“They said…” Lessons learned in the 2019 hemp harvest – Peter Hughes, Red Barn Consulting Inc.

Posted on March 11, 2020 in Forage Foundations
Click here for Hughes’ PowerPoint presentation.

After the 2018 Farm Bill passed, hemp officially came off the federally banned narcotics list, where it had been since World War II.  Since then, Peter Hughes said it has been “like a goldrush” to go out and plant hemp, however, most people didn’t have a plan.

“Unless you have a supply chain, it has been really hard to sell and make money,” said Hughes, owner of Red Barn Consulting Inc., an agricultural and consulting firm based in Pennsylvania.

During his breakout session at the 2020 Vita Plus Custom Harvester Meeting, Hughes explained the basics of growing hemp and how it can be harvested mechanically.

The basics
Hemp and marijuana are cousins, and Hughes explained the only way to tell the difference between the two is with a test for tetrahydrocannabinol (THC), the psychoactive compound common in marijuana.  Over the last two years, most of the interest in growing hemp has been driven by the cannabidiol (CBD) market.  CBD is a chemical compound present in both hemp and marijuana with unregulated health claims that is legal to consume, unlike THC.

Hughes explained hemp seeds for CBD must be female and hand-planted.  Growers can either purchase feminized seed, feminize their own seed or purchase clones.  If male seeds are planted, they will pollinate the female plants and dilute CBD levels.

“In my opinion, fiber and grain/seed are the future of hemp,” Hughes said.

He sees hemp for fiber taking off in the next four to five years because both male and female plants can be used.  He said he also believes hemp for CBD will eventually be grown in greenhouses to prevent pollution.

Traditionally, harvesting hemp for CBD is very labor intensive.  It is usually harvested by hand and manually hung up to dry.  When Hughes first started harvesting hemp mechanically, he said they learned more from what they did wrong than right, but they have found ways to mechanically harvest it successfully.

One solution was with a 15-foot draper head designed to cut tough, fibrous crops, while gently handling the plant to load it onto a conveyor belt and into a wagon at a rate of seven to 10 acres per hour.  Hughes said this worked well, but they didn’t think about how they would be limited by the infrastructure around them and by how fast the plants could be hung, which is where the labor goes.

Hughes explained the plant is harvested at 85% moisture, but CBD extraction labs want it at 10% moisture.  While mechanical drying exists, it is more economical and efficient to use and adapt existing infrastructure, such as tobacco barns, tunnels, or greenhouses, for this industry, although those spaces are limited.  Additionally, if the plant heats above 105 degrees F, you risk degrading the CBD content.

“We still need to figure out how to dry on a macroscale,” Hughes said.

Hughes has also successfully used a chopper to harvest hemp.  He said you can chop the entire plant and use a high-capacity forage baler to bale the product.  While it may ferment a little, it ultimately spaces out the drying time and doesn’t alter CBD levels unless it heats.

Lastly, Hughes spoke about using a combine to harvest hemp.  Hughes said a conventional combine with a beater head works to remove the flower from the stalk.  He also made modifications to his John Deere 9600 that will strip the buds from the dried plant.

Hughes said mechanically harvesting hemp requires a lot of cleaning and maintenance as the machinery can plug quickly with the sticky plant, but the efficiency is worth it.

“You lose about 1% of the CBD through the combine, but the savings in labor pays off,” Hughes said.

Category: Crop varieties
Forage Foundations
Forage harvesting