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Northern Red Oak

Quercus rubra

There is only one red oak in the Park, in the southeast triangle, easily identified by its leaves and acorns. See Wikipedia entry here. 
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The northern red oak, or champion oak, is a native of North America, in the northeastern United States and southeast Canada. It grows best in good, slightly acidic soil.
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Slender red oak in southeast triangle
Red oak factoids:
  • Sometimes called the "northern" red oak to distinguish it from the southern red oak, also known as the Spanish oak (Quercus falcata)
  • Called the "red" oak because of the fall color and also due to the hint of red in the leaf veins on the underside of the leaves.
  • Its acorns are a food for squirrels, and if the acorns are chopped up and leached in water to remove the bitter tannins, can be consumed by humans.
  • Red oak acorns have tiny hairs on the inner surface of their acorn caps, whereas white oak acorns are hairless.
  • Trees that shed their leaves in the fall are called deciduous trees. Oaks are deciduous,  but the dead oak leaves often stay on the tree through the winter until new leaf buds form in the spring (a trait called marcescence). Beeches similarly hold on to dead leaves.
  • Some oaks, like the white oak, make acorns every season. The red oak makes a crop of acorns every other season. The tree flowers every year, but in the first year of the cycle the acorns are tiny stubs by fall, and only fully mature the following autumn. The red oak and other two-year oaks like the black oak, pin oak, and scarlet oak tend to have pointy leaves, while the one-year oak leaves have more rounded tips. Our tree produces in odd-numbered years.
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Red oak leaves are more pointed at the tips than other oaks
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Male flowers on catkins on April 16.
Free-standing red oaks attain reproductive age at about 25-30 years.
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Red oaks have separate male and female flowers on the same branch. The male flowers are quite conspicuous on their dangling catkins. The tiny red female flowers will generate an acorn if fertilized.
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Oak fruit, also called an acorn, in August.
Botany 101 Bonus
 
Trees are not mobile. They cannot walk away from insect pests or competing plants. For this reason they often contain within their roots, stems, and leaves chemicals that are distasteful or toxic to insects. Some trees also contain chemicals that inhibit the growth of surrounding plants. These plants that inhibit the growth of other plants via chemicals are termed allelopathic. 
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The exemplar of a strongly allelopathic plant is the black walnut tree, under which almost nothing will grow. You wouldn't want to plant shade-loving plants or even grass under a black walnut. There are many exceptions in biology, and even near the strongly allelopathic black walnut, some species, like our Park's honey locusts, can grow. There is a constant arms race over evolutionary time between plant defenses and other plants' counter-strategies.
 
The red oak is moderately allelopathic, with the allelopathic chemicals contained in roots, stems, and leaves. 
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