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Red Pine

Pinus resinosa

There is one red pine in the Park, in the southeast triangle. See Wikipedia entry here.
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Red pine against a beautiful backdrop in July
Red pine factoids:
  • although a native species, it is sometimes called the Norway pine
  • Intolerant of shade, which may explain the stunting of the tree in our Park
  • the leaves, or needles, come in twos on the fascicles, and usually break when bent
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Four different pines in the Park
Far left is a fascicle with three needles from a pitch pine, along with its spiky cone.
Going right, next is a black pine fascicle with two long stiff pointy needles, along with its cone.
Next is a white pine fascicle with five needles. There were no female cones on the white pine this July.
At far right is a red pine fascicle with two short, brittle needles, Again no female cones in July.
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Red male cones in clusters on the left and a larger old female cone on the right in mid-April
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Red male cones in mid-April, most having fallen off leaving a corn-cob like base
Botany 101 Bonus
 
Our red pine is a fairly short tree, especially compared to the nearby white pine. Trees make wood, i.e. more tree, by converting carbon dioxide and water into sugar and wood using the energy of the sun. The carbon dioxide enters the tree via tiny openings in the needles. But how does the water get into the needles, where photosynthesis occurs?

The wood of the trunk of the tree is made up of tiny continuous tubes that conduct the water from the soil to the utmost heights of the tree. For the red pine, that trip is only 15 feet, but for the white pine it will eventually be up to 150 feet. Water in the needles evaporates from those tiny holes in the needles or leaves. Water molecules are attracted to other water molecules (called cohesion). This is why water "beads up" on a waxed surface. The water molecules are also attracted to the material making up those tiny tubes (called adhesion). As the water evaporates from the needles, more water replaces it by "pulling" the water up from the water in the ground by these properties of cohesion and adhesion. This evaporation of the water from the underside of needles and leaves acts for the whole forest like our sweating does for our bodies: a cooling effect. Combine this with the shade from the trees and it is no wonder our Park is a "cool" place to hang out in the summer.

The sugar maples in the park pull water up by the process of evapotranspiration described above, but in the spring also "push" the water up from the roots. Maples can concentrate sugar into their roots and thereby draw water into the roots by osmosis. This "root pressure" is responsible for the free flow of sap when you tap a maple tree in late February, even before there are any leaves to evaporate water from.

 
You can see this same process occur when you dangle the corner of a paper towel in a glass of water (add some food coloring for more drama). The water will gradually work its way up against gravity. After all, a paper towel is just wood!
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