should also be customizable, allowing you to track the KPIs that are most important to your unique facility, and to achieve the vision of your chief grower. Ultimately, the software should serve up actionable insights that empower facility management and growers.

Sample data visualization dashboard from GrowFit Analytics showing real-time Temperature and Relative Humidity readings and indicating potential Mold Risk as defined by the Grower.

Collecting reliable data from different grow facility systems and environmental sensors can be a complex process and the information collected illustrates more than just what’s working right and what isn’t. By implementing an advanced data analytics solution, cannabis cultivation professionals can now be empowered to track minute details about their indoor grow facility, providing a safer, healthier environment for their crops and avoiding those environmental conditions that lead to mold and fungus altogether.

An ideal data analytics platform won’t simply collect data to be analyzed at a later date, and simple trending of sensor data is not enough. Information — especially in a commercial grow facility — is time-sensitive, which is why growers should select a system that offers real-time analytics capabilities. Some platforms offering real-time analytics utilize cloud computing, allowing for easy access from anywhere while also providing enhanced security to protect sensitive facility data. The most robust data analytics platforms provide detailed historical data for your entire crop’s lifecycle that provide a “digital recipe” to replicate successful crops, and fine-tune the process for continuous improvement.

Data analytics tools can also impact the bottom line by lowering operational costs. GrowFit Analytics, for example, was born out of a software solution designed to lower energy costs for large complex buildings like commercial grow facilities.

The data and insights provided can help identify opportunities for greater energy efficiency, which can lead to significant utility savings. Grow facilities operate 24 hours/day, with energy expenses representing one of the largest operational costs. With data analytics tools at their disposal, facility managers are armed with the information they need to improve system efficiency, increase energy savings, and improve profitability.

Eliminating Mold & Fungus from the Future of Cannabis Cultivation 

By focusing on grow condition monitoring using data analytics tools, cannabis professionals can effectively eliminate the risk of mold and fungus growth in their crops. Leading data analytics tools make tracking environmental changes simple and easy to manage, allowing cannabis professionals to take a proactive approach to mold and fungus prevention. As we look to the future of the cannabis cultivation industry, it’s paramount for professionals to explore the technological advancements available that can help them address their business’ most pressing challenges.

The Best Way to Remediate Moldy Cannabis is No Remediation at All

By Ingo Mueller
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Consumers are largely unaware that most commercial cannabis grown today undergoes some form of decontamination to treat the industry’s growing problem of mold, yeast and other microbial pathogens. As more cannabis brands fail regulatory testing for contaminants, businesses are increasingly turning to radiation, ozone gas, hydrogen peroxide or other damaging remediation methods to ensure compliance and avoid product recalls. It has made cannabis cultivation and extraction more challenging and more expensive than ever, not to mention inflaming the industry’s ongoing supply problem.

The problem is only going to get worse as states like Nevada and California are beginning to implement more regulations including even tougher microbial contamination limits. The technological and economic burdens are becoming too much for some cultivators, driving some of them out of business. It’s also putting an even greater strain on them to meet product demand.

It’s critical that the industry establishes new product standards to reassure consumers that the cannabis products they buy are safe. But it is even more critical that the industry look beyond traditional agricultural remediation methods to solve the microbial problems.

Compounding Risks

Mold and other microbial pathogens are found everywhere in the environment, including the air, food and water that people consume. While there is no consensus yet on the health consequences of consuming these contaminants through cannabis, risks are certainly emerging. According to a 2015 study by the Cannabis Safety Institutei, molds are generally harmless in the environment, but some may present a health threat when inhaled, particularly to immunocompromised individuals. Mycotoxins resulting from molds such as Aspergillus can cause illnesses such as allergic bronchopulmonary aspergillosis. Even when killed with treatment, the dead pathogens could trigger allergies or asthma.

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

There is an abundance of pathogens that can affect cannabis cultivation, but the most common types are Botrytis (bud rot, sometimes called gray mold) and Powdery Mildew. They are also among the most devastating blights to cannabis crops. Numerous chemical controls are available to help prevent or stem an outbreak, ranging from fungicides and horticultural oils to bicarbonates and biological controls. While these controls may save an otherwise doomed crop, they introduce their own potential health risks through the overexposure and consumption of chemical residues.

