An end of year reflection from NBS

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A new breeding line, selected from the greenhouse May 2017 for uniformity, cannabinoid content, aroma, and flower quality. 

 'Cloud Nine' a new hybrid being tested at NBS October 2017 using the line selected above - I'm convinced it will surpass most autoflowers on the market today for quality and uniformity. 

'Cloud Nine' a new hybrid being tested at NBS October 2017 using the line selected above - I'm convinced it will surpass most autoflowers on the market today for quality and uniformity. 

 Outdoor trials 2017. Excellent growth despite a historically bad spring. It is wonderful to be able to welcome growers to visit us in an transparent industry. 

Outdoor trials 2017. Excellent growth despite a historically bad spring. It is wonderful to be able to welcome growers to visit us in an transparent industry. 

 Greenhouse 2 in construction, December 2017. We had intended to build this last year, but a little thing called 'money' got in the way. Looking forward to inreasing the breeding output in 2018. 

Greenhouse 2 in construction, December 2017. We had intended to build this last year, but a little thing called 'money' got in the way. Looking forward to inreasing the breeding output in 2018. 

December is a relatively quiet time for us and a good time to reflect on the state of the industry and our goals. There are a lot of good people out there in the industry doing good work in the face of strong headwinds. Problems like...

  • Pollen from 'hemp' crops threatening production (see last post).
  • Banking and tax restrictions that make business difficult at best, unsustainable at worst.
  • The dire need for research into pest control, post-harvest handling and the health and social impacts of cannabis use.
  • The impact of the 'green rush' on a very limited market - there are over 800 licensed producers in Oregon today, and more applications waiting. I believe there is a real risk of an disastrous overproduction that is going to make the business difficult or impossible for many growers. 
  • An unstable federal situation that puts the whole industry on edge, and possibly at risk. 

I spend more time than I should worrying about all of these issues (and many others). The only relief I've found is in trust (that is to say, faith in action). Horticulture and plant breeding has taught me a lot about trust. Every time I put a seed in the soil I must have trust that it will grow. Every time I put a plant outside is an act of trust in the seasons. Every selection I make is an act of trust informed by analysis. We interact with our business partners with trust, and hope they will do the same. Without trust, I would be not be able to act. And without action, I am not going anywhere...       

Many of us in the industry are 'all in' to create a healthy and well regulated industry - one that provides good jobs and tax dollars for education, produces a quality, clean product and keeps money out of the hands of criminal organizations. For us, there is no choice but to trust, and know that even if it does not work out, there is value in having taken the high road. 

Wishing a a happy and prosperous 2018 to all! 

 

The Pollen Problem

Cannabis is an unusual crop due to the fact that the most valuable part is an un-pollinated flower. In most other crops the harvested portion is either non-reproductive (like spinach) or pollination is necessary for either production of fruit (like squash) or seed (like sweet corn). The only other crop I can think of whose quality is destroyed by pollination is pineapple. The pineapple is native to South America; but the production is done in places like Hawaii because there are no natural pollinators (hummingbirds!) in Hawaii. In fact, state law prohibits hummingbirds on Hawaii as they would potentially ruin the pineapple industry.  

Unfortunately, cannabis pollen is tiny (~20 micrometers) and is carried by the wind, not hummingbirds. This creates a problem for high value THC/CBD cannabis flower producers when they are growing in proximity to hemp fields. Seed and fiber hemp fields either typically have a significant percentage of male plants or are monoecious ('hermaphroditic'). Even CBD-oil "hemp" fields often have some male or monoecious plants in them due to their large size and lower intensity of management. 

In the seed industry, cross-pollination problems are usually solved collectively though the voluntary use of a 'pinning map'. Seed growers in a given region will mark their fields on the map, and ensure that no fields that might contaminate their seed crop are within an agreed upon radius (which depends on the crop). Again, unfortunately for cannabis, we do not even know what distance is required to isolate sinsemilla crops from hemp fields. The distance required between two hemp seed fields is established - but is for a case where the pollen produced in one field will compete with the pollen produced from the neighboring field. No one really knows how far away a pollen producing field has to be from a field with no pollen in order to minimize seeding. And what level of seeding is acceptable for a sinsemilla producer? 

