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Industrial hemp overview provided at Farm and Ranch Days

by Wyoming Livestock Roundup

Published on Feb. 22, 2020

During the Fremont County Farm and Ranch Days in Riverton Feb. 5 and 6, University of Wyoming (UW) Extension Educator Jeremiah Vardiman and UW Integrated Pest Management Specialist and Hemp Agronomist John Connett provided an overview of industrial hemp in the state of Wyoming.

Hemp vs. marijuana

            “The first thing I want to address is the misconception regarding hemp and marijuana,” stated Vardiman. “Some people say they are completely different species, while others say they are the exact same thing. Neither are quite right.”

            “Marijuana and hemp are in the same family, along with hops and hackberries,” Vardiman said. “Hops are the closest relative to hemp in terms of a plant species that is currently being cultivated.” 

            To help drive home the idea that hemp and marijuana are neither the exact same plant or completely different species, Vardiman uses dogs as an analogy. 

            “There are golden retrievers, boxers and labs. They are all different types of dogs, bred for different purposes,” he explained. “However, they are all the same species – they are all dogs, and they can all intermix freely. It is the same thing with hemp.” 

            With this in mind, Vardiman noted it doesn’t matter if a producer is breeding industrial hemp for seed, grain or CBD oil, or if they are growing marijuana, the crops can interbreed because they are the same species. 

            He also noted the main difference between industrial hemp and marijuana is the legal classification. 

            “Industrial hemp is anything containing 0.3 percent or less tetrahydrocannabinol (THC), which is the psychoactive element in marijuana that gives people a high,” Vardiman explained. “If it has 0.4 percent or greater, it is  classified as marijuana.” 

            Vardiman also noted a common misconception around industrial hemp is that THC and cannabidiol (CBD) are the same compound. 

            “THC and CBD are not the same thing. Don’t get the two confused,” he stated. 

Industrial hemp

            Vardiman explained industrial hemp is a herbaceous plant, meaning it contains low amounts of wood and has soft, green stems. He also noted it is not a perennial plant so producers have to replant year after year, depending on what they are planting it for.

            “Some industrial hemp species are also dioecious plants, meaning they have different male and female plants,” Vardiman explained. 

            He noted this becomes an issue because hemp is also wind pollinated.

            “Therefore, we are going to run into isolation issues when we are growing certain types of these products because when harvesting CBD oil, we harvest the female flowers and don’t want any fertilization of those plants,” he said. 

            He explained research in the Mediterranean found hemp pollen is able to move up to 10 miles away from the source plant.

            “This is a huge distance,” Vardiman stated. “And who knows what it will do in the Wyoming wind.” 


            “One of the biggest misnomers I am hearing from producers is that they are just going to use their least productive ground to grow hemp or carve out some new ground to grow it on,” said Vardiman. “However, we are going to want to treat hemp like a grain crop in the way it is grown and managed.” 

            He noted corn is most likely the closest to hemp in terms of fertilitiy, irrigation and management.

            “We don’t go out and throw corn in our worst ground. We want to grow it on our highest-quality ground and the same is true for hemp,” he stated.

            Vardiman pointed out Kentucky, Colorado and Washington have all legalized hemp, so they are trying to glean as much information from them as they can.

            “Research from these three states shows what they have found to be the most ideal conditions for growing industrial hemp,” said Vardiman. “They tell us well-drained soil is best, no heavy clays. The optimal pH is six to seven and it is sensitive to soil crusting and compaction, much like our grain crops.” 

            “Up in Powell, where I’m from, the soil pH is around eight or nine, but we don’t know if hemp will grow in those conditions because we don’t have any research that addresses this,” he noted. 

            Vardiman noted producers may be able to change their soil pH, although it is expensive and most likely un-economical. 

            “Producers can just add an acid to their field to bring the pH down, but it is only a temporary fix so they would have to do it annually or every other year. I’m just not sure it would be economical,” he stated. 

            Vardiman told producers if they don’t know the pH of their soil, he highly recommends sending it off for a soil analysis. The nearest labs are at Colorado State University or Ward Labratories in Nebraska.

            Another thing to note about industrial hemp, according to Vardiman, is that it is a photoperiod-sensitive plant, meaning it doesn’t develop or mature based on growing days or heat index.

            “Day length triggers the plant to mature and start flowering,” he explained. “Therefore, it doesn’t matter, to a degree, when it gets planted, it is going to mature at the same time of year due to the photoperiod.” 

            Vardiman noted the planting rate for hemp is variety dependent but recommended at 25 to 35 pounds. 

            “This really depends on what type of product we are growing the crop for. If we are growing for CBD oil, planting rate will probably be closer to fiber or seed production,” he said. “Planting depth is anywhere from a half inch to 1.5, and ideal soil temperature is around 50 degrees Fahrenheit.”

            Vardiman mentioned industrial hemp needs 20 to 30 inches of available water per year and fertilization is similar to corn.

Concerns for hemp production in Wyoming 

            Vardiman reminded producers growing hemp is currently still not legal in Wyoming.

 Although many are excited about the possibility of legalizing hemp in Wyoming, Varidman noted there are some concerns for producing hemp in the state that people should be wary of. 

            “One of the biggest issues with hemp production is what we call ‘plants going hot.’ This means THC levels rise above the 0.3 percent threshold,” Vardiman said. “If a producer has a crop of hemp go hot, they are turned over to the Drug Enforcement Administration (DEA) since they are now technically growing marijuana and the whole crop will need to be destroyed. How that is done is determined by the DEA.” 

            The next issue for growing industrial hemp in Wyoming, according to Vardiman, is isolation issues. 

            “If producers are planning on growing industrial hemp, they need to start talking to their neighbors,” he said. “If I am growing hemp for CBD production and my neighbor up wind is growing hemp for grain, they might throw me out of business because their pollen will be blowing down to fertilize my plants.” 

            He explained there will also be isolation issues for producers growing hemp for certified seed.

            “Weed management is going to be another huge issue, depending on what a producer decides to grow. If they grow for fiber or seed production in the field, they are going to be planting at very high seeding rates and utilizing this to outcompete the weeds,” he explained. “However, if a producer is growing for CBD oil, planting rates are lower and there will be tons of bare ground for weeds to grow.”

            “There are no herbicides labeled for industrial hemp so producers’ only option is to do a pre-plant burn prior to crop emergence and again after harvest which means weed management is going to be a challenge,” he said.

            The last thing Vardiman said might become a challenege is disease. 

            “Since we grow a lot of sugarbeets, beet curly top virus might be an issue,” he explained. “The virus is spread by the beet leafhopper insect.” 

            “The other disease is white mold. We see white mold show up in dry bean production, especially under pivots,” he said. 

            Hannah Bugas is the assistant editor for the Wyoming Livestock Roundup. Send comments on this article to

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