Tyson adds a much appreciated nuanced response. I agree that ecological context should be taken into account whenever possible, as well as with his point about looking at the whole carbon footprint of a planting project. I am unfamiliar with the ecological context of South-Central Iowa:I was answering generally without looking at the specific question. So first generally:
Planting trees which were grown nearby not only lower the carbon balance of the project (through reducing transportation costs), but also lower the chance of pests being spread (which often happens through the movement of nursery stock). Furthermore, planting trees grown in local nurseries makes it more likely that the trees are already adjusted to the local climatic conditions. I agree that trees should be planted in the context of the area: not only will this make their success more likely, but can help boost populations of native trees. Both age diversity and genetic variation are an important component of a healthy forest, but may be difficult to accomplish. Age diversity requires long term planning. In Durham, NC we are currently experiencing the result of a lack of this planning: the city is filled with beautiful willow oaks, who have reached their age limit and are now dying more or less all at once. My impression is that within species genetic diversity is hard to accomplish when utilizing nursery stock. Thoughts? Now, as to specifically planting trees in South-Central Iowa. Often we move without looking at the larger affects on the ecosystem. What happens if the trees planted escape and take over? Are we planting trees easily controlled, or does it matter? In the Carolinas we have problems with escaped china berry and bradford pear and are beginning to see the escape of lacebark elm. However, in the face of the dramatic loss of forests across the midwest due to the beetles, maybe we should be actively creating forests in other locations. Or should we working to maintain the ecosystems around us how currently are, remembering that they are as much as a verb as a noun? Perhaps this is too big of a question for this thread, but I am curious to hear what those with more experience than I think. On Sun, Feb 26, 2012 at 9:39 PM, Wayne Tyson <[email protected]> wrote: > Ecolog: > > [Note: I, for one, like this way of responding to initial posts, with the > original subject-line and the string of subsequent comments preserved, rather > than individual responses to the initial post. I know it is not possible for > this to remain uniform, because some will post before one or more other > responses are posted, (ships will pass in the night) but it is nice to have > the thread in a sequence. I also appreciate it a lot when tangential posts > preserve the original subject line whilst adding an appropriate subject label > ahead of the initial one so that I, the reader, can follow all of the > branches of all the tangents back to their source.] > > I share Rose's comment about the Hernandez post, which I agree is "right on." > > I am not opposed to Rose's comments, but they do strike some complex chords > for me. > > Rose is right on when she mentions resilience, and I would add that not only > diversity in species is important, but diversity of age classes and genetic > variation also is important--yea, more important than species diversity in > some contexts. One thing troubles me a bit however. Well, maybe it troubles > me a lot. > > The implication of Rose's and Johnson's remarks seems to be that one can > decide to plant all kinds of different species without regard to the > suitability of the site for the species, although they perhaps believe that > such goes without saying. In my days in the U.S. Forest Service, for example, > we were careful, perhaps absurdly so, about the provenance of the seeds > collected, taking care to note the elevation, orientation, slope aspect, etc. > so that the resulting saplings could be planted in comparable circumstances, > believing that a good match of the genes to the site would maximize the > potential for survival (e.g., temperature tolerance range, etc.) and result > in optimum growth potential. I know that forest science has undoubtedly come > a long way since then, so I look forward to those more advanced to bring me > up to date. > > But what disturbs me even more is the unstated possibility that various > sorcerer's apprentices might loose designer-trees based upon some marginal, > perhaps largely fictional, increased ability to provide a single "ecosystem > service." (For some reason the Irish potato famine comes to mind . . .) > > The request also strikes me as more horticultural than ecological, and Rose > and Johnson seem to imply that planting trees in South-Central Iowa (or any > other location) can be done without regard to ecological context. While all > the things Rose mentions are "good," and can be part of the ecological > context, I often hear/read/see similar tree boosterism overriding ecosystem > concerns as well-intentioned prescriptions without regard to context. > > Also (almost?) never mentioned are the supposedly tangential but real factors > in the net-energy and carbon-balance equations that include energy > consumption and carbon-release numbers associated with