Given the explosion in the number of acres planted to 'hemp' in Oregon, I expect we're going to hear a lot about sinsemilla crops that lost a lot of value due to neighboring pollen. In fact, our own fall quality control trials were heavily seeded. As a result, we're facing a possibly intense battle between the high-value, small-scale sinsemilla producers and the larger hemp producers. In my opinion, in order to protect the developing industry in Oregon, there should be a requirement that fields are carefully inspected and any pollen producing plants removed (we'd be out of business though, if there was not with the exception for males used for breeding and stock seed production). 

Intercropping results at Oregon Blissful Botanicals

This week I went to visit Eric with Oregon Blissful Botanicals in Damascus. Eric sowed a few thousand of our seeds in late April, transplanted outside in mid-May, and is in the process of harvesting as I write (mid July).

 Eric with County Fair plant

Eric with County Fair plant

Despite a unusually cold and rainy May, Eric managed to grow some of the largest day neutral plants I've ever seen - many reaching head height! He attributes this to his deep, heavily amended beds, which give plenty of soil volume for the plant roots to explore, as well as personalized attention to the plants - hand feeding forces the growers to pay constant attention to each plant's health. Eric also uses extensive cover cropping around the base of his beds. 

While yields overall are going to be very good from the autoflower crop; uniformity is far less than ideal with variation in morphology from plant to plant pretty high - this makes nutrient and harvest management more difficult. This is a classic case of gene x environment (GxE) interaction - when we grow these varieties in the greenhouse they often mature at the same time and size, but when they are exposed to cold weather the genes express themselves differently and we see much more variation from plant to plant. 

Eric chose to plant his autoflower plants using an intercropping model, in which day neutral plants are planted early, then photoperiod plants come in later and replace the space where the autoflowers were growing. Eric is hoping to get a full sized harvest off of his photoperiod plants, plus an additional partial harvest from the day neutral, thereby making optimal use of his OLCC canopy.  Thank you Eric for working with us this season, and best of luck with all your harvests!

Mature day neutral plants flank the space where photoperiod plants are growing. 

July 7 Update and Florida Weave

A brief update on what is happening on our farm right now, and some instructions on how to tie up plants in pots so they don't fall over in the wind using a technique from tomatoes called the 'Florida weave'. Somehow the end of the video got cut off - I was just going to say that if you tie low on the plant you minimize the risk of damaging side shoots... Happy Growing!

Limits to growth...

All plants need a number of inputs to grow well: light, water, nutrients, carbon dioxide; as well as an appropriate environment (temperature, humidity) in which to grow. 

Different plant species naturally vary in their requirements for each of these - lettuce can grow well under relatively low light conditions and cooler temperatures than say, peppers. In terms of temperature and light requirement, cannabis is more like pepper than it is like lettuce.

Cannabis will survive temperatures in the 30s at night, but this puts a lot of stress on the plant and they will not grow well. Even temperatures in the mid 40s are not ideal - like pepper and tomato, in our experience cannabis really needs nighttime lows of 50+ to thrive. This is the limiting factor for growth in the climate in Oregon, as nighttime lows are only reliably in the 50s from June-August. The use of greenhouses dramatically extends the season for optimal growth in our climate. The plants grow optimally with daytime temperatures of 75-85F; temperatures above 90 start to cause stress and will slow growth. 

A lot of people overestimate the need for light - the fact is that there is plenty of light to grow high quality plants at least from March-October in Oregon. What limits growth during this time is outdoor temperatures. At the same time, in a warm indoor or greenhouse space, carbon dioxide can become limiting. By adding carbon dioxide we can force plants to grow faster - but only if the temperatures and light levels match the carbon dioxide requirement! 

