Here's the picture: 36" dia sugar maple (Acer saccharum), euonymous vines growing up trunk and major leaders, English ivy growing on the surrounding ground. About 4' from the tree runk the owner has positioned an oak 1/2 whiskey barrel filled with soil. It's been there about 15 years. Each year it's been planted with annuals (e.g. geraniums, impatiens) and kep well watered and dosed with soluble fertilizers. Last few years it's been very difficult to do the planting.

The soil in the barrel became a dense, fibrous mass of woody roots. The barrel was held to the ground by them, couldn't even overturn the barrel to clean the mess out. With a little wrestling the old barrel fell apart revealing the contents. A few of the roots were up to 3/4" the rest were fibrous.

Given the surface appearance of the larger ones and the minimal distance from the maple trunk, I'm 95% sure they are not maple roots. Did not have time to physically trace any to source.

It brings up an old question of mine: is there any such thing as a root key? Are there sufficient differences in root tip morphology, root bark, root tissue that they are keyable?

The case at hand is a curiosity. But a root key would be a useful to help decide, say "are these roots are from tree X which is going to be saved or tree Y which is going to be removed?" when establishing tree protection zones.

Reply to post by Scott Cullen, on May 02, 1999 at 07:04:17:

Scott, I don't know of any published root keys, but there may be one somewhere. I have started a small collection of root studies of my own. I'd be interested in taking a look at this, if you care to send down a small piece. A chunk of the largest piece available, with some smaller roots, would be fine. Might be able to make an ID for you.

Reply to post by Russ Carlson, on May 02, 1999 at 07:04:17:

This is some distance away, but maybe.....

Reply to post by tubs, on May 02, 1999 at 20:59:03:

Interesting! But that's basically what I do- compare known and unknown.

Soon as my budget allows some more updated equipment, I hope to start a database of slides to compare to.

Reply to post by Russ Carlson, on May 02, 1999 at 07:04:17:

Samples of unknown and two control species will arrive today. Thanks.

Reply to post by Russ Carlson, on May 02, 1999 at 22:46:05:


Russ,

Why not Photograph them. We you get enough you can write the
book. I would be happy to send you pics.

Mark

Reply to post by Russ Carlson, on May 02, 1999 at 22:46:05:

Same job, different day. Excavation on another part of site. Discovered remains of a quite rotted root about 2" dia. Given depth and proximity to foundation I'd guess it's from a tree removed for the structure, early '60s. From 5' away you could see the ray tissue where a shovel had sliced a cross section. was it oak?

Point is, I guess you'd have some photos at 1:1 or 1:2 close up, some at medium magnification (macroscope) and maybe some at higher magnifications (microscope).

Intuitively, I'd guess that gross features like rays will be less frequent than cellular differences that require greater magnification.

Reply to post by Scott, on May 03, 1999 at 21:58:20:

I keep forgetting that this is not e-mail ant that cetrain characters won't appear. That was supposed to read "..gee, is it oak?"

Reply to post by Mark Hartley, on May 03, 1999 at 21:58:20:

I plan to photograph many, as time allows. My macro equipment is not really up to par, though, so I would need to upgrade some equipment first to get print-quality photos. What I have now is OK for my use, but the lenses are not really sharp, and contrast is sh....., well, not very good.

Maybe I need to submit to the Research Trust for a grant. [g]

Reply to post by Scott, on May 03, 1999 at 21:58:20:

I was surprised a few years ago to find buried roots that were probably 3 decades old, still intact about 5 to 8 feet deep. The dense, thick rays clearly identified them as oak.

Root macro morphology often follws similar paterns as the trunk wood, since it is derived from the same genetic code. But there are differences that make it tougher to be sure. Getting good micro slides, on a limited budget is not easy, and very time consuming. Not really sure I want to pursue writing a book on the topic. Maybe if it hasn't been done when I retire. [g]

Reply to post by Russ Carlson, on May 04, 1999 at 06:34:47:

You may recall in Newport we discussed that in 1:1, 1:2 and 2:1 work depth of field is very shallow and the lense must be moved in a plane perpendicular to the surface of the subject or the edges go out. I had rigged a device to mount on the tripod for this but haven't done this stuff in years and offerred to lend it to you. It's been in the back seat of the car ever since and I keep neglecting to package it for mailing. This jogged my memory. SOON.

Reply to post by Scott, on May 04, 1999 at 21:02:24:

In the early 1980s, I took a course in close-upn photography, where I learned some neat tricks for this work. Depth of field is critical. Stopping down to small aperatures helps, but requires tremendous light. I have charts for all my lens assemblies on magnifications, distances & depth of field, and flash output needed. But holding a crawling bug still is quite a feat.

One of my best pics is a gypsy moth larva emerging from an egg- and filling the frame. Kewl!

Reply to post by Russ Carlson, on May 02, 1999 at 07:04:17:

The idea of a root key has been established for several years at kew Gardens in England. David Cutler is the contact person I think. They have been working on the root key to provide the information being discussed in this thread.

julian

Reply to post by Julian Dunster, on May 02, 1999 at 20:59:03:

Do you have an email address for DAvid Cutler?

Reply to post by Russ Carlson, on May 07, 1999 at 15:25:08:

I remembered they have a search engine for their system.

Reply to post by Russ Carlson, on May 07, 1999 at 15:25:08:

I remembered they have a search engine for their system.


http://www.rbgkew.org.uk/kewscientist/ks_oct94/africa.html

Reply to post by Russ Carlson, on May 05, 1999 at 05:18:04:


Hi Scott,

The freezer is the best tecnique for insects. It slows them
right down.

As for the photographs, look for a second hand bellows set or
use a disection microscope with Planapo lenses. Either will give you
good shots.

If you use black and white then you can adjust contrast easier and
don't forget to use tungstan film if you are using the microscope.

Mark

Reply to post by Scott Cullen, on May 02, 1999 at 07:04:17:

Crawling around in the crawl space (isn't that why they call them that?) under part of the house tracing electric wires. This excavation was done in 1961. This part of the crawl space is very dry. Found a cut piece of root about 3/4" dia. & 12" long with some finer roots attached. (Seems to me there were large Ilex in this area and an Acer rubrum nearby before the addition, but that's not the point).

The point is, this root was perfectly preserved. Except for being dry it might as well have been cut last week as 38 years ago. So it occurs to me that archaeologists have long used pollen analysis as a dating technique:
"OK, there are tree pollen grains here and we know from other evidence that the area was deforested 3,000 years ago so the level we're examining must pre-date that." I wonder if roots have also been used in dating? If the archeaology literature is another source for root key material?

Reply to post by Scott, on May 02, 1999 at 07:04:17:

As a matter of fact tree roots ARE used in archeology. I seem to recall that the digs at Pompeii used tree root analysis to determine what plants the unfortunate victims had been growing. I'd imagine that the archeological report would outline the protocols used, if you can find it. I believe that there are other projects have used similar methods. There is probabaly a whole career opportunity in forensic root analysis for the right person.

Reply to post by Scott, on May 02, 1999 at 07:04:17:

I posted on the Dendrochronology listserve, but no one there knows of a root key. I'll ask if they use roots for dating. I suspect they will say only for carbon dating, etc.

Reply to post by Russ Carlson, on May 13, 1999 at 07:15:05:

If there is archeaology literature it may not be confined to the dating techniques (if it is a dating technique at all). It may more likely be a cultural / industrial classification technique. E.G. cultivation of certain plants is a key characteristic of the transition from hunter/gatherer (nomadic) to agricultural, neolithic (more settled, at least seasonally) cultures.

There may be literature among the paleo-botanists as well.