Lee, et. al., I would love to see one of these "rhizotrons". Fascinating.
I have questions if anyone can help me out: 1. Are mycorrizae absolutely essential for young tree roots to grow and do trees have mycorrizae associations throughout their lives? 2. I'm confused about the exact relationship between the bacteria in the soil that fix nitrogen and the tree root itself. I know this is a broad and vague question....just wondering it those bacteria are considered part of the tree organism? Thanks, Jenny On Mar 12, 8:54 am, Lee Frelich <[email protected]> wrote: > Ed et al.: > > We usually measure root biomass by taking soil cores (usually 2-4 inches > in dimeter, from 1-3 feet deep, depending on the purpose of the study), > and separating the roots so they can be dried and weighed. By taking a > number of such samples, we can estimate the biomass of roots per acre in > the forest. Roots are also studied in rhizotrons (underground rooms with > large windows all around). One can observe the root growth against the > windows, study how earthworms move, and how the soil zonation changes > over time, etc. The University of Michigan Biological Station and > Michigan Tech have rhizotrons that I have visited. There are also mini > rhizotrons that can be placed throughout the forest. > > Of course, these do not give you an estimate of the roots of one tree. > I have seen that done by blasting away the soil with high pressure > hoses, so that the root system can be mapped and measured. This is done > in a stand that is planned to be clearcut, or perhaps a few trees in an > experimental forest, and it only works in ecosystems with shallow soils > and/or rooting depths. > > Lee > > Edward Frank wrote: > > Jenny > > > I am sure if there was some practical and non-destructive method of > > measuring the roots underground, we would give it a try. Ground Penetrating > > Radar is still a little expensive at the moment. > > > Ed > > ----- Original Message ----- > > From: "Jennynyc" <[email protected]> > > To: "ENTSTrees" <[email protected]> > > Sent: Wednesday, March 11, 2009 8:06 PM > > Subject: [ENTS] Re: Roots? > > > Russ, > > > Thanks for letting me know about this. > > > Jenny > > > On Mar 11, 2:27 pm, [email protected] wrote: > > >> Jen: > > >> No. That type of work is usually done by researchers looking for a > >> specific > >> piece of information about a tree or group of trees. > > >> Russ > >> **************Need a job? Find employment help in your area. > >> (http://yellowpages.aol.com/search?query=employment_agencies&ncid=emlc...) --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