It is a complicated relationship between each of the inputs, the plant, and the environment - if any one piece is missing the plant will not perform as well as it could otherwise, and any time you change one variable you potentially alter how the plant will react to the others! 

Becoming a better grower requires a time commitment - it is important to spend time with your plants, observe them, ask yourself what is limiting their growth, and experiment!

Questions on yields

One of the most frequent questions we get about our autoflowering (day neutral) varieties is what yields a grower can expect. Yields can vary a lot depending on growing conditions - day and night time temperatures, plant density, nutrient availability, and light. The results from a spring sowing outdoors will not be the same as those in the main season. Hoop houses will perform differently from climate controlled greenhouses. The best we can do is report results coming from our actual growers. 

Yesterday one of our first OLCC growers called us and reported 4 to 5.5oz yields per plant from Amnesia and Timberline indoors. He was quite happy with the low level of labor involved with these plants - no cuttings, no change in lighting, minimal pruning or trellising - Not bad for a 90 day plant! He also sent over some photos:

 

 

 

 

 

A story of two plants

First, a disclaimer: I am not a medical professional and the opinions I am about to express should be considered as personal opinions, and in no way construed as medical advice.

The opium poppy (Papaver somniferum) and Cannabis sativa have a lot of things in common. 

  • Both have been cultivated by humans for thousands of years
  • Both have been used medicinally over the same time span
  • Both have had ridiculous laws enacted to restrict their cultivation
    • It is illegal to grow opium poppies in the USA - but confusingly legal to grow the exact same plants for culinary or ornamental purposes. The only difference between the two is whether you are aware that ornamental somniferum poppies = opium poppies
    • I assume you already know the ridiculous laws regarding cannabis... 
  • Neither are as dangerous as any number of common garden plants, such as Oleander (a single leaf can kill a small child) or Foxglove. 
  • Both are used to manage pain
  • Both have the potential for abuse

Now let's contrast the two plants

  • The investigation and utilization of morphine and other opioids derived from the poppy plant represent one of the greatest, if not the greatest medical advance in history. Opioid drugs take a place at the side of other great discoveries, such as antibiotics, vaccines and germ theory. The ability to manage pain is fundamental to quality of life. At the same time, opioid drugs come with significant risks and side effects. Constipation, physical dependence, nausea, and overdose are some of the substantial risks of opioid treatment. 
  • Cannabis, on the other hand, is virtually unstudied by modern medicine. There is strong anecdotal evidence that it is therapeutic for a number of indications, including chronic pain. The side effects are also understudied in an scientific context - but one thing is clear - overdose is impossible

Given epidemic of opioid overdoses in this country, I would suggest that any reasonable person would think that the investigation of the potential of cannabis in the treatment of chronic pain is not only justified, but that not doing so is a disservice to people suffering from pain everywhere. 

 

 

Day-neutral (autoflowering) cannabis - an evolutionary story

Imagine cannabis growing in the wild in Central Asia.  A seed is carried, perhaps by bird or by flood, to a riverside site where the seed germinates and start to grow. Cannabis is a ruderal (or pioneer) species - it moves into a disturbed area, grows very quickly and reproduces prolifically. To put it another way, the strategy of a ruderal plant is to 'get while the getting is good'. In order to take full advantage of the site and the season, a cannabis plant will grow as large as possible in the vegetative state before reproducing. To help with this, most cannabis a mechanism to sense the seasons - something called photoperiodism.  By sensing the length of the day (or, actually, the night), cannabis plants 'know' that the days are shortening and that winter is coming. This triggers them to begin to flower and produce seeds, and the cycle continues....

