The University of Kentucky is Casting a Wide Net in its Hemp Research

Departments - Smart Start Research Roundup

Bob Pearce, Ph.D., of the University of Kentucky’s College of Agriculture, Food and Environment shares insights into ongoing studies on optimal hemp production practices with a goal of creating a sustainable industry.

October 7, 2020

Photos courtesy of Bob Pearce

When the 2014 Farm Bill and, more broadly, the 2018 Farm Bill, allowed hemp to be grown in Kentucky for the first time in over 50 years, the crop captured the interest of many of the state’s farmers, which led the University of Kentucky to launch the research needed to support the state’s growers.

“We wanted to make sure that we started to work on developing the information that we needed in order to help advise growers in learning about this new opportunity for an old crop,” says Bob Pearce, interim director of hemp programs at the university’s College of Agriculture, Food and Environment.

Pearce, an extension professor who primarily specializes in tobacco, has established agronomic studies centered on many aspects of hemp production, such as fertility, weed control, ideal planting depth and optimal planting dates and cultivars for the region.

Bob Pearce, interim director of hemp programs at the University of Kentucky’s College of Agriculture, Food and Environment, is conducting a variety of studies on hemp cultivation.

His team also works with plant pathologists, entomologists and economists at the university to study disease control, insect management and economic viability in hemp production systems.

Pearce has cast a wide net with his early studies, and he plans to continue refining the research as his team learns more about hemp.

“It’s been a learning curve for all of us, really, in learning how to work with this crop,” Pearce says. “During the last couple years, we are getting some of the basics of how to best go about planting this crop, … so now I think we’re beginning to get to a point where we can design some more specific objectives of what we want to learn.”

With a couple years of experience under his belt, Pearce is looking more closely at the ideal planting date for Kentucky’s climate, as well as planting depth.

“There may be an interaction between those two things, too,” he says. “As the soil warms up in the spring, the optimum planting depth may change over time. We’re interested in looking at that from the standpoint of germination of the crop and its competitiveness with weeds.”

At this stage, Pearce and his team have conducted a few preliminary experiments on planting depth, and they plan to add planting date components to the studies next year to help make better recommendations for growers.

Studying different hemp cultivars is on the research docket as well. The University of Kentucky has long studied hemp for grain and fiber applications, with fiber trials taking place every year since 2014 and annual grain trials launching in 2015. Obtaining seed for trials has been a challenge, so the trials were limited to just a few cultivars early on but have recently expanded to 12 to 15 cultivars.

Pearce has also helped to coordinate a national trial in which 12 hemp cultivars are being grown in roughly 13 states in 2020 to see which ones are best suited for different regions of the country.

“We know that probably not all cultivars are going to be well-adapted to all of those locations, but it starts to give us some ideas about which cultivars are going to be better adapted to some areas than others, and then we can start to maybe work with breeders to select for traits that are specific adaptations for certain regions,” Pearce says.

The University of Kentucky is trying to gather as much information about the cultivars as it can during these trials, Pearce adds, including germination, plant height, yield and other measures to evaluate the plants’ overall growth and health.

A Long Journey

The bottom line, Pearce says, is that the university is just starting to embark on a long journey to research the agronomy of the plants, and the studies will continue to evolve over time.

“As we learn one thing, it leads to additional questions and fine-tuning,” he says. “I think we have to realize we’ve got quite a long way to go with hemp production practices in the United States because hemp was not grown for 70-plus years here. No production research was conducted on hemp due to the fact that it was considered a Schedule I drug for many years.”

This is in stark contrast to other crops, such as corn and soybeans, which have been researched for many years. Their production practices are still being fine-tuned through numerous studies in the U.S.

“Assuming that hemp’s still going to be around, this is going to be a long-term process to try to improve the practices,” Pearce says. “If there’s an industry and an interest to support that research, then we’ll be able to continue doing the research.”

In these very early stages, Pearce says he and his team are still learning all the time, as each year presents new challenges and findings.

“When we first started looking at direct seeding of hemp in this region, we started out planting really shallow because we wanted the hemp to germinate quickly and out-compete the weeds. Now I’m starting to think that maybe shallow planting depth might not be the best thing,” he says. “That’s why we’re starting to look at planting depth in a little more detail [to] better understand all of the processes that go into establishing a stand of hemp from seed.”

As with any long-term project, the research hasn’t been without its challenges. One hurdle, Pearce says, is keeping protocols consistent, which has been difficult in a new industry, where the team has been unable to get access to the same cultivars year after year.

“The industry is changing very rapidly,” he says. “There have been a lot of companies coming in and out of the business in the last couple of years, so just trying to develop those relationships has been a challenge, as has … getting access to the same seed sources. Some of the older cultivars that we’ve been using are cultivars that maybe came from Europe. It’s been a challenge sometimes to know who actually owns the rights to specific cultivars, and whether or not you are actually getting the cultivar that is listed on the label. This will get better as seed certifications are put in place for hemp.”

To be able to publish the studies’ findings in refereed journals, consistent methods must be established, Pearce says. In the meantime, the team has been posting general updates and reports on the university’s website.

Funding is often another challenge for Pearce and his team.

“It takes money to run a research program, and up until just recently, there hasn’t been much prospect of any federal money to do that,” he says. “A lot of the entities in the hemp world are start-ups, so they don’t have a lot of money to throw around at research. … It’s been a challenge to figure out how to fund a program and maintain it.”

Overall, Pearce aims to help growers meet industry needs through producing an in-demand product, whether it be grain, fiber, cannabinoids or something completely different.

“The base of [the] supply chain is the grower,” Pearce says. “The goal is for us to be able to instruct that grower on how to be able to consistently produce a product that the industry desires … year in and year out, and for it to be economical so that the grower can get paid enough to make it worth their while. Then, the product moving into the supply chain [must be] competitively priced with competing products in the marketplace. Ultimately, the goal is to create a sustainable industry, and that starts with the raw product.”