Duration: 10/01/2024 to 09/30/2029

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Hemp grown in the western US faces many unique problems from pests, diseases, and cultivation issues that differ from those when hemp is produced in other parts of the US. There are a variety of fungal root rots and viral diseases that infect hemp, and several insects and mites (e.g., corn earworm, cannabis aphids, hemp russet mite) that cause crop damage. For example, beet curly top virus, which is vectored by beet leafhoppers, caused significant losses (greater than 90%) to hemp fields in western Colorado in 2019. Beet leafhoppers are not pests in the central and eastern US states. Leafhoppers can also transmit Virescence Agent (BLTVA - group VI) in the western US, a phytoplasma that infects hemp, as well as Spiroplasma citri. Spiroplasma citri has been newly reported this year in western US hemp plants and has occurred in both fields and indoor grows. Research on hemp genetics and plant resistance to pests and diseases has been quite limited, and research in these areas is still in the initial stages; it has been only a few years since the 2018 Farm Bill was passed. Sustainable management programs for pests and pathogens of hemp are mostly in the research and development stages but will require an integrated approach that is only possible when individuals with different areas of expertise work together.

We propose the initiation of a WERA group to address hemp production problems through an integrated management approach. This committee will meet to discuss, assess, and prioritize research required in hemp genetics, pests/diseases and their management, hemp cultivation, and hemp processing. Individuals will share their best practices and research insights, which are critical benefits resulting from an active group of diverse plant scientists collaborating on a group-developed research agenda. The committee will coordinate action plans to determine who will accomplish which aspects of the needed research, including who will work together to seek funding for the highest priorities identified as necessary for research. The group will also coordinate research to provide preliminary information or base-line data necessary to secure grant funding.

Statement of Issues and Justification

Hemp (Cannabis sativa) has been produced legally in the US beginning with the 2014 Farm Bill and the 2018 Farm Bill allowed for the renewed legal cultivation of the crop. As a result, hemp is no longer listed as a Schedule 1 substance. The 2014 bill provided a formal definition of the crop as "the plant Cannabis sativa L. and any part of such plant, whether growing or not, with a delta-9-tetrahydrocannabinol (THC and THCA) concentration of 0.3 percent or less on a dry weight basis".

In much of the western US, this prompted a surge in industrial hemp cultivation. In 2019, hemp production was at an all-time high with 206,974 hectares planted and 16,877 grower licenses issued across 34 states, according to the "US Hemp Crop Report" (https://www.votehemp.com/u-s-hemp-crop-report/). This reflects a greater than a 554% increase over 2018 licensed acreage. Colorado, the leading state in hemp production, increased production from 4,873 licensed hectares (346 growers) in 2017 to 12,525 licensed hectares (835 growers) in 2018. However, the US hemp production acreage declined sharply over last two years, with totals of 21,914 and 11,458 hectares planted in 2021 and 2022, respectively (NASS, 2022 and 2023). The US retail sales of hemp products was reported at $824 million in 2021 (NASS, 2022). The most profitable market for North American hemp is currently oilseed production and cannabidiol (CBD), a nonintoxicant cannabinoid with promising therapeutic use as a pharmaceutical product.

Although there has been a decrease in acreage planted, markets for hemp products still exist and potential for additional products continue to develop. Thus, there has been and likely will continue to be a need for the development of information to aid the burgeoning hemp industry in the US, including the western US. However, hemp production in the US has led to a steep learning curve on factors that contribute to successful industrial hemp cultivation as well as major market adjustments for CBD/hemp products. This learning curve has included AES and CES personnel from states in the western US who had with no experience with the plant prior to 2018, its cultivation, or associated pest and disease problems.

Hemp is grown throughout the world, with optimal temperatures for growth listed as 60-80°F, and a sensitivity to day length for seed set (USDA, 2000). Much of the breeding work for hemp has traditionally been done in Canada and China. Hemp is a short day flowering plant and when grown in the southern USA, will be prone to premature flowering. These factors suggest that most hemp varieties that have been released to date are less suited for the warmer growing conditions in the southwestern US.

