Agriculture Reference
In-Depth Information
Many readers already have located their sites and established their orch-
ards. In these cases, adjustments to the site can help reduce disease prob-
lems. Practices such as installing drain tiles or otherwise improving water
drainage in an orchard help reduce root problems. Eliminating plants that
serve as alternate hosts for fruit tree diseases in and around an orchard
helps reduce the amount of inoculum your trees are exposed to, thereby re-
ducing infections. Proper orchard layout, pruning, and training create open
canopies with good light exposure and air movement. Opening the canopy
lowers the humidity around the fruit and facilitates rapid drying of the
leaves and fruit after rain. Effective orchard floor management creates a bio-
logically diverse and active soil that promotes healthy, vigorous root systems
and tree canopies. Proper nutrition and crop load management help maintain
the moderate vegetative growth and sustainable yields necessary for long-
term tree health.
Disease Management Strategies
Even if you use every cultural practice and pesticide available, if you plant
a highly disease-susceptible fruit variety in an area where that disease is
severe you can expect serious problems. The most important disease man-
agement practice is to select crops and varieties that are resistant to the dis-
eases in your area. In the southeastern United States, for example, plum leaf
scald is a very serious disease for which European plums have no resistance.
Several North American plum species and hybrid varieties, however, are res-
istant to leaf scald and other diseases prevalent in that warm, humid climate.
and recommended growing regions. By following these guidelines, you can
usually reduce disease problems to the point that they can be managed with
cultural practices and organic pesticides. It is especially critical that growers
in eastern North America, who typically deal with humid climates and high
disease pressures, select the right crops and varieties. Organic fruit growers
in more arid regions with low disease pressures have greater flexibility in
what crops and varieties they grow.