Except when it doesn't. Imagine that our cannabis plant has been successful and produced a large quantity of seed. This seed is dispersed - birds pick up a number of seeds and carry them north, into the Russian steppe and beyond. These seeds find a favorable spot to germinate, grow to be large plants with the long days of summer, and then, just as they are starting to flower, a heavy frost comes and kills them all stone dead. No seeds. The plant has been betrayed by the photoperiod response, which convinced the plants that they should keep growing when when, in fact, there was no longer enough time for to reproduce.

This probably happened a lot. Millions of cannabis plants behaving like the grasshopper, when they should have been the ant. Eventually, that heavy selective pressure, combined with the process of mutation, resulted in a plant that no longer listened to its internal clock - and what is known as 'autoflowering' or day-neutral cannabis was born. 

This variant cannabis will grow for the minimum amount of time possible in a vegetative state, and then transition to flowering, regardless of day-length. This adaptation allows it to complete the life-cycle in very short season areas, but comes at the cost of the ability to grow to large size. This trait, developed in the wild, has also proved to be a useful in the breeding of cultivated cannabis. By moving the trait from the weedy 'ruderalis' plants into a drug-producing background, breeders develop varieties that can produce outdoors regardless of day length. This has multiple benefits for the home gardener and commercial grower. The short cycle allows for outdoor harvest during favorable periods - avoiding the wet weather that caused 50% crop loss to mold in the Willamette Valley in 2016.  The smaller plants are also easier to care for - they can be grown in a pot on a back porch, and do not require trellising and pruning which dramatically reduces labor inputs. The plants in the photo below are flowering in July. 

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What are feminized seeds?

Plants are more varied in the mode of reproduction than us mammals.

  • Some flowering plants have 'perfect' flowers, which contain both male and female parts. (Tomato is an example)
  • Some flowering plants are 'monoecious' - meaning they have male and female flowers on the same plant, but in different places (Corn is an example - the tassel at the top is male, the ear is female)
  • Some flowering plants are 'dioecious' - meaning they have male flowers on one plant, and female flowers on another (Spinach is an example)
  • Some plants can also reproduce asexually, from cuttings, tubers, or rhizomes. 
  • Some plants can express multiple modes of reproduction - cannabis is one of these! 

Depending on the genetic background, cannabis can be monoecious or dioecious, and can also be propagated by cuttings (clones).

For those unfamiliar with the reproductive organs of cannabis, here are a couple of photos of young male and female flowers. 

 The female flowers each have two pistils (white hairs) that receive the pollen, while the male flower, when it develops, will open up like an umbrella and shed pollen into the air, to be carried by the wind to the female. 

The female flowers each have two pistils (white hairs) that receive the pollen, while the male flower, when it develops, will open up like an umbrella and shed pollen into the air, to be carried by the wind to the female. 

The most interesting cannabis product in terms of THC/CBD production is the unpollinated female flower bud - sinsemilla (spanish for 'without seeds') - so people avoid growing male plants and monoecious plants, both of which would reduce the quality of the buds by fertilizing the female flowers and producing seeds.

Sex is (mostly) genetically controlled in cannabis, so if you pollinate a female with a male, just as with people, about half of the offspring will be male, and half female. This is fine for seed production, but a pain for cannabis growers using seeds, as half of the seeds will be both unproductive (no female flowers) and in fact will threaten their sinsemilla crop with pollen. 

Fortunately for cannabis producers, cannabis is also quite flexible in its sexual expression. If you alter the hormonal signalling in the plant, you can over-ride the 'normal' (genetically determined) sexual phenotype. In this way, a genetically female plant can be tricked into producing pollen. And when you pollinate a female plant with female-source pollen you get ..... 100% female offspring rather than 50% male. This is how feminized seed is produced. This trick has been used for some time in hybrid seed production of cucumber and other cucurbits. 

Why do the plants do this? One possible story: It is possible that this evolved as a mechanism for plants to reproduce in otherwise bad conditions. Imagine you are a genetically female cannabis plant, growing in a stressful place (not enough water or food, too much competition). It takes a lot of energy to produce seeds, and clearly the place the plant is growing is not an ideal place to have kids. So instead, the plant will produce pollen, which will be carried on the wind for miles, potentially contributing to the next generation, and maybe finding a more fertile place to grow.  

