Planting breaths of fresh air

One of the latest projects in an ambitious tree-planting program will help future campers at Camp Couchiching breathe easier.

About 600 trees were planted in May at the Ramara Township camp as part of the province's 50 Million Tree program, which aims to have that many trees planted in southern Ontario by 2020.

The United Nations declared the planting to be the largest project of its kind in North America.

Campers celebrated that accomplishment Saturday with the "ceremonial mulching" of a tamarack tree.

Twenty years ago, between 20 million and 30 million trees were being planted in Ontario each year.

Funding cutbacks in the early 1990s caused that number to drop. By 2006, two million trees were being planted annually.

Trees Ontario and its partners planted a million more than that this past spring alone.

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Tree Leaves Control Their Own Temperature, Study Reveals

The temperature inside a healthy, photosynthesizing tree leaf is affected less by outside environmental temperature than originally believed, according to new research from biologists at the University of Pennsylvania.

Surveying 39 tree species ranging in location from subtropical to boreal climates, researchers found a nearly constant temperature in tree leaves. These findings provide new understanding of how tree branches and leaves maintain a homeostatic temperature considered ideal for photosynthesis and suggests that plant physiology and ecology are important factors to consider as biologists tap trees to investigate climate change.

Tree photosynthesis, according to the study, most likely occurs when leaf temperatures are about 21°C, with latitude or average growing-season temperature playing little, if any, role. This homeostasis of leaf temperature means that in colder climates leaf temperatures are elevated and in warmer climates tree leaves cool to reach optimal conditions for photosynthesis. Therefore, methods that assume leaf temperature is fixed to ambient air require new consideration.

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