Groundcover management and beneficials
Groundcovers not only help with erosion control, organic matter and water penetration but are also a potential source of beneficial insects.
GVB and BFC do have some plant hosts that can occasionally grow in the interrow (silverleaf nightshade, amaranthus, ink weed) but generally pest of macadamias do not breed in the interrow.
This provides opportunities to build up natural enemies.
Good ground cover growth and diversity including flowering and high pollen grasses provide a home for a myriad of insects that are not pests of macadamias.
These insects are food for various predatory insects which will also have some impact on our in-tree pests and can help the farm be more resistant to pest incursions.
They also provide a buffer in the system and give you more time to make spray decisions.
At this stage, our suggestions are:
Reduce mowing when you can. Try and allow grasses and weeds to get to pollen and flowering stage before mowing.
Alternate row mowing or even better just mow half the row at a time - This gives insects a chance to move into the next row (or uncut area) and means food sources, pollen and nectar are more evenly available to insects. If you mow everthing at the same time, there is likely to be a crash in beneficial insect poplulations.
Leave a "Mohawk" strip down the centre of interrow during harvest if rows are wide enough. This will keep some plants and pollen available - its better than none.
Consider planting flowering plants down every third or fourth row. The more nectar available to parasitoids, lacewings, adult beetles and hoverflies, the longer they will live and the more offspring they will produce.
Lots more at: Inter Row Project and Ground Covers Web Pages
Nectar producing plants support parasitoids, lacewings, adult beetles and hoverflies. The will live longer and produce more offspring.
If you can, allow grasses to grow until they produce pollen.