Unlike hemp grown in the US in the 1940’s, industrial hemp is now grown for three components: CBD, grain, and fiber, with other cannabinoids emerging (CBG, cannabigerol) for potential markets. However, in the western US, the CBD-types currently dominate hemp production. The lack of infrastructure for fiber and grain production, suitable varieties with genetic purity, and reliable sustainable sources of seed/clones as well as established markets have been major stumbling blocks for expansion of hemp production in the western US. CBD hemp production has generally relied on the use of clones while grain and fiber varieties are typically grown from seed. There are few pesticides currently registered for the crop, and the ones registered are “softer” chemistries, which leads to difficulties not only in the organic production needed for CBD hemp production, but also suboptimal control provided by registered pesticides when applied by conventional growers. This pesticide scarcity though, offers a perfect opportunity to develop and promote an integrated pest management system from the ground up for hemp producers across the western US.

Hemp grown in the western US faces many unique problems from pests, diseases, and cultivation issues that differ from those when hemp is produced in other parts of the US. There are a variety of fungal root rots and viral diseases that infect hemp, and several insects and mites (e.g., corn earworm, cannabis aphids, hemp russet mite) that cause crop damage. For example, beet curly top virus, which is vectored by beet leafhoppers, caused significant losses (greater than 90%) to hemp fields in western Colorado in 2019. Beet leafhoppers are not pests in the central and eastern US states. Leafhoppers can also transmit Virescence Agent (BLTVA - group VI) in the western US, a phytoplasma that infects hemp, as well as Spiroplasma citri. Spiroplasma citri has been newly reported this year in western US hemp plants and has occurred in both fields and indoor grows. Research on hemp genetics and plant resistance to pests and diseases has been quite limited, and research in these areas is still in the initial stages; it has been only a few years since the 2018 Farm Bill was passed. Sustainable management programs for pests and pathogens of hemp are mostly in the research and development stages but will require an integrated approach that is only possible when individuals with different areas of expertise work together.

We propose the initiation of a WERA group to address hemp production problems through an integrated management approach. This committee will meet to discuss, assess, and prioritize research required in hemp genetics, pests/diseases and their management, hemp cultivation, and hemp processing. Individuals will share their best practices and research insights, which are critical benefits resulting from an active group of diverse plant scientists collaborating on a group-developed research agenda. The committee will coordinate action plans to determine who will accomplish which aspects of the needed research, including who will work together to seek funding for the highest priorities identified as necessary for research. The group will also coordinate research to provide preliminary information or base-line data necessary to secure grant funding.

Related, Current, and Previous Work

Hemp is a relatively new crop for the US. Sales of hemp products in the United States have been growing at a very rapid rate since legalization of the crop with the 2018 Farm Bill. The market has been highly volatile, as one would expect with a new crop. The prices of CBD raw biomass, dried CBD flower, crude hemp oil, refined hemp oil, and CBD isolates originally soared but have all dropped since the 2019 harvest due to market saturation. However, the markets for hemp for grain and fiber are less defined in much of the US and are expected to grow substantially through the upcoming years as infrastructure fills in and markets of US-produced seed and fiber expand. For hemp to be highly successful, it will also have to provide expected returns equivalent to returns for competing rotational crops.

In addition, there is a highly structured permitting process with state and federal oversight, and sometimes local laws, governing production. There are some differences among states, but all US states require permits before planting hemp and testing for THC level prior to harvest. Also, in some states such as Oregon, the criminal background check is required as a part of licensing process. In some locations, local ordinances prevent growing hemp outdoors if it could pollinate cannabis (marijuana) crops.

Other concerns for hemp production include market development, storage conditions, and access to reliable seed or clones. While some of the hemp being produced is done on a contractual basis, in many other situations, the market is not well established. Most of the contracts do not pay the producer until the processor has sold its final product. In addition, hemp for grain, fiber, and CBD needs to be stored until it is time for such products to be used or readied for marketing.

For grain and fiber crops, conventional production practices generally use direct seeding into fields. In contrast, CBD hemp production typically utilizes clones which are transplanted into greenhouse or field settings. CBD hemp is often grown using organic production practices since the CBD could be consumed, in addition to market demands for certified organic products. Furthermore, there are very few herbicides, insecticides, or fungicides currently labeled for use in hemp. Registration of pesticides for fiber, and possibly grain hemp, are being pursued through the IR-4 program while special local need registrations are also a potential route. Safe-use patterns for pesticide applications in hemp and around hemp are also sorely lacking.

