Seasonal dynamics of ground cover in <i><scp>C</scp>irsium arvense</i> – a basis for estimating grazing losses and economic impacts

Bourdôt, G. W.; Hurrell, G. A.; Trolove, M.; Saville, David J.

doi:10.1111/wre.12195

Cited by 6 publications

(5 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The trajectory for aerial shoot density is similar in shape to that calculated for percentage ground cover in Bourdôt et al. (). Both the aerial shoot and creeping root trajectories are realistic, corresponding to values that have been observed on medium to highly infested sheep and beef farms (Cripps et al.…”

Section: Resultssupporting

confidence: 74%

Mowing strategies for controlling Cirsium arvense in a permanent pasture in New Zealand compared using a matrix model

Bourdôt

Basse

Cripps

2016

Ecology and Evolution

View full text Add to dashboard Cite

Defoliation has frequently been proposed as a means of controlling Cirsium arvense (L.) Scop. (Californian thistle, Canada thistle, creeping thistle, perennial thistle), an economically damaging pastoral weed in temperate regions of the world, but its optimization has remained obscure. We developed a matrix model for the population dynamics of C. arvense in sheep‐grazed pasture in New Zealand that accounts for the effects of aerial shoot defoliation on a population's photosynthetic opportunity and consequential overwintered root biomass, enabling mowing regimes varying in the seasonal timing and frequency of defoliation to be compared. The model showed that the long‐term population dynamics of the weed is influenced by both the timing and frequency of mowing; a single‐yearly mowing, regardless of time of year, resulted in stasis or population growth, while in contrast, 14 of 21 possible twice‐yearly monthly mowing regimes, mainly those with mowing in late spring, summer, and early autumn, resulted in population decline. Population decline was greatest (with population density halving each year) with twice‐yearly mowing either in late spring and late summer, early summer and late summer, or early summer and early autumn. Our results indicate that mowing can be effective in reducing populations of C. arvense in pasture in the long term if conducted twice each year when the initial mowing is conducted in mid spring followed by a subsequent mowing from mid summer to early autumn. These mowing regimes reduce the photosynthetic opportunity of the C. arvense population and hence its ability to form the overwintering creeping roots upon which population growth depends.

show abstract

Section: Resultssupporting

confidence: 74%

Mowing strategies for controlling Cirsium arvense in a permanent pasture in New Zealand compared using a matrix model

Bourdôt

Basse

Cripps

2016

Ecology and Evolution

View full text Add to dashboard Cite

show abstract

“…Variegated thistle caused a 5.3% decline in total pasture production but saw total income decline by 32%. Bourdôt et al (2016) used a national model to estimate potential loss of income 8 pasture production may be greater than those demonstrated here and may be the effect illustrated in Figure 1 when comparing the pasture growth profile from Farmax with the thistle impacted growth.…”

Section: Changes In Stock Policymentioning

confidence: 99%

“…The impacts of Californian thistle on ground cover and, therefore, potential pasture growth have been quantified from the model produced by Bourdôt et al (2016). The pattern of impact throughout the year is depicted in Figure 1.…”

Section: Predicting the Impact Of Thistle Controlmentioning

confidence: 99%

See 1 more Smart Citation

Farm systems analysis of two thistles of differing seasonal pasture growth impacts in North Island hill country

Stevens

Tozer

Rhodes³

et al. 2019

Journal of NZ Grasslands

View full text Add to dashboard Cite

Models for infestations of Californian thistle (Cirsium arvense) and variegated thistle (Silybum marianum) were used to modify fortnightly pasture growth forecasts using Agricultural Production Systems simulator software using climate and soil data from a single farm (Tangihanga Station) over four aspects and three slope classes. Modelling using Farmax software was used to estimate profitability using the current farm enterprises with or without either the Californian or variegated thistles. Modelled pasture production, based on field observations of thistle infestation, was similar to estimates using animal intake (from Farmax). Californian thistle reduced pasture production in summer and autumn, while variegated thistle reduced autumn, winter and spring pasture growth. Californian thistle had a much greater overall presence (20%) than variegated thistle (9%). Both types of thistle reduced the potential to finish lambs in summer and reduced ewe wintering numbers, while the presence of Californian thistles also reduced over-wintering cattle numbers, by reducing summer-autumn pasture accumulation. Cost of control for Californian thistle ($233/ha) over two years was higher than for variegated thistle ($184/ha) over four years. Net profitability was reduced by 24% ($87/ha) by the presence of Californian thistle, and by 37% ($135/ha) by the presence of variegated thistle.

show abstract

“…However, most populations of Cassida rubiginosa in New Zealand appear to persist at densities less than 10 larvae per shoot, with only occasional outbreak populations exceeding this density (M. Cripps, personal observation). Since Cirsium arvense remains one of the most economically damaging pasture weeds in New Zealand (Bourdôt et al 2016), there is high demand for this biocontrol agent, especially for hill-country pasture where spraying herbicide is not practical or economical.…”

Section: Introductionmentioning

confidence: 99%

Initial test of a semiartificial diet for the thistle biocontrol beetle, Cassida rubiginosa

Cripps¹,

Mills²,

Villamizar³

et al. 2022

NZPP

View full text Add to dashboard Cite

The thistle biocontrol beetle, Cassida rubiginosa is established in New Zealand, but often not sufficiently abundant to achieve control of the weed, Cirsium arvense (Californian thistle). Mass production of the beetle could enhance biocontrol efforts through supplemental and inundative releases. We carried out an initial test of a semiartificial diet (containing host plant material) designed for laboratory mass production of the beetle. Larval survival rates were tested on diets with three different concentrations of preservatives (full, half, and no preservative), and compared to a positive control (leaf disc of Cirsium arvense), and a negative control (water). Only larvae on the leaf disc developed to the adult stage. Of the diets, the longest survival time was on the full preservative diet, with a mean mortality time of 8.8 ± 0.6 days, and a maximum survival time of 21 days. Although no larvae completed development on the diets, some important progress was achieved: (1) Neonate larvae were mobile on the diet; (2) larvae fed on the diet; and (3) there was adequate control of microbial contamination without being acutely toxic to the larvae. Further development of a diet for Cassida rubiginosa should focus on nutritional components for larval development.

show abstract

Seasonal dynamics of ground cover in Cirsium arvense – a basis for estimating grazing losses and economic impacts

Cited by 6 publications

References 34 publications

Mowing strategies for controlling Cirsium arvense in a permanent pasture in New Zealand compared using a matrix model

Mowing strategies for controlling Cirsium arvense in a permanent pasture in New Zealand compared using a matrix model

Farm systems analysis of two thistles of differing seasonal pasture growth impacts in North Island hill country

Initial test of a semiartificial diet for the thistle biocontrol beetle, Cassida rubiginosa

Contact Info

Product

Resources

About