NUUSBRIEF / NEWSLETTER

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1 16/06/2015 ISSUE 35 UITGAWE 35 NUUSBRIEF / NEWSLETTER Inside this issue: Inhoud: Groentoer 2 30 jaar No-till Nuus/News Meganiese versteuring 8 Hallo Almal Die seisoen het toe darem uiteindelik begin. Die suidkaap het baie swaarder neerslae ervaar as die Swartland gedurende die stormweer. Ons is dankbaar dat almal darem nou aan die gang is. In die volgende uitgawe van die nuusbrief sal ek die program vir die bewarings konferensie week deurgee asook die inligting waar om te bespreek en jou plek vas te maak. Ons gaan vanjaar 4 sprekers hê, 2 uit Suid-Australië en twee plaaslike sprekers. Daar gaan ook genoeg tyd ingebou word in die program vir n lekker vraag-en-antwoord sessie. Ons beplan ook n paar verrassings vir die konferensie week. Upcoming farmers days and events: Tygerhoek groentoer 23 Julie Swellendam groentoer 6 Augustus Swartland Groentoer 20 Augustus Riversdal Boeredag 26 Augustus Sterkte aan almal. Groete van huis tot huis Johann Strauss The url to the Science of soil health Channel videos

2 P a ge 2 Groentoer Tygerhoek Plek: Tygerhoek Navorsingsplaas Datum: 23 Julie 2015 Tyd: 09h30 vir 10h00 Agenda: 09h30 tot 10h00: Kom bymekaar by kantore vir koffie 10h00 12h00: Besoek winter dekgewas proewe 12h00 13h00: Verversings Besoek planter demo s kamp 3 Besoek wisselbou kamp waar 2 stoppelbehandelings toegepas is. RSVP asb teen die 20ste Julie 2015 om getalle vir verversings te bereken. Johann Strauss: johannst@elsenburg.com MG Lötter: devlei@whal .co.za

3 P a ge 3 Green tour Tygerhoek Place: Tygerhoek Research farm Date: 23 July 2015 Time: 09h30 for 10h00 Agenda: 09h30 10h00: gather at offices for coffee 10h00 12h00: Visit winter cover crop trials 12h00 13h00: Verversings Visit planter demo camp 3 Visit crop rotation camp where 2 residue treatments were done to ease planting effort RSVP by 20 July 2015 for fereshment purposes Johann Strauss: johannst@elsenburg.com MG Lötter: devlei@whal .co.za

4 P a ge 4 30 Years of No-Tilling Yields Healthier Soils, Better Planting Marshall Alford's decades-long experiences with cover crops and no-till corn and soybeans have helped him protect and preserve the soil, improve crop emergence and boost his fertility program. By Laura Allen posted on March 20, 2015 Posted in Cover Crops, Equipment, Soil Health Growing up on his family s farm, Marshall Alford noticed the tobacco and corn they grew on the back furrow always raised the best crop. It was ground that was never plowed and never washed. Years later on his own farm, he started telling landlords he was interested in trying no-till, but didn t think any of them would go for it. This one will, one landlord told him. So in 1985, Alford no-tilled corn on part of the landlord s field, which happened to be frequently wet and tough to raise corn on. But the crop emerged and was taller than the rest of the crop. When we combined it, it didn t take long to see the difference, Alford says. I thought, We re just going to go 100% next year. So we started and kept on. Protecting Soil When Alford and his wife, Darla, moved to their corn and soybean farm in Moores Hill, Ind., in 1969, the ground was white when it was dry. The land had been a dairy farm up until 1963, and in the 6 years that followed it was rented to farmers who planted soybeans on it every year, causing the soil to lose all of its carbon, Alford says. But years of no-tilling and cover cropping on their now 950 acres have made the soil darker, carbon levels are up and organic-matter levels are around 3-4%. Alford first started using cover crops by having a helicopter aerial seed winter wheat into his soybean crop. He chose winter wheat because it was cheap, easy and reliable.

