Insects

There are two species of insects that are found around our greens, insects harmful to plant life and beneficial insects which help to control some of the harmful insects.

Effective control
To effectively control insects it is important to understand them better. Because insects are cold-blooded, the outside temperature regulates everything they do. Their hard external skeleton (exo-skeleton) also becomes resistant to chemicals.

Their development or metamorphosis takes place in the following sequence:

• Egg
• Nymph
• Adult

For an insect to grow, it has to shed skin (moult). Some pesticides disrupt this moulting process.

It is important to note that if you use and insect growth regulating (IGR) pesticide when the insect is in the mature state, you are wasting time and money.

In order to cope with insects it is important to try and create the necessary environment to do so.

One such area is Thatch management, as the more thatch you have the more insects there will are likely to be.

Three of the most important factors in insect control are:

• Timing (most important)
• Selection of product
• Technique

There are essentially two distinct groups of insects that are commonly found:

• Above ground, e.g. caterpillars
• Subterranean insects, e.g. mole crickets

Subterranean insects are protected by the soil around them, and it is difficult to get the insecticide to them. When the soil is dry, subterranean insects move down into the ground because they need a reasonable measure of soil moisture. If there is dry organic matter, the insecticide tends to stick to it and is unlikely to work effectively.

There are two options that can be used to create the environment most conducive to treatment:

• Heavily irrigate the area so that the grubs move up and then apply the insecticide and irrigate afterwards
• Wait until you get good rain, because though the grubs are larger, they are then closer to the surface

Pesticides

The challenge for greenkeepers is to move to the newer pest control systems as they must realize that they are in control of a living eco–system, and consequently pesticides should only be used when and where they are needed.

Insecticides penetrate insects in three different ways:

• through the outer covering (skin) – contact poisons
• through the mouth – stomach poisons
• through the breathing holes (spiracles) – fumigants

Common Insects

Nematodes

Symptoms
Damage to roots is the most important effect of nematodes on turf grasses. Roots may be killed or stunted, resulting in poorly developed, shallow root systems. The above ground symptoms are slow growth, thinning of the turf, poor response to adequate fertilization and irrigation, rapid wilting during dry weather and weed invasion. A Nematode assay of soil samples is the only sure way of determining if nematodes are a problem since other diseases or nutritional problems may produce similar symptoms.

Controlling Nematodes
Good management practices will help overcome the effect of many nematodes and are the only practical means of control on low maintenance areas. When the sting nematodes are present, nematicides are usually needed on highly maintained areas.

The following can be used to help control Nematodes:

• Crop Guard – Use per instruction
• Dark Brown sugar or Molasses added to fertiliser drum in the following quantities 10 kg Dark Brown sugar and 5 litres of Molasses

Black Maize Beetle

Cut Worm

Army Worm

Sod Webworm

Sod Webworm