Hemp field

Industrial hemp field. 

No, that’s not going to be marijuana planted at Penn State University’s research station in Rapho Township this summer.

Greg Roth, a professor of agronomy, said Penn State is seeking and expects to get permission to grow about 2 acres of industrial hemp on the Rapho Township site.

It will be the first time hemp has grown legally in Lancaster County since the plant was banned nationwide in 1937 because of its similarity to marijuana.

A program allowing hemp for research purposes started last year but had no local participants.

Here are some key things to know about the return.


Below 0.3 or no go

Marijuana and hemp are both types of cannabis and look similar; the key difference is level of THC, a compound that causes psychoactive effects.

By law, industrial hemp must test below 0.3 percent THC.

By contrast, the National Institute on Drug Abuse said marijuana samples confiscated in 2014 had average THC content of 6.1 percent, with the average marijuana extract containing more than 50 percent THC.

And research released in 2015 by a licensed Colorado lab found average THC levels of 18.7 percent in legal marijuana there.

The weed problem

As in literal weeds, not marijuana.

“No herbicides are registered for hemp in the United States,” said Roth. “You basically have to try to grow the hemp organically.”

He said the weed problem was the biggest takeaway from the program’s first year, and that growers are trying different varieties, planting dates and cultivating approaches to stay ahead of the interlopers.

Food, not feed

Penn State’s research is focusing on on hemp seed, which under state law can be used for food but not feed — that is, for humans but not animals, Roth said.

“Ironically, you can eat them but you can’t feed them to the birds,” he said.

The birds will probably eat them anyway; Roth noted that a flock of mourning doves haunted Penn State’s test field near University Park last year around harvest time.

But, he said, deer and groundhogs didn’t seem to be a problem.

Not so high

Varieties of hemp grown for fiber can grow as tall as 12 to 13 feet, Roth said, but the five Penn State plans to plant this year are for seed and range from about 3 to 5 feet high.

One reason, he said, is that in the absence of specialized equipment for hemp, they’re using standard combines — and hemp fibers can wrap around internal parts of the machines, causing problems.

So, he said, the shorter varieties are easier to harvest.

Calling the cops

One requirement of the program, Roth said, is notifying state and local police of where the hemp will be planted.

The hemp will be planted in open fields like any other crop, he said, but will go on part of the research plot that’s away from the road.

He also noted that restrictions make getting seeds a tedious process; Penn State had to go through the Pennsylvania Department of Agriculture to purchase them from Canada.

By the numbers

Last year Penn State harvested its hemp about 90 days after planting it, Roth said, and had yields of about 1,500 pounds of seed per acre.

“One of the advantages of hemp is it could be grown after another crop, like barley or wheat,” he said.

This year planting will be staggered from late May through mid-June, he said.

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