The issue is further compounded by the fact that the states in which cannabis is legal can’t agree on which microbial pathogens to test for, nor how to test. Colorado, for instance, requires only three pathogen tests (for salmonella, E. coli, and mycotoxins from mold), while Massachusetts has exceedingly strict testing regulations for clean products. Massachusetts-based testing lab, ProVerde Laboratories, reports that approximately 30% of the cannabis flowers it tests have some kind of mold or yeast contamination.

If a cannabis product fails required microbial testing and can’t be remedied in a compliant way, the grower will inevitably experience a severe – and potentially crippling – financial hit to a lost crop. Willow Industries, a microbial remediation company, says that cannabis microbial contamination is projected to be a $3 billion problem by 2020ii.

Remediation Falls Short
With the financial stakes so high, the cannabis industry has taken cues from the food industry and adopted a variety of ways to remediate cannabis harvests contaminated with pathogens. Ketch DeGabrielle of Qloris Consulting spent two years studying cannabis microbial remediation methods and summarized their pros and consiii.

He found that some common sterilization approaches like autoclaves, steam and dry heat are impractical for cannabis due the decarboxylation and harsh damage they inflict on the product. Some growers spray or immerse cannabis flowers in hydrogen peroxide, but the resulting moisture can actually cause more spores to germinate, while the chemical reduces the terpene content in the flowers.

Powdery mildew starts with white/grey spots seen on the upper leaves surface

The more favored, technologically advanced remediation approaches include ozone or similar gas treatment, which is relatively inexpensive and treats the entire plant. However, it’s difficult to gas products on a large scale, and gas results in terpene loss. Microwaves can kill pathogens effectively through cellular rupture, but can burn the product. Ionizing radiation kills microbial life by destroying their DNA, but the process can create carcinogenic chemical compounds and harmful free radicals. Radio frequency (which DeGabrielle considers the best method) effectively kills yeast and mold by oscillating the water in them, but it can result in moisture and terpene loss.

The bottom line: no remediation method is perfect. Prevention of microbial contamination is a better approach. But all three conventional approaches to cannabis cultivation – outdoors, greenhouses and indoor grow operations – make it extremely difficult to control contamination. Mold spores can easily gain a foothold both indoors and out through air, water, food and human contact, quickly spreading into an epidemic.

The industry needs to establish new quality standards for product purity and employ new growing practices to meet them. Advanced technologies can help create near perfect growing ecosystems and microclimates for growing cannabis free of mold contamination. Internet of Things sensors combined with AI-driven robotics and automation can dramatically reduce human intervention in the growing process, along with human-induced contamination. Natural sunlight supplemented with new lighting technologies that provide near full-light and UV spectrum can stimulate robust growth more resistant to disease. Computational fluid dynamic models can help growers achieve optimal temperature, humidity, velocity, filtration and sanitation of air flow. And tissue culture micropropagation of plant stock can eliminate virus and pathogen threats, to name just a few of the latest innovations.

Growing legal cannabis today is a risky business that can cost growers millions of dollars if pathogens contaminate a crop. Remediation methods to remove microbial contamination may work to varying degrees, but they introduce another set of problems that can impact consumer health and comprise product quality.


References

i. Holmes M, Vyas JM, Steinbach W, McPartland J. 2015. Microbiological Safety Testing of Cannabis. Cannabis Safety Institute. http://cannabissafetyinstitute.org/wp-content/uploads/2015/06/Microbiological-Safety-Testing-of-Cannabis.pdf

ii. Jill Ellsworth, June 2019, Eliminating Microbials in Marijuana, Willow Industries, https://willowindustries.com/eliminating-microbials-in-marijuana/#

iii. Ketch DeGabrielle, April 2018, Largest U.S. Cannabis Farm Shares Two Years of Mold Remediation Research, Analytical Cannabis, https://www.analyticalcannabis.com/articles/largest-us-cannabis-farm-shares-two-years-of-mold-remediation-research-299842

 

Fungal Monitoring: An Upstream Approach to Testing Requirements

By Bernie Lorenz, PhD
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Mold is ubiquitous in nature and can be found everywhere.1 Cannabis growers know this all too well – the cannabis plant, by nature, is an extremely mold-susceptible crop, and growers battle it constantly.