Access to certified hemp seed and clones adapted to the western US is limited for many producers. Much of the current germplasm has been developed in northern latitudes and leads to premature flowering in warmer southern latitudes. Genetic selection is very important because some clones grown for CBD extraction contain levels of THC that are illegal at harvest under the existing standards (<0.3% ceiling currently), necessitating destruction of the crop. Compliance with THC levels is less of a problem for grain and fiber producers but requires that they have a reliable seed source with decreased heterogeneity within varieties. Harvest can be challenging for producers as there is a 30-day harvest window that begins with the final regulatory test for THC levels, which can cause time constraints due to labor intensiveness of harvest for CBD hemp.

The hemp industry in the western U.S. needs thorough crop evaluations. Efforts to better understand yield potential, production factors, harvesting methods, handling, storage, and processing for crops grown in the region are essential for improving the sustainability of production. Also, hemp is not adapted to desert environments and cultivation of the plant under hot, arid field conditions needs additional research.

Industrial hemp is produced for three components: 1) CBD, 2) fiber, and 3) seed/grain. Currently in the western US, little of the crop is grown for fiber or seed/grain.

• CBD hemp

Cannabinoids have been used for many potential medicinal properties including aiding sleep and pain relief. The flower buds of unfertilized female hemp plants are used for extraction of CBD and marketed as smokable flower buds. Similar to marijuana cultivation, plants typically begin from clones of feminized plants. Efforts are made to remove any male and hermaphrodite plants found in stands, and to discard any female plants that have produced seed. Light intensity is manipulated to achieve optimal flower bud production indoors. Plants grown outdoors are generally harvested in September to early October. However, much of the hemp grown for CBD in the southern USA is grown in controlled environment greenhouses, hoop houses, or grow rooms. Usually, the levels of THC increase with increased CBD levels (but depend also on plant genetics), and plants are usually harvested by hand based on laboratory testing of CBD/THC levels to avoid illegal levels of THC. After harvest, the plants are trimmed, dried, and stored.

2) Fiber hemp

The stalk of the hemp plant is largely used for fiber. Fiber from the plant can be utilized in numerous ways ranging from yarn and fabric to paper to electrical super-capacitors manufactured from carbon nanosheets; hemp-crete is another important potential market. While traditional use of the fiber was for rope/cordage, it is not currently cost effective to use hemp fibers for products that are generally imported more cheaply from China.

Dioecious hemp crops produced for fiber are usually harvested when the male plants have finished flowering, typically in August to September. Traditional haymaking equipment can be used for hemp fiber harvest, but cuts the fibers into shorter lengths (Ehrensing, 1998). Harvesters and collection systems developed for cotton have been used experimentally for collecting hemp fibers, since the plants are less tangled during harvest using these methods. These systems also require less handling through the collection and processing stages, allowing for longer fiber lengths. This requires modification of the harvesting equipment, but in areas already producing cotton, the equipment is available. Prior to processing, the hemp fibers must be decorticated. The decortication process for hemp mechanically removes the tough woody interior (the hurd material) from the softer, fibrous exterior of the stalk. In wetter areas, this process (retting) can be done in the field with water over 1 to 6 weeks, depending on temperature. Equipment for mechanical decortication and fiber processing is not readily available in much of the western US near where hemp is grown, thus increasing costs associated with hauling hemp stalks to a processing facility. Ultimately the optimum fiber harvest system will depend on the market value of hemp fiber.

3) Seed/grain hemp

Hemp seed is sold as grain and for oil extraction and animal feed.  Hemp grain is relatively high in oil content, generally containing 30% or more by weight. This oil is very healthful as a dietary constituent or supplement for humans. It is rich in omega-3 fatty acids and has a very favorable omega 3 to omega 6 ratio of about 3:1. This is much higher than that found in many other oil seeds. The grain is also high in protein and contains all 20 amino acids (Russo and Reggiani, 2015).

