Hello everyone, I several large weeds of the same type growing in my back yard in between my wire fence and my neighbors wooden fence. These are currently 7 feet tall, and I would love to know what they are. Thanks for your help!
I don't recognize it but it is one of the tallest weeds I have seen.... too bad it wasn't a sunflower
I think it might be Japanese knotweed. Found a pic of that and it resembles it. Yes, I wish it were a sunflower!
Has it ever bloomed? Pokeweed will have pinkish-white blooms followed by dark purple berries. Phytolacca americana (American Pokeweed ) or Polygonum cuspidatum - Japanese Knotweed leaves are heart shape and shorter than your plant. http://www.eattheweeds.com/japanese-knotweed-dreadable-edible/
Since it can't be dug from between those fences, pouring a pan of boiling water on it (after cutting off @ ground level) should kill the root. This is a native plant though, a source of food for birds, and looks like a good spot for one, if you want to keep it. It's definitely not knotweed.
This is not knotweed. It grows abundantly here and it does not look like this. Pokeweed? yes. You won't be able to dig it out if it is between two fences and you can't get in there. the root is a taproot and grows to the size of a mans arm or greater. I am not sure one dose of boiling water will kill it though. It may take several doses.
Horticultural Vinegar has a 20% acidity level and will work quicker and hit the roots better than household vinegar has been watered down to only 5% acidity strength.