Of course, managing mold doesn’t mean eradicating mold entirely – that’s impossible. Instead, cultivation professionals must work to minimize the amount of mold to the point where plants can thrive, and finished products are safe for consumption.

Let’s begin with that end in mind – a healthy plant, grown, cured and packaged for sale. In a growing number of states, there’s a hurdle to clear before the product can be sold to consumers – state-mandated testing.

So how do you ensure that the product clears the testing process within guidelines for mold? And what tools can be employed in biological warfare?

Mold: At Home in Cannabis Plants

It helps to first understand how the cannabis plant becomes an optimal environment.

The cannabis flower was designed to capture pollen floating in the air or brought by a pollinating insect.

Photo credit: Steep Hill- a petri dish of mold growth from tested cannabis

Once a mold spore has landed in a flower, the spore will begin to grow. The flower will continue to grow as well, and eventually, encapsulate the mold. Once the mold is growing in the middle of the flower, there is no way to get rid of it without damaging the flower.

A Name with Many Varieties

The types of spores found in or around a plant can make or break whether mold will end with bad product.

Aspergillus for example, is a mold that can produce mycotoxins, which are toxic to humans2. For this reason, California has mandatory testing3for certain aspergillus molds.

Another example, Basidiospores, are found outside, in the air. These are spores released from mushrooms and have no adverse effects on cannabis or a cannabis cultivation facility.

Fungi like powdery mildew and botrytis (PM and Bud Rot) typically release spores in the air before they are physically noticed on plants. Mold spores like these can survive from one harvest to the next – they can be suspended in the air for hours and be viable for years.

How Mold Travels

Different types of spores – the reproductive parts of mold – get released from different types of mold. Similar to plants and animals, mold reproduces when resources are deemed sufficient.

The opposite is also true that if the mold is under enough stress, such as a depleting nutrient source, it can be forced into reproduction to save itself.4

In the end, mold spores are released naturally into the air for many reasons, including physical manipulation of a plant, which, of course, is an unavoidable task in a cultivation facility.5

Trimming Areas: A Grow’s Highest Risk for Mold

Because of the almost-constant physical manipulation of plants that happen inside its walls, a grow’s trimming areas typically have the highest spore counts. Even the cleanest of plants will release spores during trimming.

Best practices include quality control protocols while trimming

These rooms also have the highest risk for cross contamination, since frequently, growers dry flower in the same room as they trim. Plus, because trimming can be labor intensive, with a large number of people entering and leaving the space regularly, spores are brought in and pushed out and into another space.

The Battle Against Mold

The prevalence and ubiquitous nature of mold in a cannabis facility means that the fight against it must be smart, and it must be thorough.

By incorporating an upstream approach to facility biosecurity, cultivators can protect themselves against testing failures and profit losses.

Biosecurity must be all encompassing, including everything from standard operating procedures and proper environmental controls, to fresh air exchange and surface sanitation/disinfection.

One of the most effective tactics in an upstream biosecurity effort is fungal monitoring.

Ways to Monitor Mold

Determining the load or amount of mold that is in a facility is and always will be common practice. This occurs in a few ways.

Post-harvest testing is in place to ensure the safety of consumers, but during the growing process, is typically done using “scouting reports.” A scouting report is a human report: when personnel physically inspect all or a portion of the crop. A human report, unfortunately, can lead to human error, and this often doesn’t give a robust view of the facility mold picture.

Another tool is agar plates. These petri dishes can be opened and set in areas suspected to have mold. Air moves past the plate and the mold spores that are viable land on the dishes. However, this process is time intensive, and still doesn’t give a complete picture.

Alternatively, growers can use spore traps to monitor for mold.