Hemp grain processors in Canada produce a wide array of consumer products including toasted hemp seed, hemp seed oil, hemp flour, and even hemp coffee.  It is also used as bird feed and livestock feed, either whole or in part (as a high protein hemp seed meal and hulls), much the same as soybean meal and hulls are used today. Hemp grain is an important commodity crop in Europe, where approximately 80% of the grain is used as animal feed. In the US, however, there is still controversy about the use of hemp seed as animal feed and the American Veterinary Medical Association warned in 2022 against the use of hemp seed and hemp oil in animal feed until studies show that the use is safe (https://www.avma.org/news/organizations-warn-against-hemp-pet-food-livestock-feed).

Harvesting industrial hemp grain by combine is the norm in other countries and has been successful in the northern US. Varietal selection is key as the growth habits of hemp lines bred primarily for grain production are more conducive to harvest by combine. Crops grown for seed oil production need to be harvested once seeds are mature. After harvest, the grain is cleaned and dried to prevent spoilage.

The “S1084: Industrial Hemp Production, Processing, and Marketing in the US” regional project has addressed portions of this topic. However, this project, which ran through 9/30/2022, focused on hemp production in the southeastern US, which has very different growing conditions compared to the western US. Hemp grown in the western US has different cultural, pest, and disease problems relative to hemp grown in the southeastern US. 

Our WERA group was developed after a meeting in 2022 of the Western Hemp IPM working group (funded by the Western IPM Center). That working group already contained sustainable collaborations among group members and sharing of information.  For example, the Nachappa and Creamer labs have been involved in studying the ecology, epidemiology, and disease mitigation strategies for beet curly top virus in hemp (funded by FFAR - Foundation for Food and Agriculture Research).

Objectives

Procedures and Activities

1. Assess the current status of hemp cultivation and management and set priorities for integrated research on hemp pest/pathogen management and cultivation in the western US.

We will bring together individuals working on different aspects of hemp cultivation and pest /disease management in the western US annually to improve communication among the various disciplines. At a meeting sponsored by the Western IPM Center in October 2022, the group included plant pathologists, weed scientists, entomologists, plant breeders, and extension scientists from New Mexico, Nevada, California, Colorado, Wyoming, Utah, Nebraska, Oregon, Montana, and Washington. The group included AES researchers, CES scientists, and growers/industry representatives. The coordinating committee will meet yearly to discuss the status of hemp in the western US and present the latest developments in research. At the annual meetings, the group will also discuss gaps in the knowledge of the crop and its pests and management and set priorities for research.

A subset of the group met online through zoom in 2019-2020. An in person/hybrid meeting was held on October 11-12, 2022, in Fort Collins, CO. There were 31 participants including post-docs and students. Talks, posters, and a panel discussion presented information on viral and fungal diseases, herbicides, grasshoppers and other insect pests, new products, hemp cultivation/field trials, agronomy of hemp, insect vectors of pathogens, and hemp products.  One outcome of the meeting has been the collaborative development of educational/extension videos on different aspects of hemp IPM including diseases, insects, curly top virus, and cultivation of hemp in the western US.

 

2. Characterization of biology of hemp pathogens, insect pests, nematodes, and weeds, including identification, genetic diversity, and detection.

 

The ability to manage a pest or pathogen requires an understanding of its biology and a method to identify it. There are very few published papers on the pests and pathogens of hemp in the western US. There are a few book chapters, extension guides, and bulletins on the topic. There is limited information on how the pests and pathogens behave on other crops in the western US or in other areas of the US, China, and Canada.

However, within cooperating western states, there are efforts underway to study a few key pest and pathogens. For example, the Nachappa lab confirmed beet curly top virus in over 150 hemp samples from 9 counties in Colorado, with several fields reporting disease incidence levels above 50%. This led to diminished crop yield, including low quality of the flower and overall stunted growth. Interestingly, only BCTV-CO and BCTV-Wor strains were found to be infecting hemp (Chiginsky et al. 2021). The Creamer lab worked with the Nachappa lab to monitor beet curly top virus and its vector, the beet leafhopper, in New Mexico. This group also found diminished crop yield and low quality, and only BCTV-Wor and BCTV-PYD strains of the virus (Creamer et al. 2023). The group will continue to share information on viral genetic diversity and sequence the genome of curtovirus isolates collected from different states. The compilation of this information is also essential for effective development of management systems.

