Eat forage.

There are usually two flights per year with the first occurring from late spring/early summer and the second from late summer/early autumn. It is during the nymph stage that feeding damage occurs to plants.
 
Brassica crop plantings from November to March are usually the most vulnerable to Aphid attack.

• Ultrastrike seed treatment
• Aphid-tolerant varieties
• Application of insecticide
• Recognise flight periods and control infestations early

Larvae appear from October onwards and feed on tillers causing them to yellow and then brown and ultimately die. Poor resulting of pasture is often mistakenly attributed to other factors such as drought. Adult weevils feed all year round on leaves leaving narrow rectangular holes in the leaves usually near the tips. 

• Use of Ultrastrike brassica or Superstrike Grass seed treatment to protect seedlings
• Removal of host ryegrass plants
• Recognise flight periods and control infestations early
• Application of insecticide
• Use tolerant species (cocksfoot, tall fescue)
• Use of grasses with standard, AR1, Endo5, AR37 or MaxP endophytes

A fungal disease that rots brassica leaves

• Bury previous crop debris
• Crop rotation

An infection that can occur in all brassica species and is a soil borne fungus that can remain dormant in the soil for many years and can re-emerge only when a brassica crop is planted. This makes it extremely difficult to eradicate or prevent. 

• Crop rotation
• Use kale

Symptoms characterized by either the failure of seedlings to emerge or the toppling over and subsequent death of newly emerged seedlings. Plants that are affected post-emergence usually appear shriveled and discoloured at the shoot base. Damping off pathogens cause infection over a wide soil moisture and temperature range. 

• Use of Superstrike grass or brassica seed treatment to protect seedlings
• Chemical control

Lay eggs in brassica plants and can cause damage to leaf and seeds.

• Removal of old brassica plants which may act as carry-over hosts
• Application of insecticide

Dry rot appears in a crop as a leaf spotting, small green-grey lesions about 3-5 mm in diameter appear on young leaves from around the 3-4 leaf stage onwards (in a swede crop this is often
between Christmas and New Year). 

• Use kale
• Crop rotation and minimise crop residual in second year crops

Plants wilt and may eventually die due to the roots being eaten away. Yellow patches of stunted growth appear in the pasture and plants may be readily pulled from the ground due to loss of roots. Period of maximum feeding by grubs is in autumn and early winter.

• Heavy grazing (March-June) to reduce Grass Grubs' feed supply
• Through cultivation in spring
• Granular intesicide sown in the root zone
• Heavy stocking or rolling to squash larvae
• Use of Superstrike Grass seed treatment to protect seedlings

Eat forage leaves

• Good seed bed cultivation and compaction
• Application of insecticide

Eat forage causing damage to leaves

• Removal of alternative hosts (e.g. fathen, sowthistle etc.) to prevent build-up of numbers

Discoloured spots on brassica leaves

• Insecticide 

Circular lesions on brassica leaves

• Crop rotation

Feeding takes place mainly at night, and will be shown as holes in the leaves, stems or roots. Slime is a good indication of slugs or snails.

• Monitor slug numbers
• Slug Bait application

Damage to brassicas may occur as soon as the seed shell is shed and the cotyledons emerge, and as a result the stems supporting the cotyledons are often damaged or destroyed before they emerge above the soil. With mouthparts adapted for chewing, Springtail chew small holes or pits in leaf surfaces.

• Ultrastrike Brassica or Superstrike Brassica seed treatments
• Contact insecticide
• Both seed treatment and a contact insecticide is recommended in no-tillage situations

When feeding on brassica seedlings the developing plants become weak at ground level and often fall over. Nysius damage is often identified by a “ringbarking” effect at the base of the plant. Nysius are most active in dryland regions with increased plant damage occurring under hot, dry conditions over the summer months. Nysius prefer an open ground cover.

• Ultrastrike Brassica seed treatment to protect seedlings
• Control of weeds around crop borders will help reduce localised numbers
• Application of insecticide

Eat forage leaves

• Natural predators (e.g. hoverfly, harvestman and parasitic wasps)
• Removal of old brassica crop, debris and weeds to prevent overwintering and localised build-up

Eat forage leaves

• Thorough cultivation should be carried out through late spring and summer prior to sowing in infested areas; clean fallow reduces numbers
• Apply insecticide sown with seed