Back in Washington State I would occasionally be riding along on my bike when I would smell a particular fragrant plant then have the overwhelming urge to head to a mirco-brewery. The plant that would cause such an urge was Humulus lupulus, or Common Hops. I knew the odor well as we had a Centennial Hops growing in our back yard in Sequim.
Back in the spring I began to see a plant growing on the side of the road that looked very much like hops, but the fragrant smell was absent. I stopped and crushed the leaves to see if it had the distinctive odor and it did, but very faintly, clearly not the hops that I was familiar with back in Sequim. I took a chunk of it home and as it turns out, it was a species of hops, Humulus japonicus, or Japanese Hops.
As the summer has worn on here I have seen more, and more, and more of this stuff creeping along the roadways of southeastern PA. In fact, once I began to hone in on it, I’d notice it taking over whole fields! Instead of invoking pleasant thoughts of heading to a brewery, I began to have nightmare that if I stopped to long on the side of the road I would be swallowed whole by a killer plant. It reminds me of that other invasive vine from Asia – kudzu.
One of the things about the Northeast that I have always liked is that the winters here seem to be to cold for kudzu to thrive like it does down south, but where kudzu leaves off, Japanese hops seems to take over. One thing that is a little reassuring is that Japanese hops dies back completely in the winter, so its ability to cover entire forest is somewhat limited.
According to the USDA there is not much that can be done to control Japanese hops. The best method that I can find is mechanical control which, in the long run, does little to stop its spread.
As a side note, it is one of five members of the Hemp family found in Pennsylvania. According to the Plants of Pennsylvania common hopes and its more infamous cousin marijuana are also found growing wild in the state but in a very limited number of places. The two other members of the family are native. Hackberry (Celtis accidentalis) is found commonly throughout the state and dwarf hackberry (Celtis tenuifolia) is limited to the southeast and southcentral regions.
See more photos of the best here.
Ride lots, stop often,