What this also means is that, whether they are growing regular or feminized seeds, cannabis producers need to be careful to monitor their crop and check for stressed-out plants that might be considering pollen-production as a back-up plan. 

The Summer is past

The last time I wrote a blog entry we were ramping up for the end of our first cycle in the greenhouse. Since then we have harvested our first crop, replanted, harvested an outdoor crop, processed seed and done quality control... I'm excited to say that we are close to ready to launch our product for Oregon home and commercial growers.  Below are some photos showing some of the progress this summer... 

 A block of plants we recently harvested - grown out as a model of commercial production. 

A block of plants we recently harvested - grown out as a model of commercial production. 

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 A cola from a variety harvested in our greenhouse during our first cycle

A cola from a variety harvested in our greenhouse during our first cycle

 Clean seed, ready for packaging!

Clean seed, ready for packaging!

Healthy seeds, healthy plants

Often, when seeds fail to grow properly, home growers blame themselves. But some times, it is the fault of the seed producer. 

The photo on the left is of a young plant with a genetic defect in photosynthesis. The plant on the right is affected by genetic dwarfism linked to rugose (wrinkled) leaves. Neither of these will make a viable crop, no matter how good the grower is. In a lot of out-crossing crops, inbreeding will increase the frequency of these kinds of deleterious alleles - and they are all too common (up to 20%!) in some of the cannabis seed lots we have grown out. The acceptable rate for such off-types depends on the severity of the problem, and the crop in question - usually less than 0.5% would be considered acceptable (but not great).

We have also seen issues with germination in some seed lots. This is why, for crops other than cannabis, federal and state seed laws require seeds to be tested (and frequently labeled) for germination before sale. 

Healthy, fresh seeds require no special treatment to germinate successfully - cannabis seeds will emerge in 5 days even when planted 1"-2" into the soil, with good soil temperature and moisture. In our view, excessive manipulation of seeds (e.g. placing in damp paper towels to start germination) is not only unnecessary, it increases the risk of damaging the fragile sprouts during handling. 

Once you have purchased seeds, how do you keep them healthy? They should be stored in a cool, dry place - a pantry shelf or drawer is fine. If the seeds are dry and in an airtight container, you can increase their life by refrigeration, but do not store seeds where they will be exposed to high humidity. Seeds can also be kept for very long periods in a freezer, but moisture conditions must be carefully controlled, and defrost cycles avoided.

The future of cannabis in the US is being created by our actions today

As a plant breeder, a substantial part of my job is that of fortune-teller. Plant breeding is a long-term proposition, and the breeding targets I choose today won't bear fruit (so to speak) for years, or in some cases decades. So I ask myself: What will the production practices look like in 10 years? What traits will the consumer want? What diseases will become problematic? 

The flip side of this long-term perspective is that in some cases our choices today actually create the future.  By working towards a vision for the future, we are actually making a viable option for the future; one that would not exist without that vision and that labor. Of course we cannot defy the laws of nature, and it is always possible to be blindsided by an alternative that we had not considered (e.g. the rise and fall of any technology, such as fax machines). But like a sailing ship, as long as you don't sail straight into the wind, you can usually get to where you want to go. 

Taking that perspective, I want you ask yourself about the future of cannabis in the USA.

Will legalization proceed, if not at a federal level, then in a majority of states? The winds are in our favor, with 58% of Americans favoring legalization.   

What can stop us? Irresponsible use, criminal activity, violation of regulations. You know, as a new industry, we are under much higher scrutiny than say, alcohol. But remember: all of these problems are under our own control. We make the future. Encourage responsible use, and use responsibly yourself. Be a role model in our highly regulated industry, and some day the regulations will become unnecessary. 

What can help us? Creating jobs and putting the money to good use. Be a net benefit to the community, state, and country.

