Too Much Sugar!
In the fall, the hills adjacent to the Missouri and Mississippi rivers seem ablaze with brilliant orange sugar maples. Few trees are as attractive as a sugar maple in autumn, but there is something haunting in all that orange.
Not long ago, these same hills contained a lot more of the reds, purples and yellows of oak and hickory. Slowly but surely, the oranges are taking over, indicating that the river hill forests are changing, and not for the better.
We have long had some sugar maple in our woods. In the last 50 years, however, the amount of sugar maple has increased dramatically. This is especially true in counties adjacent to the Missouri and Mississippi rivers, where land is especially productive because of loess, or wind blown silt. Loess is blown from the river bottoms and deposited on nearby slopes. In some areas, loess is more than 100 feet deep. In areas like these, sugar maples are overtaking most other forest vegetation.
The primary reason for the maple takeover is that over the last 50 or so years, we have stopped fires from burning our woods. Native Americans commonly used fire as a tool in Missouri. They burned the landscape to aid in hunting and fighting wars. They also used fire to improve wildlife habitat, which helped ensure an abundance of game. The first European settlers also used fire, primarily to create and improve pasture lands.
Fire played a huge role in shaping the composition of our woods. Oaks and hickories are relatively tolerant of fire. Their thick bark helps protect them from intense heat. Smaller seedlings and trees may be "top-killed," but their deep root crown allows them to resprout quickly and vigorously.
Maples have thinner bark at all ages and are much more vulnerable to fire. Until the widescale suppression of wildfire, maple growth was limited to protected sites that did not burn often. Now, maples grow uncontrolled in many places.
Where there is no fire, maples have an advantage over many oaks and hickories. Maples thrive in shaded conditions. They grow quite well in the understory of an oakhickory forest. They'll persist for decades, and have a good, growing head start when a large oak or hickory tree dies or falls. Generally, the competition in a forest is for sunlight, and maples usually shade out young oaks or hickories.
Although maple trees are beautiful, allowing them to