Hemlock Wildlife Value

When I was working in PA several years back, there was talk among the foresters down there about using Norway spruce as a potential hemlock alternative because it establishes well, produces dense shade (a la hemlock) and is readily available from nurseries. The drawback of course is that Norway spruce is a non-native species (but then, I've seen others advocating for Chinese hemlock as an alternative too...).

I agree! I also would have picked white spruce and white pine. I'd also suggest the northern white cedar (aka arborvitae) because it can create dense shade conditions similar to that of hemlock. The hard pines (like red pine or scotch pine) can be OK but they let a lot more sun through than hemlock, and they usually like to have their feet dry meaning they might not do as well along streams. There's also red spruce, black spruce and balsam fir, but they'll only work for the select few properties that have high elevation or particularly cold valleys. But really its all a case-by case basis. Some organizations have been experimenting with the Chinese hemlock because it is extremely resistant to the wooly adelgid. It is not native, but it not known to be invasive, and it looks and behaves very similarly to our native hemlock. Unfortunately it is not easy to find at any nurseries around here. There are a few planted at the Siuslaw and Clearpool Model Forests and there are some at the Lasdon Park and Arboretum in Katonah, NY that are about 15 years old.

Norway would probably work well. Concerns I would have is that it likes better drainage than white spruce and can get very tall which may not be a problem for many sites. I think it does make it a bit more susceptible to windthrow.

The white spruce should work very well, though the fishermen may have trouble casting!

Yes, the Norway spruce is more susceptible to wind-throw than many of our native conifers. Its roots are shallow. But this weekend I was hiking at the Sundown Wild Forest in the Catskills (near Vernooy Falls) and came across a large area of hemlocks that had blown over. Perhaps they were already weakened from the HWA, but the other species fell over too. Once one goes, the others tend to follow!

I have seen Norway Spruce grow very well in wetlands or other poorly drained sites. In central New York (Cortland, Cayuga, and Chenango Counties) I've seen it reach up to 40 inches in diameter on such sites. But then I've seen it topple over. However it then sometimes releases once suppressed seedlings. It is certainly an impressive tree!

I feel it can't hurt to mention the Hemlock's value for Deer and other wildlife in winter providing cover as well as bedding areas, I have seen a combination of Norway spruce and Red spruce work well in filling that niche. Grouse seem to like that habitat as well, in my experience at least. The blow down at Vernooy Kill falls is certainly worth a visit! It is expansive and I believe a domino effect from of Hurricanes Irene and Sandy, I'm interested to keep and eye on what starts to establish in that area. It must have been quite the job to clear that trail.