Consider sitting down for five minutes today to think about what you want the industry to look like in ten years. How are you going to make it happen, starting today? 

A retraction on the subject of patents

Going back to my post on April 18 regarding plant breeder's rights: I must issue a retraction regarding my comment that the USPTO would be unlikely to issue a patent for cannabis. Further research has brought to my attention that a utility patent has been granted on cannabis - #9095554. This patent was awarded August 4th 2015.  By my reading, the patent is attempting to protect a cultivars of cannabis that have at least 3% CBD, 'non-dominant' myrcene in the terpene profile, and greater than 1% terpenes overall. 

We are licensed!

I'm proud to report that the OLCC approved our application to produce cannabis today; we will start growing operations very shortly. While we won't have seeds ready for sale until the fall, please check back regularly for blog posts and updates on the growing season

Here's a photo from the OLCC of their first group of license holders.

A lack of crop rotation will threaten outdoor growers over the long term

Crop rotation has been considered a basic principle of sustainable agriculture for thousands of years. Rotation of the crop grown on a field (including a fallow period) benefits the grower and the environment by improving soil fertility and tilth, and controlling pests and weeds.

Legal outdoor cannabis growers are in a unique historical situation - they are required to grow their crop behind large fences, with costly security cameras and other infrastructure in place. The cost of complying with regulations severely limits the potential for crop rotation, with many growers planting in exactly the same location year after year. 

This is not the grower's fault, but we will undoubtedly observe a buildup of cannabis pests and disease over the coming years with the following consequences: 

  • growers more dependent on pesticides
  • diseases more resistant to those pesticides
  • threats to consumer health

Making matters worse is the need to dispose of unwanted plant material near the grow-site. Compost piles can create a reservoir for disease and insects to survive over the winter. I'd encourage all growers to be very careful about sanitation and hygiene, as well as the source of any plant material that may be brought onto the farm.  

Let's hope the march of progress in cannabis legalization proceeds. In the meantime we'll be working on breeding more disease resistant varieties. 

Plant breeder's rights and the future of cannabis

A lot of people are concerned about the patenting of crop species, including cannabis. Some question the ethical implications of patenting a living organism. Others are more pragmatically concerned about the effect of patents on biodiversity and the availability of genetics. Occasionally people express fear that big companies will patent all available cannabis varieties, leaving nothing for anybody to legally grow. In any case, IP protection in the plant genetics world is unquestionably complicated, and changing quickly.  I hope this post can help people understand the ways in which plant varieties are protected, the reasons behind it (good or bad). At the end I will speculate on the risks to cannabis biodiversity and where we are headed. 

In the USA today, plant varieties can gain legal protection via the following means:

  • Plant Patent (NOT the same as utility patent )
  • Plant Variety Protection (PVP)
  • Utility Patent
  • Licensing agreements (aka 'Bag tags')

Let's walk through these one by one. 

Plant patents are the oldest mechanism of protecting plant inventions, established 1930. Before 1930 there was no protection for plant inventions - a breeder could work years on a project only to have someone else take it, reproduce and sell it the following year. Plant patents were created in response to the work of Luther Burbank, a famous plant breeder (if there is such a thing) who lived from 1849-1926. If you're interested in his life, I'd recommend reading "The Garden of Invention" by Jane Smith. The feeling at the time was that by giving plant breeders control over their inventions for a defined amount of time (20 years) you would encourage further innovation. 

Plant patents only apply to asexually propagated crops, like many fruit and nut trees, and vines. Tubers, like potatoes, were exempted at the time because they are also used as food To be awarded a plant patent, the inventor must demonstrate the the variety meets the DUS criteria. In addition to being new, a cultivar must be:

  • (D)istinct from other varieties
  • (U)niform in its characteristics of distinction
  • (S)table from generation to generation 

Very similar to Plant Patents, Plant Variety Protection (est. 1970) applies to seed (and tuber) propagated crops, which includes most vegetable and field crops. PVP has the same criteria for protection as plant patents, just applies to different crops.

