Forest Tree Regeneration Considerations: How Do Concepts of Ecological Integrity and Climate Resilience Fit?

Burn severity map of Hayman Fire

 

Jon and I got into one of our usual discussions about NRV and what it means in the comments here, related to the MOG- NPR.  What I thought might be useful and fun is to take two topics we know something about … reforestation and stocking level.. and look at them through different lenses, specifically those of climate resilience compared to ecosystem integrity and see if they’re the same or different, and how they might be applied. There’s also the question of what exactly is the role of the Forest Plan.  Is it relevant? How should it be relevant?

I think we concrete and abstract people can easily talk past each other, as in this 2010 post, so here is a specific example and I’m hoping that we can illustrate how the answers might be different if we were operating under “climate resilience” versus “ecosystem integrity” or NRV as a goal; or not.  If they are identical concepts the FS has it easy, if they are different, we need to talk about how and why.

Example:Replanting, What, Where and How Much-The Grandiose Fire

Your district recently had a large fire, the Grandiose Fire.  You are assigned to help determine if replanting is needed, and where and what species, and planting density.  For this example, imagine your own local area where you understand the species mix and characteristics.

I’d start with the biology and reproductive characteristics of the trees that were growing/continuing to grow there.

First, I’d  look for areas where natural regeneration is going to have a tough go.   Suppose places are, say, more than a mile from living, seed-producing trees. I’d also look at the topography and soils and location by water that influence which species tend to grow where.  I’d want to make sure that the rarer species are still represented in their current topo/soils niche. In this area, ponderosa is common and Doug-fir and spruce also occur in spots.  From what’s left in less intense areas you can get an idea of what was growing there. In more intense areas, you might remember or have records.

In other areas, with remnant seed producers (or serotinous cones for LPP), lodgepole and true fir may come in on their own and ponderosa may need interventions (planting) to become established. Or grass or brush competitors may come, in such that if you don’t plant right away a window is lost. How long does that take?

What do you know about natural regeneration? What about seedling survival? What about diseases? Browsing? Insects? Porcupines? How much work can yo do? How much money do you have? Do you have seed? Do the nurseries have capacity?

Check out what the Coconino has been doing to keep natural aspen regeneration alive. Tree regeneration, in many dry places,  is not a job for the easily discouraged nor the faint of heart

In many dry places, it can be a tough life for planted seedlings.  If you’re in a situation where the only stocking will come from planted trees, do you overplant, to increase the likelihood that some will live? But then you might have to come back and thin to desired stocking, which costs money.

When I think about all these considerations, and then I think of climate resilience, I tend to think more along a generic scenario “what if it gets hotter and drier?”  Probably  in our area, you would want low density of trees in case of drought.. but you are still working in the window of “some, but not too many,” with many survival unknowns.

It might also be more important to get more dry-loving and fire-resistant species in the mix, so plant pine where it isn’t coming back (maybe some proportion more than you would have otherwise?).

When I think about this real world question (plant/not plant, how many, what species, where), it seems it’s fairly easy to consider climate resilience. Are integrity and NRV covered simply by trying to get the same species back? Or it is more complicated?

And for those of you currently working in forest regeneration, tell us your thoughts and experiences.

10 thoughts on “Forest Tree Regeneration Considerations: How Do Concepts of Ecological Integrity and Climate Resilience Fit?”

  1. See Section 4 of the NFMA: “(d)(1) It is the policy of the Congress that all forested lands in the National Forest System shall be
    maintained in appropriate forest cover with species of trees, degree of stocking, rate of growth, and
    conditions of stand designed to secure the maximum benefits of multiple use sustained yield management in
    accordance with land management plans.

    Reply
    • Thanks, A! I actually had pulled out that quote but the post was too long so I cut it. I also thought the ideas therein about rate of growth would equally apply to carbon. plus ça change and all that.

      Reply
      • Post-fire reforestation is very different from post-harvest reforestation. Many places are burning that would not have been harvested due to regeneration difficulty or land management objectives that were not consistent with timber harvest. That makes reforestation (both natural and planted/seeded) more challenging on some sites – it requires more thinking….and there is no one size fits all.

        Reply
        • My point was simply that there are so many other variables, and difficulties involved that it isn’t clear to me whether the NRV/HRV/ climate modeling discussion is all that relevant.

          Reply
  2. I like what you both are saying; when I was doing reforestation in the Northwest, steep, marginal areas that had burned actually changed land class designation from “standard, or marginal” to non-forest. Hell of a time to change in the Forest database, but that was the correct outcome. Planting is costly enough to begin with without throwing good effort away.

    Contrast that to the South, where you can almost throw seedlings out the truck window, while driving down the road and get a stand! It takes experience to recognize the virtues of a strong knowledge base and actually be successful in regenerating forests. I have my doubts this new initiative will exude fruition….. but we can hope!

    Reply
  3. After the fire, you look at the forest plan. Forest plans should answer the question of what the desired condition of the land is. This should be expressed in terms that describe species, age distribution, pattern and density. (Forest plans typically do the first two and maybe the third, but I’d like to see an example of desired density.) That information should the be basis of a prescription for reforestation (and for prioritizing which areas to reforest based on the likelihood of achieving the desired condition without it).

    “Are integrity and NRV covered simply by trying to get the same species back? Or it is more complicated?” Integrity and NRV are “informed” by what used to grow there. They should “be” what is expected to grow there. I don’t know whether that takes “climate modeling” or just a generic scenario “what if it gets hotter and drier?” It does require the best available science. It’s quite possible that the logic you have laid out would be the best way to answer the implementation questions and achieve the desired condition.

    Reply
    • Well, it’s kind of funny I just had a flashback to pre 2012 Rule and discussing desired conditions with DeAnn Zwight, then Planning AD…

      how exactly do you come up with desired species, age distribution, pattern and density?

      Our discussion went something like this…
      me: “how do you come up with x% of the Forest should be in LPP ages 10-20, y%. 20-30 and so on?” I couldn’t figure out a way other than HRV (like I said we didn’t have NRV because it was before the 2012 Rule).

      Reply
  4. NRV generally only deals with stand structure stage/successional class – yet the NFMA refers to consideration of much more than that – some places have developed an NRV for species composition and density. Structure NRV also reflects a modelled average and doesn’t really reflect the tails of the distribution in terms of the proportion of the landscape in each structure stage, so when you are dealing with a very large disturbance NRV based on structure stage may not be very helpful.

    Reply
      • I think this document was used in the development of the 2012 Planning Rule (it’s from 2009): https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/fsbdev7_020892.pdf

        Regarding climate change (HRV—>NRV): “Improving ecosystems models may take decades before realistic landscape simulations can be used to account for climate change in species and landscape response. In the meantime, it is doubtful that the use of HRV to guide management efforts will result in inappropriate activities considering the large genetic variation in most species (Rehfeldt et al., 1999; Davis et al., 2005) and the robustness inherent in regional landscapes that display the broad range of conditions inherent in HRV projections.”

        HRV/NRV is supposed to be determined by a forest during the assessment for plan revision. (I couldn’t find it in the Nantahala-Pisgah assessment, so I’m wondering how they can talk about ecological integrity.) What I recall in practice (mostly from the Interior Columbia Basin Project in the 90s) is the use of simulation models run essentially backwards many times to produce probable historic conditions over time. I have also seen the concept applied to landscape distribution of watershed conditions over time.

        Reply

Leave a Comment