WINETECH Technical Yearbook 2021

dense stand and effectively suppress the narrow-

leaved ribwort (smal weëblaar/ tongblaar).

THE TERRACLIM PROJECT IS ONE of Winetech’s flagship projects that aims to improve the understanding of cli- mate change in the Western Cape and how the grapevine/plant responds to these changes. Specific objectives include building a comprehensive climate and terrain database, using new research and technologies to spatialise climate, terrain and vine- yard information. TerraClim uses automated functionality to collate, improve, spatialise and disseminate climate data, empowering the farmer and researcher to better analyse and mitigate climate change at regional, farm and vineyard level. The integrat - ed geospatial database (geodatabase) • Improvements to www.terraclim. • Application of regional climate su • High density temperature and rela extension. • Suitability analysis using vineyar T Calculated hourly threshold maps as hours above 18°C and 30°C for each growing season over five years (2015 - 2 is suitable for dynamic mapping, statistical interrogation, data mining, machine learning and climate change analyses. This is of great value to the producer in the Western Cape, due to the highly complex climate (ranging from semi-arid to mediterranean) and topography (mountainous to planar) and in the context of increased seasonal variability, understanding trends over space and time at farm and field level would contribute decision making. TerraClim solves th bility by providing highly detailed, up data at regional scales. This data is id current climatic and physical (terroi field, orchard or vineyard. The integ played through a user-friendly inte thereby addressing the limited acc information experienced by the agric The results from the TerraClim is novel and new to the Western Ca improved accuracy of temperature l decision making . Technical transfe to industry and potential user pay positive feedback. SOME KEY RESULTS IN 2020 IN • Finalisation of the central clima dures.

Late rainfall in the Breedekloof and Robertson areas created extraordinarily challenging growing conditions for most of the cover crop species in these areas, particularly at the site near Bonnievale where the treatments were sown in mid-June. The soil at this demo had to be disked twice before sowing. The performance of the rye and Braco white mustard treatments, however, provided a clear indication that these species ought to be considered where limited and late rainfall is a factor. The Bo-Langverwacht demo also demonstrated that medics and clover on the grapevine row has potential in this area as a 8 Swartland m dic mix Polymorpha medic (Cavalier), Barrel medic (Parabinga), Button medic (Bindaroo), Subterranean clover (Dalkeith), Balansa clover (Paradana) 12 kg/ha R1 200/ha Stand height: Low Stand d nsity: Poor Weed suppression: Fair to good S ed for t is medic/ clover mix was distributed on the grapevine row and did not receive irrigation.

weed management tool where irrigation after sowing is possible. Medics should be sown as early as possible and can be boosted with irrigation to promote germination. A well- established medic or medic/clover mix leaves provide an excellent cover of the vine row when growing and beneficial plant residue once it has died off. Thank you to Agricol, Winetech and the participating growers for their continued support for the Gen-Z cover crop demo programme. For more information, contact Emma Carkeek at emma@vinpro.co.za.

Thank you to Agricol, Winetech and the participating growers for their continued support for the Gen-Z cover crop demo programme.

Late rainfall in the Breedekloof and Robertson areas created extraordinarily challenging growing conditions for most of the cover crop species in these areas, particularly at the site near Bonnievale where the treatments were sown in mid-June. The soil at this demo had to be disked twice before sowing. The performance of the rye and Braco white mustard treatments, however, provided a clear indication that these species ought to be considered where limited and late rainfall is a factor. The Bo- Langverwacht demo also demonstrated that medics and clover on the grapevine row has potential in this area as a weedmanagement tool where irrigation after sowing is possible. Medics should be sown as early as possible and can be boosted with irrigation to promote germination. A well-established medic or medic/clover mix leaves provide an excellent cover of the vine rowwhen growing and beneficial plant residue once it has died off.

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WINELAND APRI L 2021

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