Interestingly, in many European countries the criteria are more stringent. Not only do you have to show that a variety is DUS, but you often also have to demonstrate that your variety is an improvement over the currently available varieties in order to get it entered onto the national variety list. Entry onto the national list mandatory for the commercial cultivation of certain crops. 

The PVP act expressly allows the use of PVP material for plant breeding purposes. It also allows farmers to save seed for their own use. Not so bad, right?  

Utility patents on plants are where things start to get less friendly. Court decisions in 1980 (Diamond v Chakrabarty) and 1985 (ex parte Hibberd) established that plant inventions were subject to protection by 'regular' patents (called utility patents to distinguish them from plant patents). In general, these patents are used to protect the method of creating a new variety, or the DNA sequences (e.g. the Roundup Ready construct) used to create a variety. Utility patents do not allow seed saving by farmers or use by breeders. 

More recently, utility patents have been extended to theoretically cover varieties created through traditional breeding, and not just the methods or genetic constructs used to create them. However, in order to gain protection any such varieties must be demonstrably novel, and "non-obvious". Whether something is 'obvious' or not is a very sticky matter. 

Licensing agreements aka 'Bag-tags' are kin to the software EULAs that no one ever reads - by opening the package the purchaser agrees to whatever terms the manufacturer has placed on the package. Personally, I hate to see these on bags of seed. To me, it doesn't seem fair to put whatever restrictions you like onto your product, regardless of legal protection by other means (like legitimate patents or PVP) and the nature of the product itself. Bag-tags are questionably enforceable, but seem to be often upheld in court. Licensing agreements are already employed by in cannabis. 

And now, a little perspective: 

As a plant breeder, I am in favor of plant patents and PVP. They provide incentive for breeders to invest years into breeding projects, while at the same time ensuring the genetics remain available for further progress. Utility patents and (more so) licence agreements make me nervous because they limit the ability of others to build upon genetic progress, and can limit the availability of genetics to growers.

That being said, I don't think utility patents are a huge threat to cannabis for the following reasons: 

1. The USTPO is unlikely to award patents for cannabis due to its current federal status. 

2. Patents expire! Licence agreements and biological protection mechanisms (perhaps the topic for another blog post) do not!

3.  To be patented, a cultivar has to be new and non-obvious. Both of these would be hard bars to meet for any currently available cultivars.  

4. Patents are expensive to obtain and defend. Typically agriculture companies only pursue and defend patents that provide them significant advantage over a long period - like a new disease resistance. There are many crops where patents and PVP are rare to nonexistent - often the breeding moves faster than the patenting process, making obtaining a patent for a run-of-the-mill variety uninteresting. Refer to the table below (from http://gmopundit.blogspot.com/2012/06/seed-biodiverity-as-measured-on-in.html). 

You will notice that 675/854 Utility patents filed to date are for field corn alone. This is because field corn seed is really big business. Monsanto sold 6 billion of dollars of seed corn (and traits) in 2015, and holds about 30% of the market. I've heard estimates that the retail market for cannabis in the USA is ~50 billion - but how big is the cannabis seed market? It will be bigger than most (possibly all) vegetables, but will be smaller than corn for a long time.  

While utility patents may not be a big threat, license agreements, unfortunately, may become common.  The good news is that these agreements won't restrict the availability of current genetics. 

As a final note, I'd suggest that the pharmaceutical industry as a larger threat to the future of cannabis biodiversity than the horticulture industry. Horticulture works at the plant level, and there is space in horticulture (and agriculture) a range of cultivation methods, grower needs, and consumer preferences. Pharmaceuticals, on the other hand, seek to reduce the plant to one or a few constituent parts. Cannabis-as-pharmaceutical would be, frankly, boring - concerned only with maximizing the extraction of active ingredient.