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A medical cannabis growing operation in Oakland, California.

A medical cannabis growing operation in Oakland, California.

Rusty Balenhoff/Flickr (CC BY-NC 2.0)

Q&A: Why pot law changes are creating headaches for farm researchers

The growing push to decriminalize pot by U.S. state governments is putting many farm scientists in a bind. That’s because federal law bars researchers who work at federally funded institutions from giving pot growers the same kind of assistance they routinely offer to other kinds of farmers.

The result, says plant physiologist Angus Murphy of the University of Maryland (UMD), College Park, is that farmers may not be getting the advice they need to grow the controversial crop safely and effectively.

The federal government lists cannabis as a Schedule I drug, considered the most dangerous, and yet the plant is now legal in some form in 23 states and the District of Columbia. Maryland, for example, allows clinics to dispense medical marijuana. Twelve more states may vote on pot issues in the next year.

The contradictory laws are posing problems for some academics, particularly at the nation’s some 100 land grant universities—public institutions created to provide practical education in agriculture, among other fields. Many of these schools operate so-called extension programs, which are cooperative efforts between federal and state governments to help support agriculture. Extension researchers often spend a lot of time with local farmers, educating them on how to incorporate the latest science.

But because pot is illegal, extension staff often can’t advise growers on the best practices for growing the crop, which could include how to use pesticides effectively and safely, and how to manage fertilizers and water to minimize environmental impacts.

ScienceInsider recently spoke with Murphy, the chair of UMD’s Department of Plant Science and Landscape Architecture, about the issue. (The conversation has been edited for length and clarity.)

Q: For a more typical crop, how would your university interact with a farmer?

A: I think we have to narrow it down a little bit, because [cannabis cultivation] is what you call contained environment growing. Some people refer to it as nursery growing or greenhouse growing, but it’s really a contained environment. It’s a somewhat specialized field and usually it is something that pertains to horticultural crops, floriculture, hydroponic tomatoes, things like that.

Q: So for contained environments, how would you normally interact with growers?

A: We deal with four things. One is: What are the latest technologies for limiting energy costs? That’s a very big part of it—lighting, heating, what have you.

Secondly, pathology. What do you do about insects, fungi, and bacteria? Contained environments have two things going. One is that you can try to control what’s coming in, so that’s a plus, but the second is that once [a disease or pest is] in there, it’s hard to get rid of.

The third part is testing and introducing cultivars. Is there a tomato that grows better in in this type of greenhouse? Are its yields less affected by common problems in greenhouse growing?

The last piece of the puzzle is nutrients and water use, runoff, treatment, what have you. These operations are intensive and we’re no longer willing to have all that going down the drain.

Q: Some universities in states with legalized cannabis have issued statements saying their academics can’t work with the industry. Has that happened at UMD?

A: We have to say that. If a person is funded by federal money in any way, or their facilities are funded by federal money, then it is illegal to use those facilities for cannabis production or for advising people on cannabis production. So we really can’t do it.

There’s definitely some conflict. For instance, we have two University of Maryland faculty members on the Maryland Medical Cannabis [Commission], and that had to be worked out very, very carefully. I’m serving to advise our folks as to what they can say and not say. They can’t support those operations in any way.

On the other hand, there are operations where we are giving them preliminary information, just in general. We’re providing the standard information we would be providing to someone who is growing holy basil or anything else. We have to draw a very careful line, because otherwise we’re going to fall afoul of federal law.

Q: Are there tough choices that you’ve had to make?

A: What’s really tough is a grower who is one of our regular folks—let’ say, who is growing for the nursery industry and is growing greens and things for farmers markets—[and] who wants to get a cannabis permit. They’d like to compete for this because they see it as good money. Well, these are people we’ve been supporting for a long time, and we obviously don’t want to see global corporations who are investing in this sweeping in. Our local guys have no chance to compete. That’s where it hurts.

Q: What are some of the other big concerns? For example, pesticides?

A: I think part of the problem is that normally the [Environmental Protection Agency] and [the Food and Drug Administration] have regulations that are promulgated on the federal level. At the state level, we adapt to [those rules]. We don’t have that with cannabis because the federal government just says it’s illegal. So we don’t have the capacity to [adapt] because [the rules are] not there.

That’s something that I’m worried about. As of now, it’s an issue we would call emergent. It’s probably more involved right now in the home grower type of situation. There are people who are claiming that they are growing [pot] completely organically in Colorado, [but] there are no real organic standards for cannabis growing.

Q: Why is the homegrown stuff more worrisome? Because the people doing it don’t necessarily have the pest management background compared with someone who has worked in a greenhouse?

A: Anyone who is applying pesticides in greenhouses has training. In every state the land grant institutions, or the department of agriculture, have the responsibility to train pesticide applicators. A professional applicator doesn’t put down any more than what’s needed, whereas typical homeowners figure: “Well, if you’re supposed to put down a quart, put down a gallon.”

Q: Because of this discrepancy between federal and state law, what’s the greatest risk for people who are trying to grow cannabis?

A: If they are not fully aware of the possible safety and toxicity issues with the application of pesticides in a restricted environment—because these aren’t even greenhouses with venting, these are closed warehouse buildings—there is a potential for [harm].

Q: How about for cannabis consumers?

A: The famous example is when we had marijuana coming from Mexico and from South America [in the 1970s]. The U.S. government sprayed it with paraquat, or paid local governments to spray with paraquat, and that resulted in people getting sick. The paraquat made people very ill. On the other hand, in our current situation, the growers will tell you that they make a large effort to avoid spraying the parts that are consumed. I don’t know if they can actually back that up, but that is what they say.

Q: Anything else you wanted to add?

A: Our job is to support agriculture, but as of right now one of the reasons that [our work] is not going any further [with cannabis is] because it’s not legal. So that ends it right there.