Spore traps draw a known volume of air through a cassette.The inside of the cassette is designed to force the air toward a sticky surface, which is capable of capturing spores and other materials. The cassette is sent to a laboratory for analysis, where they will physically count and identify what was captured using a microscope.

Spore trap results can show the entire picture of a facility’s mold concerns. This tool is also fast, able to be read on your own or sent to a third party for quick and unbiased review. The information yielded is a useful indicator for mold load and which types are prevalent in the facility.

Spore Trap Results: A Story Told

What’s going on inside of a facility has a direct correlation to what’s happening outside, since facility air comes infromthe outside. Thus, spore traps are most effective when you compare a trap inside with one set outside.

When comparing the two, you can see what the plants are doing, view propagating mold, and understand which of the spore types are only found inside.

Similar to its use in homes and businesses for human health purposes, monitoring can indicate the location of mold growth in a particular area within a facility.

These counts can be used to determine the efficacy of cleaning and disinfecting a space, or to find water leaks or areas that are consistently wet (mold will grow quickly and produce spores in these areas).

Using Spore Traps to See Seasonality Changes, Learn CCPs

Utilizing spore traps for regular, facility-wide mold monitoring is advantageous for many reasons.

One example: Traps can help determine critical control points (CCP) for mold.

What does this look like? If the spore count is two times higher than usual, mitigating action needs to take place. Integrated Pest Management (IPM) strategies like cleaning and disinfecting the space, or spraying a fungicide, are needed to bring the spore count down to its baseline.

For example, most facilities will see a spike in spore counts during the times of initial flower production/formation (weeks two to three of the flower cycle).

Seasonal trends can be determined, as well, since summer heat and rain will increase the mold load while winter cold may minimize it.

Using Fungal Monitoring in an IPM Strategy

Fungal monitoring – especially using a spore trap – is a critical upstream step in a successful IPM strategy. But it’s not the only step. In fact, there are five:

  • Identify/Monitor… Using a spore trap.
  • Evaluate…Spore trap results will indicate if an action is needed. Elevated spore counts will be the action threshold, but it can also depend on the type of spores found.
  • Prevention…Avoiding mold on plants using quality disinfection protocols as often as possible.
  • Action…What will be done to remedy the presence of mold? Examples include adding disinfection protocols, applying a fungicide, increasing air exchanges, and adding a HEPA filter.
  • Monitor…Constant monitoring is key. More eyes monitoring is better, and will help find Critical Control Points.

Each step must be followed to succeed in the battle against mold.

Of course, in the battle, there may be losses. If you experience a failed mandatory product testing result, use the data from the failure to fix your facility and improve for the future.

The data can be used to determine efficacy of standard operating procedures, action thresholds, and other appropriate actions. Plus, you can add a spore trap analysis for pre- and post- disinfection protocols, showing whether the space was really cleaned and disinfected after application. This will also tell you whether your products are working.

Leveraging all of the tools available will ensure a safe, clean cannabis product for consumers.


References

  1. ASTM D8219-2019: Standard Guide for Cleaning and Disinfection at a Cannabis Cultivation Center (B. Lorenz): http://www.astm.org/cgi-bin/resolver.cgi?D8219-19
  2. Mycotoxin, Aspergillus: https://www.who.int/news-room/fact-sheets/detail/mycotoxins
  3. State of California Cannabis Regulations: https://cannabis.ca.gov/cannabis-regulations/
  4. Asexual Sporulation in Aspergillus nidulans (Thomas H. Adams,* Jenny K. Wieser, and Jae-Hyuk Yu):  https://pdfs.semanticscholar.org/7eb1/05e73d77ef251f44a2ae91d0595e85c3445e.pdf?_ga=2.38699363.1960083875.1568395121-721294556.1562683339
  5. ASTM standard “Assessment of fungal growth in buildings” Miller, J. D., et al., “Air Sampling Results in Relation to Extent of Fungal Colonization of Building Materials in Some Water Damaged Buildings,” Indoor Air, Vol 10, 2000, pp. 146–151.
  6. Zefon Air O Cell Cassettes: https://www.zefon.com/iaq-sampling-cassettes