CROP TREES
Sometimes forest landowners will favor certain trees
over others within their forestland because of their
management goals, such as timber quality, wildlife
habitat, esthetics, or nut production.
Those favored trees, called "Crop Trees", are given more
room to grow. Neighboring trees, that are crowding the
Crop Trees, are killed (but left standing). This is
termed "releasing the Crop Tree from competition"; each
Crop Tree will receive more sunlight, more water, and
more soil nutrients; it will respond by growing faster
and producing more seeds. In managing a stand for
Crop Trees, each small group of trees was judged
according to the management goals:
- Which tree has more valuable wood?
- Which tree is
growing straighter with fewer side branches?
- Which tree produces more nuts and seeds?
- Which tree produces seeds that are enjoyed by
wildlife?
- Which tree has already reached the canopy for
sunlight?
- Which tree produces seed that store well over winter?
- Which tree is growing more vigorously than others?
These decisions are not easy; but they are made knowing
that the Crop Trees will be healthier, grow more wood,
produce more food for wildlife, etc. The
killed trees are left to decompose and contribute to the
forest nutrients. In some cases, these trees are used by
wildlife for shelter, as a Snag Tree.
In most cases, the released Crop Trees will respond
dramatically. In one 54-year old forest stand, released
trees grew 4 inches in diameter over ten years while
those that were crowded grew only 1.8 inches. It has
also been shown in many studies that released trees
generate more seed because the food, water, and sunlight
is available to produce them. |