There are pest and disease surveys of hemp ongoing in many western states, but these need to be shared among group so that all group participants are aware of potential pests and pathogens. For example, many states found that the soilborne fungus Fusarium caused root rot disease, but only in specific environmental conditions. Some states found that hemp russet mites caused significant problems, while others had much worse losses from grasshoppers. Arizona found whiteflies, flea beetles, beet armyworms, corn earworms and beet leafhoppers as common insects pests. Oregon found corn earworms, cannabis aphids, thrips and lygus bugs are common insect pests. Nevada identified powdery mildew, Botrytis blight, viruses, Phytophthora causing stem canker, Fusarium causing vascular wilt and root rot, nematodes, mites, and aphids as the most common biotic agents causing problems for industrial hemp. Researchers in Oregon have identified two different fungi involved in powdery mildew outbreaks in Oregon and Washington (Rivedal et al., 2023) as well as detected beet curly top virus, hop latent viroid, phytoplasma, and spiroplasma in hemp produced in these two states. Also, root-lesion nematode and northern root-knot nematode have been found parasitizing hemp in the Pacific Northwest region.

 

3. Organize research on the ecology and epidemiology of the pathogens and their insect vectors and transmission, insect movement, and the role of weed hosts in carry-over of insect and pathogens of hemp in the western US.

Certain pests and pathogens have been studied for their association with other crops, however this type of information needs to be determined for hemp. For example, while much research has been done to determine the beet leafhopper host range, the biology and its ecology in specific locations differs with crops and weed populations. Research to assess how the leafhoppers are overwintering has been done for some states, but not others; and similarly, leafhopper flight patterns have been studied in some areas and not others. The Creamer lab found that BCTV was much more of a problem on CBD hemp than grain or fiber hemp varieties, and the pathogen was more prevalent in the warmer environments preferred by the leafhopper vector. Several labs have studied the feeding preference, or lack thereof, of the beet leafhopper for different varieties of hemp.

There are many reports on the weeds hosts of beet curly top virus and its leafhopper vector. However, many of these reports are historical, and the weed species composition and populations have evolved over the time in the last 50 to 80 years, since the reports were published. Data on the movement of leafhoppers from weed host and other crops to hemp could be incorporated into predictive models.

4. Organize research to improve management of pests, pathogens and weeds of hemp important in the western US with an emphasis on integrated pest management approaches.

There are essentially no conventional “hard” pesticides registered for industrial hemp. There are a few biologicals that can be used along with limited elemental types (copper, potassium bicarbonates) and plant extracts. The viruses and viroids infecting hemp are unlikely to be managed effectively by pesticide applications. Rather, cultural controls and biocontrol formulations will be key to management of viruses/viroids in hemp in the short term. Long term possibilities include herbicides or fungicides along with host resistance, but these will need to be evaluated.

As an example, BCTV has proven to be very difficult to control. Possible methods to manage the disease including biocontrol of the leafhopper vector; insecticide sprays; use of anti-transpirants to deter leafhopper feeding; effective trap crops and/or row covers to deter insects; identification of plant resistance to virus and leafhoppers; engineered resistance; and predictive modeling to determine the likelihood of curly top in the next growing season and timing of beet leafhopper flights.

Management tools or knowledge developed in other crops might be transferred into hemp. The Nachappa and Creamer labs have monitored beet leafhopper movement in New Mexico and Colorado to develop predictions models of leafhopper population and virus dynamics in hemp. This project was funded by FFAR (Foundation for Food and Agriculture Research). Previous work by the Creamer lab showed the effectiveness of kaolin clay in deterring beet leafhopper feeding on organically grown tomatoes. It is possible that this product could be effective in hemp as well.

5. Organize research on hemp cultivation in the western US, including factors such as seed/clone selection, transplant difficulties, irrigation, nutrient management for specific regions, heat stress, early maturity day length issues, and excess THC levels.

