Hello Lorraine,

I am not an expert on identifying mushrooms by photo however good it is. There are a lot of things to take into account and I think you should try and get in contact with somebody local and knowledgeable to go for a mushroom hunt. In addition to that France got their own laws about picking mushrooms:
http://paris.angloinfo.com/countries/fr … hrooms.asp
A guide to French mushrooms can be found here:
http://www.mycofrance.com/
and they give advice, too.

Hope that helps for an edible meal
Tanja

Hello,
A very interesting question and not that simple to answer. There are several possible explanations.
1) Within a species, individual trees develop leaves consistently early or late; despite strong environmental variation. It therefore is likely due to genetic differences.
2) There is a variation between different species. It is therefore possible that the free-standing tree leaves out earlier because of its species. Species which leave out earlier are normally less affected by cold temperatures in spring or frost.
3) The difference in the understory growth is likely to cause a variation in soil temperature which could cause the difference.
However, I am afraid I am not familiar with the specific vegetation in Ohio and without knowing the species I can not tell you the specific reason for the phenomenon.

Hello Kelly,

In your title you were specifically refering to bryophytes but in your question you just spoke about plants. Therefore I refer to plants as well.

The uptake of minerals by the plants is depending on different factors:

•    Accessibility of the mineral, which means the mineral, must be in a form which can be taken
                up by the plant.
•    Availability or concentration of the mineral.
•    The movement of the mineral in the soil.
•    Whether the roots reach an area in the soil with fresh mineral supplies.
•    Surface area of the root – the larger the area the more uptake is possible.

The minerals follow the same pathways as water. However, some mineral ions e.g. NO3- distribute in-between the cells.
The big contrast between the uptake of water and the uptake of minerals is that some minerals are taken up actively (the active uptake is due to a proton pump). Therefore the concentrations within the plant can be much higher than in the soil.

Hello Feiv,

As far as I am aware it is not an advantage for the tree to have red leaves. The reason for it is a mutation resulting in a missing enzyme. An example for a tree with red leaves is copper beech. The enzyme normally removes the plant pigments which can be found in the epidermis of young leaves. The one which is not removed in the red leaves is called Anthocyane is used to absorb UV-radiation. As the Anthocyane is not decomposed the epidermis of the leave is not see-through but red or reddish. Therefore the green of the leaf inside does not shine through. Throughout the growing period the red coloring is lost and the leaves appear green.

Bye
Tanja

Joakim

A very interesting question indeed.
The processes in the leaves in autumn can be separated in two parts: the reversible, called "senescence" and the irreversible, the "programmed cell death". However, the use of both terms can be overlapping. A "re-greening" of a leaf can only happen in the very early stages of yellowing. Only few cases are reported. In 1974 WR Krul noted that removal of the epicotyl of soybean can reverse visible senescence. There is a detailed discussion about it by Wouter G. van Doorn and Ernst J. Woltering in the Journal of Experimental Botany, Vol. 55, No. 406, pp. 2147–2153, October 2004, called "Senescence and programmed cell death: substance or semantics?"

Tanja

(posted in Plants & Fungi)

What you could use is "agar". It is a nutrient solution and functions as media for fungi and bacteria; I grow my (tree) seeds on it and they are doing fine and germinate quickly.

You can find some general information on: http://en.wikipedia.org/wiki/Agar

A recipe is given on this page: http://www.sciencestuff.com/playground/ … wder.shtml

Good luck and great idea!

Dear Laurie,

I am afraid there is no easy answer to your question. Recycling saves mainly commodities or raw materials. Taking the example of paper you need to harvest less trees if you re-use old paper. The efficiency nowadays is nearly 100%. Similar methods are used for glass and plastic bottles; cleaning and re-using them saves the energy and commodities to produce new bottles AND you reduce wast! Nearly everything can be recycled: plastic, glass, paper, cloths, metal, rubber... sometimes a completly new product  appears, for e.g. furniture out of an old car tyre.
Therefore it is really hard to give an overall figure as you have to think about who is recycling what, how much energy is needed to recycle, how much energy is saved not having to take of the waste etc. To get an idea have a look on these webpages:
http://www.earth911.org/master.asp?s=li … Facts.html
http://www.eia.doe.gov/kids/energyfacts … glass.html

And the most important part is: it does help the environment if you do recycle!

Hi Stuart,
You are right, an upward trend is due to a milder climate; however, the question what to understand under global warming is more difficult to answer. If we look at the big picture the climate on earth has changed quite drastically - just think of Hannibal crossing the alps with elephants in Roman times. We have evidence that it was warmer then, than it is today. Going along with higher reaching forests. About 150 years ago it was very cold - a little ice-age. Climate is therefore changing in intervals and whether we are still on an upward trend after the little ice-age or we have global warming (this expression nowadays indicates the human influence)is difficult to say. We are working hard to seperate the signals we get from the trees to be able to quantify the human and the natural warming.

There were several periods of warmer climate, the last one is about 1000 yrs ago and called the 'medieval warm period'.

Another period is in the middle Pliocene (ca. 3 Million Years Ago) when it was generally warmer than present, particularly at middle to high latitudes. It has been suggested that this period may represent an analogue for future climate change. Mechanisms that have been proposed to account for this warming are enhanced thermohaline circulation and/or greater concentrations of CO2 in the atmosphere. In the European and Mediterranean region the climate might have been warmer by 5 °C, wetter (by 400-1000 mm/yr), and less seasonal than present.

Some remarlable plant fossils were found along the British cliffs e.g. in the Bournemouth cliffs (which are notable for sands and clays of Eocene age). The fossil leaves seem to indicate that in Eocene times there was here an unusually warm environment even thought the palaeolatitude would normally suggest temperate rather tropical conditions .

Probably the best link about the different periods is this one here: http://www.awi-bremerhaven.de/Modelling … riods.html

The question concerning the latitude is a quite different. What is now the British Isles moved due to plate tectonics over the globe. Therefore it was once closer to the equator and the climate was therefore comparable to the tropics today.

For the determing factors of tropical climate this site here gives some good background: http://www.ace.mmu.ac.uk/eae/Climate/Ol … imate.html