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hedging and ornamental value, and even distributed through the garden and nursery
<br />industry, buckthorn is now considered a "restricted noxious weed" by the state
<br />Department of Natural Resources. Since 1999, it has been illegal to import, sell, or
<br />transport buckthorn in Minnesota.
<br />2. A Little History...and Why Does This Matter?
<br />Common, or European, buckthorn (Rhamnus cathartica) is a woody understory shrub or
<br />tree that was imported to North America from Europe as popular hedging plants in the
<br />19th Century, but escaped from the confines of America's yards and gardens long ago.
<br />Buckthorn has encroached upon Minnesota's natural areas, establishing itself in our
<br />forests and oak savannahs. As happens with many introduced species, buckthorn found
<br />no natural controls in its new environment, such as insects and disease, or even native
<br />browsing. It quickly became an aggressive, invasive, nuisance plant, taking over the mid -
<br />layer of our Minnesota Big Woods Big Rivers areas and habitats. As a thriving flora, why
<br />is Buckthorn such a big deal? Common buckthorn has many competitive advantages
<br />over our native vegetation. It is extremely hardy, grows vigorously in almost any soil,
<br />and tolerates a variety of light conditions. Buckthorn leafs early in the spring, and
<br />doesn't drop its leaves until very late in the season, allowing it to photosynthesize well
<br />before and well after much of the native understory vegetation, outcompeting other
<br />native plants for resources. Despite looking like a lush, green, thriving layer of
<br />understory to human eyes, buckthorn offers little to the natural environment. Insects
<br />don't eat the leaves, and the deer do not browse on buckthorn either, which puts
<br />additional pressure on the already straining native vegetation. Birds will eat the berries,
<br />but usually only when desperate for forage, as they offer little in nutrition, however, do
<br />act as a powerful laxative, allowing the plant to effectively disperse seeds to new areas.
<br />3. Proper Identification
<br />One of the first, and most important, steps in buckthorn
<br />removal is proper identification. Buckthorn bark can look
<br />very similar to native plums, juneberry, or cherry, so care
<br />must be taken to only remove the invasive, but leave
<br />behind the beneficial. Autumn is a great time for
<br />buckthorn removal processes. Because it holds its leaves
<br />much longer than other woody vegetation, it is often
<br />easier to identify in the late fall. Buckthorn bark is
<br />smooth and gray with small white bumps on young plants, changing to a
<br />bark as the plant gets older with occasional sharp protrusions. A cut in the
<br />reveal yellow/orange sapwood underneath. Branches often end in a sharp
<br />are a broad elliptic, growing slightly alternate from the
<br />stem, almost opposite, with a deeply veined, dark, glossy
<br />green color, very small edge serrations. Small nodules,
<br />where the leaf stem meets the branch, that some say
<br />look like a deer's hoof print, and may be a part of how
<br />the plant got its name, are also an identifier.
<br />ragged, flaky
<br />bark will
<br />thorn. Leaves
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