Porina Control Research Articles

How to optimise pasture production off uncultivatable hill country

Around 70 percent (guesstimate) of New Zealand's sheep and beef population is farmed on uncultivatable hill country. There are large areas where individual farms have less than ten percent available for cultivation. Wairere is such a property. Originally the southern end of the "seventy mile bush", the soils are poor, derived from sandstone and clay, with pHs of 4.9-5.2 and phosphorus (P) levels of 1-2. Following initial land clearing there were several rounds of reversion to Manuka until the mid 1960s when my father John embarked on a programme which included large inputs of lime, at 5 t/hectare, super at 1 t/hectare, and DAP at 100 kg/hectare, all flown on in the first 28 months. This programme took from 1965 to 1982. I personally spent nine months cutting scrub—more recently I have been a shareholder in a manuka honey company planting scrub, how things go round! This programme was accompanied by subdivision and provision of stock water by the construction of dams. There were invasions of porina and manuka beetle following development, and porina control is still required on a regular basis. Wairere has run performance recorded sheep since 1967, based on a registered Romney stud started by my grandfather in 1929. We winter around 9500 sheep and 340 cattle on 1070 effective hectares. The 5300 ewes wean 145 percent average; the 2000 ewe hoggets (all in lamb) wean around 1700 lambs. All hoggets have been mated for the past 50 years; the 1800-2000 ram hoggets are culled lightly in late winter, and taken through to private sale in November; the 300 cows (replacements bought in) calve from mid October, with most wearers sold in April.

Evaluation of diflubenzuron for porina control in South Otago

Previous work assessing the suitability of using diflubenzuron for porina control in New Zealand has shown it to be effective in most areas of New Zealand, but results from the southern South Island have been inconsistent. Trials were conducted in South Otago in 1994, comparing two rates of diflubenzuron, and 1995, comparing diflubenzuron with chlorpyrifos. Diflubenzuron, applied at the manufacturers recommended rate, gave 78% and 80% control of porina in 1994 and 73% control in 1995. This compares with an average of 95% control achieved using chlorpyrifos in 1995. The results show that diflubenzuron can give significant levels of control of porina in South Otago and is a viable option for farmers.

Efficacy of entomogenous nematodes for control of porina (Wiseana cervinata) in Canterbury pastures during winter

Abstract Entomopathogenic nematodes were tested for their efficacy against porina larvae (Wiseana cervinata) in pot and field trials in Canterbury , New Zealand during winter. Four nematode strains, Steinernema feltiae (= bibionis) CA, S. glaseri, Heterorhabditis sp. HL81, and H. bacteriophora V16 were used in a pot trial at temperatures between 3 and 12°C. S. feltiae CA was the most pathogenic strain causing 100% mortality at the highest rate of application. S. feltiae CA and H. bacteriophora V16 were tested further in the field. Applied in June at a rate of 4 × 105 infectivesl m2, S. feltiae CA provided a 60% reduction in porina numbers during the winter months, whereas H. bacteriophora V16 provided a 25% reduction in spring.

Control ofWiseanaspp. (Lepidoptera: Hepialidae) by sheep grazing in South Otago

Abstract Porina damage to pasture is a serious problem in Otago and Southland and low-cost control methods such as heavy stocking are attractive alternatives to the use of insecticides. In South Otago, density of larvae ofporina (Wiseana spp.) in pasture was reduced on average by 69% by grazing with 1000 ewes/ha for three periods of 3–5 days in January, February, and March, and by 32% by one period of 3–5 days in February. Similarly, four, 3day periods of grazing at 500 eweslha caused a 47% average reduction, and corresponding mowing of the pasture to 1 em in height with a rotary mower caused a 32–42% reduction. Three periods of grazing with 1000 ewes/ha increased pasture production by 34% in the following spring and early summer. Four periods of grazing at 500 ewes/ha increased production by 35% at one site. Single periods of grazing and mowing had no effect on pasture yield. Multiple grazings of 3–5 days with 500–1000 ewes/ha is a viable option for porina control.

Chemical control of porina in South Otago sheep pastures

Abstract Granular, emulsifiable concentrate and micro-encapsulated EC formulations of diazinon, fenitrothion, and chlorpyrifos, micro-encapsulated methyl parathion EC. and the growth regulator diflubenzuron were compared for control of porina (Wiseana spp.) in three trials in Otago. Porina mortality from fenitrothion EC applied at different times between February and June was compared to that obtained with diflubenzuron applied to pasture at different times between March and June and at a range of application rates. Fenitrothion EC. chlorpyrifos EC. and methyl parathion MEC caused the highest mortality of porina with fenitrothion EC applied in late May at a rate of 1.1 kg a.i./ha being the most cost-effective. However, chemical control of porina may not be economic at current prices for chemicals and pastoral products. Diflubenzuron did not appear to control porina effectively in these South Otago trials regardless of rate or time of application.

Diflubenzuron for porina control in otago

Diflubenzuron for porina control in otago

Porina control in Waikato dairy pasture

Porina control in Waikato dairy pasture

Conventional and microencapsulated spray and bait formulations for porina control

Conventional and microencapsulated spray and bait formulations for porina control

Field evaluation of baits for porina control

Field evaluation of baits for porina control

Preliminary field studies on the use of an indigenous parasitic nematode for control of porina

Preliminary field studies on the use of an indigenous parasitic nematode for control of porina

Possible new insecticides for porina control

Possible new insecticides for porina control

Porina control: spring pasture damage

Porina control: spring pasture damage

Porina control in Canterbury, 1967

Porina control in Canterbury, 1967

Pasture response following insecticide treatment for the control of porina

Pasture response following insecticide treatment for the control of porina

Control of porina with fenitrothion

Control of porina with fenitrothion

Porina control in Canterbury, 1965

Porina control in Canterbury, 1965

Results of trials for the control of porina in the Nelson district

Results of trials for the control of porina in the Nelson district