 

Since much of the current varieties of hemp seed for grain and fiber have been developed for use in northern latitudes, these lines are not adapted for use throughout the western US, particularly the hotter, drier southwestern US region. To avoid premature flowering in southern latitudes with less day length variation for this short-day flowering plant, screening of different varieties of hemp and sources will need to take place in different locations. This is particularly important for hemp grown for CBD which is specifically not grown for seed production. 

 

Genetic selection is very important because some clones grown for CBD extraction contain illegal levels of THC (>0.3%) at harvest, necessitating destruction of the crop. Similarly, different clones will be tested in different locations to determine which varieties work best under various environmental conditions. Also, nutrient and irrigation regimes that are tailored for specific climatic zones within the western US need to be developed and supported by research driven processes. Furthermore, some varieties express higher heterogeneity than is generally suitable for production, and development of assays for accessing heterogeneity would be valuable to hemp producers.

 

Production indoors or under controlled environments such as hoop houses is often used for CBD hemp when the outdoor temperatures are very hot or for use in urban environments. Many growers prefer the ‘indoor’ option to avoid dust and grit, to have full control over the environment, and to expand the growing season to year-round cropping. The addition of hemp as a regular component of urban agriculture also expands the range for hemp growth. Determining the optimal conditions for growth of hemp for ‘indoor’ growth is essential for expansion of CBD hemp production.

 

Other aspects of hemp production that hold potential are the integration of hemp into a crop rotation plan. Which crops will most readily go into a rotation with hemp, keeping in mind the growing conditions and pest complexes of both crops?

 

6. Organize research on hemp production at and after harvest in the western US including factors such as harvest and extraction of CBD, storage conditions, equipment necessary for harvesting grain hemp, equipment needed for processing fiber hemp, and marketing essentials.

 

Timing of harvest needs to be studied more for CBD varieties. There is a 30-day harvest window clock that begins with the final regulatory test for THC levels, which can cause time constraints due to labor intensiveness of harvest for CBD hemp. A market for the final CBD hemp must be identified prior to obtaining the clones.

 

Harvest of grain hemp is done by combine but may require modifications in spacing of tines and result in potential problems due to the stickiness of hemp plants. In addition, contracts need to be set prior to planting to determine specifications required, and scheduling access to harvesters and seed driers.

 

Harvest for fiber hemp can be done using a mower or haybine. The stalks can be retted in the field and then baled for shipment to a processor. However, there is a lack of processors in many areas of the US, including the western US. Alternatively, access to cotton harvesting equipment may prove to be useful for hemp fiber crops. All these factors need study to determine which types of hemp, harvesting, and processing will be most economically feasible for different areas within the western US. Access to fiber processing facilities for hemp are essential for fiber hemp to be marketable in the western USA.

 

7. Provide a regional platform for education on hemp, pathogen and pest ecology and management, hemp cultivation and processing, and collaboration among scientists involved in these activities, and extending research-based information to producers and other industry members.

The group has accumulated much information on various aspects of hemp, and actively disseminated the information as it has been generated. General practical information on the crop, its cultivation, and pest management is not available in a single location. Often, the information that is available is specific to a particular location. The group, with directed input from the industry members, will develop best practices recommendations, both general and specific, for hemp grown in the western US.

The group will utilize a website previously developed for the previously funded Western Hemp IPM working group to house information and the best practices recommendations developed by the group. Just as important, the group plans to add new information as it becomes available, keeping the information current. 

The meetings of the group will provide an opportunity for undergraduates and graduate students as well as post-docs working on hemp to present their research and to meet other established researchers. 

The group will coordinate activities and information sharing through two groups which members already have collaborated and worked with. The Global Hemp Innovation Center at Oregon State University has agreed to collaborate with our effort and will begin by hosting some of the videos that we produced on Hemp IPM as part of the Western Hemp IPM working group. They will also link to the webpages developed by this group. We will also collaborate with the Institute of Cannabis Research at Colorado State University. Collaborating with both groups will help us avoid duplication of efforts, particularly as it relates to providing information on hemp to the general public.

Outputs:

The implementation of this proposal will result in annual meetings of the WERA hemp group. At meetings, research progress reports will be presented, graduate students and post-docs will present their research, and priorities for needed research into hemp cultivation and IPM will be identified. An annual action plan will be developed to determine which components of the group will accomplish specific aspects of the needed work. Subgroups of the participants will be formed to work on specific projects throughout the year, including educational materials, presentations, and reference sheets.