the production, > transportation, and planting of growing trees. I stand ready to be further > enlightened on this subject as well. > > WT > > ----- Original Message ----- > From: "Katie Rose" <[email protected]> > To: <[email protected]> > Sent: Sunday, February 26, 2012 4:14 PM > Subject: Re: [ECOLOG-L] best tree species for carbon sequestration > > > Hello Dr. Johnson, > > I'd like to supplement some of the points made by Jason Hernandez, > which are all right on. > > The best way to promote carbon sequestration is to plant a resilient > forest: one that has a combination of tree species so you are buffered > against pests and diseases, and then plan for what you will do with > the trees after they die. If you plant trees which can be used to > create furniture, such as cherry, oaks or pines, you will be creating > a more permanent carbon sink. Also you can direct dead trees to a > facility which will burn them for fuel: this will not only produce > "carbon neutral" power, but will prevent more fossil fuels from being > used. Finally, you can compost tree matter (leaves, pruned branches, > etc). Although much of the carbon will be released, some will remain > in the soil, which is actually a very under appreciated "carbon sink". > > An aside: besides providing for carbon storage, trees help cities in a > huge variety of ways. They improve urban streams by intercepting storm > water (prevent flooding), stabilizing and creating soil, contributing > organic matter, and cooling stream water. Trees cool streets and > buildings, reducing air conditioning costs (and therefor lessening the > electricity needed to climate control the building). They remove > pollutants from the air, and provide habitats for birds, bugs, > squirrels, and other wildlife. > > > > Katie Rose > > > > > > On Sun, Feb 26, 2012 at 11:52 AM, Jason Hernandez > <[email protected]> wrote: >> Your criteria are shared by countless homeowners wanting to landscape their >> yards (fast growing, long-lived, low maintenance). Unfortunately, there are >> physiological tradeoffs involved, whereby fast growing trees tend to "live >> fast" in other ways, too, and hence are as a general rule not long-lived. >> Think about the way forest succession works: fast growing trees fill in gaps >> quickly, reproducing before the competition catches up; slow growing trees >> are the shade tolerant ones, coming up underneath the fast growing pioneers >> and eventually supplanting them. >> >> >> From what I have read of carbon sequestration (as it is not my primary area >> of knowledge), old-growth forests hold a lot of carbon, but do not take it >> up quickly; the decomposition of old trees and the carbon uptake of growing >> trees about cancel out, making the old-growth forest approximately >> carbon-neutral. Young forests take up carbon quickly, but as they age, the >> uptake rate slows down. When a tree decomposes, all the carbon sequestered >> in its biomass is re-released. So to have effective sequestration, you would >> have to have a steady supply of young trees taking up carbon, without a >> concurrent stream of decomposing trees. Net growth would have to exceed net >> decomposition. In other words, the only long-term way to counteract >> ever-increasing CO2 emissions, is to have ever-increasing acreage of forest. >> >> Jason Hernandez >> >> >> ________________________________ >> >> Date: Sat, 25 Feb 2012 11:59:02 -0800 >> From: Stephen Johnson <[email protected]> >> Subject: best tree species for carbon sequestration >> >> dear Ecolog-ers, >> >> I am designing a tree planting-planting project designed to counter CO2 >> production at a college in south central Iowa. Students will be involved in >> planting. I have heard that Tulip tree (Liriodendron tulipifera) and >> sweetgum (Liquidambar styraciflua) are both good candidates for carbon >> sequestration an I wonder if there is any primary literature that backs the >> claim. Also are there any other tree species with high rates of carbon >> uptake and biomass accumulation, fast growing and long-lived and with low >> maintenance and perhaps with any or all of these properties reflected in any >> scientific studies. >> >> Dr. Stephen R. Johnson >> Freelance Plant Ecologist/Botanist >> [email protected] > > > > -- > Katie Rose Levin > Duke University, Nicholas School of The Environment > Masters of Environmental Management Candidate, 2012 > Masters of Forestry Candidate, 2012 > > Environmental Professional, National and North Carolina Association of > Environmental Professionals > Wilderness First Responder, National Outdoors Leadership School > > > The true meaning of life is to plant trees, under whose shade you do > not expect to sit. ~Nelson Henderson > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 10.0.1424 / Virus Database: 2113/4833 - Release Date: 02/26/12 -- Katie Rose Levin Duke University, Nicholas School of The Environment Masters of Environmental Management Candidate, 2012 Masters of Forestry Candidate, 2012 Environmental Professional, National and North Carolina Association of Environmental Professionals Wilderness First Responder, National Outdoors Leadership School The true meaning of life is to plant trees, under whose shade you do not expect to sit. ~Nelson Henderson
