The corn earworm (Helicoverpa zea) is an rising pest of economic hemp manufacturing all through the U.S. Boring via stalks and feeding on reproductive buildings, this pest presents a number of administration challenges for hemp producers. Whereas built-in pest administration methods for extra conventional agricultural crops are established, a lot work continues to be wanted to develop efficient IPM for the corn earworm in hemp. Proven here’s a corn earworm larva feeding on a hemp plant flower bud. (Photograph initially printed in Britt et al 2021, Journal of Built-in Pest Administration)
By David Coyle, Ph.D.
David Coyle, Ph.D.
Cheech and Chong. The Massive Lebowski. Seth Rogen. These Hollywood legends helped thrust Hashish sativa into modern-day popular culture, making it concurrently well-known and notorious. And whereas the subject of C. sativa tends to elicit a spread of feelings and opinions, there isn’t a debating the actual fact this plant has many, many attributes and qualities.
Hashish sativa is an annual herbaceous crop native to east Asia however is now grown worldwide and will be cultivated for quite a lot of functions. Hashish sativa is understood colloquially as hemp or marijuana; these are completely different cultivars of the identical species. The distinction between hemp and marijuana is only chemical: marijuana has a excessive THC (tetrahydrocannabinol, aka the intoxicating half) content material, whereas the THC content material in hemp, by definition, should be lower than 0.3 %. There are additionally some bodily variations, as marijuana and hemp grown for cannabinoids have extra of a bushy, horticultural crop look whereas hemp grown for grain or fiber seems extra like a row crop, rising from a tall singular stalk.
Kadie Britt, Ph.D.
Hemp turned a authorized crop with the passage of the 2018 Farm Invoice (the Farm Invoice is now referred to as the Plant Safety Act, or PPA 7721). This motion was vital, because it was the primary time hemp was legally differentiated from marijuana. Whereas the regulation positioned restrictions on its manufacturing and use, the legalization of business hemp (as it’s recognized) led to a number of pilot manufacturing packages being initiated.
Since industrial hemp had not been cultivated within the U.S. earlier than, pest administration on this new crop was an space in dire want of analysis. A number of well-known pests current challenges to hemp cultivation, together with the corn earworm (Helicoverpa zea). An article published in September in the Journal of Integrated Pest Management highlights what we do and don’t find out about H. zea administration in industrial hemp. I spoke with the lead writer, Kadie Britt, Ph.D., postdoctoral scholar on the College of California, Riverside, about challenges and alternatives related to this well-known corn (and now hemp) pest.
Coyle: Do you assume hemp will take off? I imply, will we even have the infrastructure to help this trade?
The corn earworm (Helicoverpa zea) is an rising pest of economic hemp manufacturing all through the U.S. Boring via stalks and feeding on reproductive buildings, this pest presents a number of administration challenges for hemp producers. Whereas built-in pest administration methods for extra conventional agricultural crops are established, a lot work continues to be wanted to develop efficient IPM for the corn earworm in hemp. Proven here’s a corn earworm larva that has tunneled right into a hemp plant stem. (Photograph initially printed in Britt et al 2021, Journal of Built-in Pest Administration)
Britt: Sure and no. There’s a market, however there’s already an excessive amount of planted acreage, and the market is saturated. 2019 was an enormous yr after legalization in 2018, and a few growers nonetheless have that materials of their barns as of summer season 2021. Hemp could be very helpful, and there’s a really constructive long-term future with this crop when it comes to grain and fiber. The fiber can be utilized for a lot of issues, together with plastics, garments, rope, and a bunch of different issues. The grain can be utilized as a meals (assume Complete Meals fancy spices part) and has very useful fatty acids. Sadly, we nonetheless see an excessive amount of cannabinoid and never sufficient grain or fiber acreage.
Relating to administration, is it truthful to say there are extra questions than solutions at this level?
Sure! Each reply appears to result in extra questions. Can we pattern for pests in hemp as we do in different row crops? Sure, sampling is comparable, however with nuances. As an example, pheromone traps don’t appear to be efficient, so we’ll must develop one thing else. The takeaway is that it’s troublesome to rely solely on chemical management, and one of the best factor we are able to do or advocate at this level is to look at for eggs and larvae and to provoke spray purposes with a product authorized to be used in hemp. Weekly spraying will be efficient however targets solely corn earworm—a extra IPM-friendly method is required, however first we have to know extra concerning the system.
What are the largest administration challenges for industrial hemp?
There are such a lot of! Pest administration is a big problem, however growers want to have the ability to efficiently produce the crop first. Proper now, there’s an absence of infrastructure for the crop as an entire. Industrial hemp is a reliable various to many merchandise; something from cloth to plastic will be created from hemp. Some firms are constructing processing amenities, equipment, and all the opposite infrastructure vital for a brand new crop. Having correctly labeled pesticides obtainable is a problem, as industrial hemp most likely received’t garner the eye of big chemical firms, however smaller, newer biopesticide firms could also be extra keen, as will these that concentrate on specialty crops.
Any closing ideas?
Sure, the trade is new and rising, and we now have to comprehend that federal legalization of high-THC hashish will doubtless occur at one level. The work we do now will solely assist put together us for that point. Hashish is right here to remain, and pest susceptibility enormously will increase when the crop is grown in a monoculture sort of manufacturing. Industrial acreages are completely different than yard rising operations. Any data we get now will solely assist future C. sativa growers, whatever the closing product.
David Coyle, Ph.D., is an assistant professor within the Division of Forestry and Environmental Conservation at Clemson College. Twitter/Instagram/TikTok: @drdavecoyle. E mail: [email protected].
