Northern pin oak ( Quercus ellipsoidalis) has leaves that are 3-6 inches long, shiny green and widest in the middle, with deeply cut rounded sinuses and a flattish base (Photo 5). The bark is gray and smooth when young, becoming very dark with deep ridges that have horizontal breaks when older. The caps have rounded interiors, unlike the acorns of the northern red oak, which are flattened. The acorn nuts are half-covered by caps with loose scales. Leaves have hairs on the underside that are shed later in the season. They are shinier than the northern red oak and dark green above with a lighter underside. Leaves are 4-10 inches long with mostly five, sometimes seven bristle-tipped lobes. The bark is smooth, dark gray when young, becoming furrowed with flat-topped ridges forming stripes when older.īlack oak ( Quercus velutina) is the second most prevalent red oak in Michigan. The acorn is nearly round with a flat, thick cap reminiscent of a beret that covers one-fourth of the nut.
The sinuses reach less than half-way to the midrib. The leaf is typically dull green above and lighter green below with a smooth, reddish petiole measuring about 1-2 inches long.
It can be identified by the 5- to 8-inch-long leaf with seven to 11 bristle-tipped lobes. Northern red oak ( Quercus rubra) is the most prevalent oak species in Michigan. Bruce Kirchoff, Greensboro, NC, CC BY 2.0. Familiarize yourself with the terms used to describe leaves with the diagram below. While this can make identification more complicated, the following guide will help distinguish between the 10 most common species of oaks in Michigan. Oaks readily hybridize with other oaks in their groups, producing oaks with characteristics from both species. White oak, bur oak, swamp white oak, chinkapin oak and chestnut oak all belong to the white oak group. White oaks have rounded lobes or large regular teeth and acorns that mature in one year. Northern red oak, black oak, northern pin oak, pin oak and scarlet oak all belong to the red oak group. Red oaks have leaves with bristle-tipped lobes and acorns that take two years to mature.
All oaks belong to the genus Quercus, produce acorns and fall into two groups: red oaks and white oaks. The opposite is a simple leaf.There are 600 species of oaks worldwide, 10 of which are native to Michigan. Alternate leaves are located singly on the stem.Īxil – the upper angle between two structures (the leaf axil is between the leaf and the stem)Ĭompound leaf – a leaf in which the blade is subdivided into two or more leaflets. The black oak’s acorns mature the second year following their formation and tend to be much more bitter than the white’s.Īlternate – an unpaired arrangement – as opposed to opposite. The white oak’s acorns mature in the fall of the year that they are formed and are preferred by wildlife because they are sweeter than the black acorn. Oaks are divided into two groups: the white and the black (or sometimes called the red). Pistillate (female) flowers are inconspicuous, and staminate (male) flowers in some species appear as hanging catkins at the base of emerging growth of the season. Oaks are monoecious, having male and female flowers on the same plant. Identification is most reliable when using leaves from the crown branches. These factors make identification to the novice challenging. To add to the confusion, oaks hybridize between different species growing in close proximity to one another, in turn, producing leaf shapes having characteristics of both parents. Some species of oaks have a broad range of mature leaf shape and, in many, the leaves of new shoots are entirely different from the mature leaves.
0 kommentar(er)
