Eeeuch. :( Japanese Knotweed is evil, evil stuff. It's the only organic material from the yard I put right into the trash bin, instead of composting. Three years of regularly weeding the infestation here have slowed it down slightly, but not much. In your situation Queuetue, I'd be tempted to go through the compost carefully and remove all the Japanese Knotweed you can find -- especially the roots -- and then set the remaining compost aside for a year. Maybe even inside sealed plastic garbage bags, to help anaerobic conditions occur which might help kill and break down any remaining knotweed roots or stems. Or, you could just spread the possibly-contaminated compost as a surface mulch on garden areas which already have knotweed, then watch those areas closely. In the part of the garden here which has knotweed, I don't ever till any more, or even rake the soil. Each year the new sprouts come up slower and fewer, but they still come up. One time last summer when I'd neglected weeding for two weeks, there were fifty of them. And in the summer of 2005, before I found out what kind of plant it was, a single stem grew over my head -- in one month. Good luck Queuetue and all the best, -Patrick Here is a link that might be useful: Wikipedia article on the evil weed

Do you need privacy year round, or really just in warmer weather? This question is important since it decides whether you are limited to just evergreen plants. You'll still hear cars with plants; only walls or earth berms will really block sound. If you plant some along the margin of your yard and some along the road, you shoud be able to achieve pretty good visual privacy. Regardless of what you plant, for the first year plan on mulching around the each plant a couple feet out as well as watering them any time you aren't getting regular rain during the growing season. Is it really 100% shade all day or is there some sun at the beginning or the end of the day? What side of your house faces north in the photo? The quality of the shade will effect how densely plants grow. The list below are plants that will grow in part shade or high shade, though not densely, in my experience. Check out clethra alnifolia, any of the shrubby dogwoods like the red-twigged dogwoods, or native viburnums (nannyberry, arrowwood, wild raisin, highbush cranberry), many of which may be available inexpensively from your local conservation service, though if not I've provided a link below to the NH state forest nursery which will ship orders in spring. These will be small and may do better if you grow them in a nursery bed or large pot for a year before planting them out. Many of the more common rhododendrons like R. roseum elegans, Olga Mezitt, and PJM can be bought from big box stores in spring and fall in quart or 2 quart pots, and if you are lucky quite inexpensively. I bought some Olga M and PJM a couple of years ago for $8 per pot and when planted 5 feet apart they will grow together. They may not bloom too well in that much shade, but they should grow and are evergreen. If you are willing to do some propagation yourself, old-fashioned forsythia grows pretty thick and twiggy enough to provide some privacy even in winter. They root and grow fairly easily from cuttings and then grow fairly quickly. If you peg down the lower branches of the rhodies, they will root and then can be transplanted in a year or two. Some needled evergreens may grow there. We have balsam fir growing in part shade in the woods, though I am not sure if you are too warm for it. White pine may grow for you there, though it won't stay at a height to block cars after about 20 years and won't be super thick growing in shade. Regardless, start working to get rid of the knotweed now, disposing of the seeds in a trash bag, not as compost. Either cut them down constantly or apply frequent coats of herbicide whenever you see leaves so that this doesn't get out of control. Here is a link that might be useful: NH State forest nursery

Yes, it is one of the large, perennial knot-weeds. However the leaf shapes visible here are like those of Bohemian knot-weed, the hybrid between giant and Japanese knot-weeds that is often mistakenly called Japanese knot-weed.

It's knotweed. In addition to the fact that it's obviously not bamboo, another giveaway is that you would not be able to "have pulled some out" if it were a real bamboo. Also, be aware that, unlike bamboo, knotweed can regenerate from small root fragments, so dig it up and make sure you remove all pieces from the ground.