Should I worry about planting nonnative Norway spruce in NY?

Question

I'm looking for the perfect tree to create a low maintenance living privacy hedge/windbreak in an approximately 100'x100' area. About 20' from one part of the area, water pools sporadically. I'm eyeing Norway spruce, White spruce, and White pine. I'd prefer a native species to NY, but White pine doesn't seem to have the wind resistance I'm looking for or density necessary for a privacy screen. I was thinking White spruce, but Norway seems to possibly have better wind resistance, combined with faster growth and a broader mature spread so I won't have to spend as much on tree seedlings. Wind resistance is important because these trees, though entirely on our property, will be within fifty feet of a neighbor's house and would fall her way due to prevailing wind.

I'm worried if I plant Norway spruce, which is native to Europe, the tree may eventually become invasive in the local environment. Is this a legitimate concern with Norway spruce, or a nonissue? Any other advice for the privacy screen/windbreak welcome.

Answer 1

I grew up with a Norway Spruce in my front yard, planted by my grandfather in the early 1940s. It's still there today - pretty tall (maybe 60-70 feet) and way too wide for a 35 foot wide lot. For probably that reason, Norway Spruces are my favorite type of spruce.

I think they'd be a good choice for your windbreak. This site has nice write-ups on a variety of evergreen trees that could be used for windbreaks, and they love this tree. As for invasiveness, my own experience in Wisconsin is that it is not invasive in this state (note that this is anecdotal). There are three large Norway Spruces in the park across the street from my house and I've never found a seedling. There's a single yew behind my house and I have seedlings everywhere. I also have some arbs on my own lot and elsewhere and their seeds are also everywhere. Same with Juniperus virginiana (a native). So - I would say invasiveness is not a problem here.

OTOH, this ten-year-old site does indicate that it can be invasive in New England, but that it is NOT on the invasive species list at that time. Note that it gets the height of the tree incorrect, so take it with a grain of salt? A quick tour of the internet found no other sites that consider this tree to be invasive. Dr. Michael Dirr, expert on woody plants of North America, does not mention invasiveness as a problem—he does consider some of the cultivars to be so ugly that they'll scare the deer, though :)

Note - Norway Spruce is not on New York's invasive species list.

Important note - like other spruces (and pines), Norway Spruce is susceptible to Rhizosphaera needle cast disease, but it's resistant than most spruce. This web site from UMass is probably the most relevant that I could find in your area about this disease. The Universities of Wisconsin and Minnesota, and Iowa State University also have excellent information about this disease, if you're interested.

Answer 2

In Michigan, it’s considered naturalized and non-invasive, of high ecological value, and integral as food supply and shelter for several species of birds and mammals. Although it’s shade tolerant, it will be suppressed under low light or as an understory tree. It’s slower growing and doesn’t reproduce in the first 30-40 years.

Norway spruce form a forest biome similar to eastern hemlock, unique from other conifer biomes, and hence the considered a key species in mitigating the decline of the hemlock.

Cited sources online are missing or don’t list or state it’s invasive. The National Invasive Species List does not list it as invasive, nor does the West Virginia DNR on its 2014 invasive species report nor current web pages, making the PLANTS database inaccurate.

Answer 3

It is indeed considered invasive due to its shade tolerance when young but dense shade producing habit when mature. The cat is probably out of the bag on this one though - it's the most widely cultivated spruce species in North America, according to this source.

FTFA:

It is mostly green mosses that can survive in the environment of well developed Norway spruce stands. These are typical northern conifer forest (taiga) dominants--same exact species that dominate Canadian as well as north European conifer forests, for example, Hylocomium splendens or Pleurozium schreberi. No tree from Massachusetts known to us can share dominance with Norway spruce: the spruce appears to always form single-species stands.

Answer 4

It is labeled "Invasive" however given it's slow growth rate it's not that big a ddeal. The problem is when it first deposits seeds they have the potential to spread because they're shade tolerant growing slowly but strongly. Native species include "White Spruce" (Picea Glauca) "Eastern Red Cedar"