It is expected that preliminary research will be coordinated to obtain information needed to secure grant funding. Several members of the group will focus on submitting a large grant such as SCRI (Specialty Crop Research Initiative), CAP (Coordinated Agriculture Projects) or AFRI SAS (Sustainable Agricultural Systems) grant programs.

A transcript of all meeting discussions will be made available to all committee members and interested individuals. Best practices management recommendations, both general and specific, will be developed.

Expected Outcomes and Impacts

Projected Participation

View Appendix E: Participation

Educational Plan

All participants will disseminate information discussed at field days, grower meetings, extension publications, and web sites (GHIC, ICR, and this project). Growers, crop consultants, and extension personnel members of the group can help disseminate the information to their constituents and clientele. Transcripts and/or recordings of all meetings will be made available to all interested individuals upon request. We will post the educational videos produced on hemp IPM on the website so that they can be viewed by the general public.

Collaborations with The Global Hemp Innovation Center at Oregon State University and the Institute of Cannabis Research at Colorado State University will allow us to extend our delivery of information. The Institute of Cannabis Research puts on a yearly conference, which in 2024 is cohosted by the Global Hemp Innovation Center, that allow us to educate those in the industry in a very targeted manner.

Organization/Governance

An Executive Committee made up of the chair, local arrangements chair, and secretary will serve as the governing board. The committee will also help plan meetings and write relevant reports. The Chair position will rotate among members annually and will transition each year at the annual meeting. Local arrangements chair for annual meetings will also be rotated among participants. Dr. Rebecca Creamer will initially serve as the secretary, keeping the email listing of participants, and maintaining all pertinent documentation.

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Pitt, W.J., Kairy, L., Villa, E., Nalam, V.J., and Nachappa, P. 2022. Virus infection and host plant suitability affect behaviors of cannabis aphid (Hemiptera:Aphididae), a newly described vector of potato virus Y. Environ. Entomol. 51:322-331.

Rivedal, H.M., Temple, T., Thomas, W.J., Ocamb, C.M., Funke, C., Skillman, V., Jackson, R., Jones, G., Shrestha, G., KC, A., Dung, J.K.S., and Frost, K.E. 2023. First report of Spiroplasma citri associated with disease symptoms in field-grown hemp (Cannabis sativa L.) in the Pacific Northwest. Plant Dis. 107:https://doi.org/10.1094/PDIS-07-23-1419-PDN. First Look: Online ahead of print.

Rivedal, H.M., Wiseman, M.S., Richardson, B.J., Massie, S.T., Garfinkel, A.R., Ocamb, C.M., and Gent, D.H. 2023. Characterization of powdery mildew fungi affecting hemp in the Pacific Northwest. PhytoFrontiers 3:https://doi.org/10.1094/PHYTOFR-07-23-0099-R. First Look: Online ahead of print.

Rondon, S.I., Roster, M.S., Hamlin, L.L., Green, K.J., Karasev, A.V., and Crosslin, J.M. 2016.  Characterization of Beet curly top virus strains circulating in beet leafhoppers (Hemiptera:Cicadellidae) in northeastern Oregon. Plant Dis. 100:1586-1590.

Russo, R., and Reggiani, R. 2015. Evaluation of protein concentration, amino acid profile and antinutritional compounds in hempseed meal from dioecious and monoecious varieties. Am. J. Plant Sci. 6:14-22.

Solomon, J., Ogunleye, A., Opoku, A., Barrios-Masias, F., Huber, S., and Foster, S. 2022. Industrial Fiber Hemp: An Early Initiative to Capture Varietal Response in Nevada, Extension, University of Nevada, Reno, FS-22-11. On-line at https://extension.unr.edu/publication.aspx?PubID=4776

USDA 2000. Industrial Hemp in the United States: Status and Market Potential. https://www.ers.usda.gov/publications/pub-details/?pubid=41757

Attachments

Land Grant Participating States/Institutions

CO, MT, NM, NV, OR

Non Land Grant Participating States/Institutions

University of Nevada