Orchard Floor Management
Chapter authors - Teryl Roper, Marc Rowley, Brent Black, Marion Murray
Orchardists often think of orchard pests as comprising only insects and diseases. Weeds are also orchard pests and are equally capable of reducing yield and fruit quality as insects and diseases. Weeds are pests by competing with trees for water, nutrients, and in extreme cases, light. On the other hand, orchard floor vegetation prevents erosion on slopes, improves trafficability especially during wet weather, may provide habitat for beneficial insects, and reduces mud.
The ability of weeds to compete with fruit trees is well documented. One experiment showed that grass growing near the trunk of apple trees delayed the onset of fruiting, reduced trunk circumference, and reduced shoot growth when compared to trees grown with bare ground surrounding them. Grasses were more competitive than broadleaf weeds. In another experiment, adding more nitrogen did not overcome the competition imposed by grasses.
Just as orchardists develop management plans to deal with insect and disease pests, an orchard floor management plan will help keep weeds in check. The orchard floor management plan is best determined before the orchard is planted. Management practices for orchard floor management should be executed in a timely manner during the lifetime of the orchard. This chapter describes some factors to consider while making decisions about how the orchard floor will be managed.