5 P a ge 5 The soybean ground down here, if you don t put something on it, it ll wash badly in the spring. I don t want the water running off looking dirty, Alford says. We started putting something down to hold the soil, and that was the cheapest way we could go. One time he had a wet season and lost about 100 acres of soybeans because the winter wheat grew too tall and he couldn t combine the soybeans, so now Alford only seeds the cover crop after soybean harvest. He seeds winter wheat or cereal rye at 1-1½ bushels per acre, and sometimes adds 3-5 pounds of crimson clover with it to provide a little nitrogen (N) for the following corn crop. When it s time to terminate the cover, he prefers to wait until after he s planted the corn. This ground s wet, he explains. If I ve got a cover crop like winter wheat or cereal rye in the spring, I plant first and let it dry the ground out. We can have a lot of rain, but that growing cover crop helps dry the ground. He adds that if he were to terminate the cover crop first, he may not be able to get to planting in time. Alford aims to spray the cover crop within a half day of planting, typically using Gramoxone and Lumax together. Another cover crop species Alford s used is daikon radish. He recalls seeding the radishes on a field that previously had cattle on it and not being able to tell compaction from the livestock ever existed. He did learn, however, that he seeded them too heavily about 9 pounds per acre. THREE DECADES OF NO-TILL. Growing up, Marshall Alford noticed the best corn and tobacco raised on his family s farm was in ground that was never plowed and never washed. After no-tilling corn on part of a landlord s field in 1985, he went 100% the next year and never looked back. Today, his tight silt-loam soils are mellow, darker in color and have organic-matter levels of 3-4%. They were too small, Alford says. Maybe the size of your thumb or a little bigger, but there was a lot of them. Now I think 3 pounds would be better with cereal rye or something else.

6 P a ge 6 Spoon-Fed Fertility In addition to holding and improving the soil, cover crops play a role in Alford s fertility program by improving soil ph levels and reducing the amount of fertilizer he needs. He s also using covers to apply fertilizer. Before he seeds his winter wheat in the fall, he blends it with potash and diammonium phosphate (DAP). That way I can spoon-feed the ground with nutrients instead of putting a whole bunch on at one time, Alford says. The amount of potash and DAP he applies depends on how the season went, what the weather s like and the field he s on. He says last year he applied 100 pounds of potash with the winter wheat, but the year before it was 75 pounds each of potash and DAP with wheat and crimson clover. After applying the potash-dap-wheat mix, he applies the rest of his fertilizer during planting and sidedressing. Using his Kinze 3600 planter, he applies 7 gallons of per acre, as well as zinc and orthophosphate (which has a low-salt index) directly in the seed furrow. He also applies in a 3-by-2-inch band a combination of 9 gallons of 28% liquid N and a gallon of per acre. Since there are four tanks on the planter, he uses the inside tanks for the N and , while the outside tanks are for the starter fertilizer. This allows him to maintain an equal weight on both sides of the planter as he goes through the field. In his final fertility application, he applies more N and during sidedressing. He says the provides additional potash, while the sulfur helps hold the N. Alford typically applies 150 pounds of N throughout the season. He also knows how much fertilizer goes into one bushel, so he can calculate how much fertilizer he s removed based on yields. For corn and soybeans, 2014 yields ranged from bushels and bushels per acre, respectively. He aims to maintain the nutrients he s removed plus a little extra. Planting Deep Years of continuous no-till and cover crops have mellowed Alford s Clermont soils a deep, poorly drained silt loam which has improved his planting results. His Kinze planter has floating Martin row cleaners with depth bands, Keeton Seed Firmers and Martin spiked closing wheels, which Alford runs with little to no down pressure due to his changing soil conditions. He s learned that a deeper planting depth is better on his farm. If you put seed in the ground a little deeper, you have a better chance of the plants coming up more evenly, he explains. If you ve got it on top of the ground, you ve got those little dry spots, and plants in those places won t come up as quick. You ve got to put it in the ground where there s moisture. Alford thinks the spiked closing wheels help achieve even emergence.

7 P a ge 7 If you dig down after you ve used the spiked closing wheels, that first ½ inch or so is kind of pressed, but the rest of it s laying on top, so the seed can come right out of the ground, he says. Agri-SC, a soil conditioner that Alford has used since the early 1970s, has also helped his planting operations because it doesn t allow the tight soils to crust like they used to. It seems like it lets the water through, just like no-till does. After you get a big rain, the soil stays moist, but the water percolates better, he says. He s noticed the difference between his planting population and harvest population isn t as much as it used to be, and he thinks the deeper planting depth has helped that. Working With Nature Alford also thinks the Agri-SC is helping his herbicides do a better job, because it takes the beading out of the water and allows the chemistries to spread out across the soil like they re supposed to, he says. He applies the Agri-SC at 4 ounces per acre with his pre-emergence herbicide. Alford also keeps an eye on his soil ph to make sure the herbicides can work properly. He used to have a cocklebur problem in a couple of field areas, but after he raised the ph the herbicides worked better. Alford only raises non-gmo premium corn and soybeans, so his herbicide options are limited. He makes sure to rotate chemistries so resistance issues don t occur. But whenever possible, Alford prefers to let Mother Nature handle any pests and diseases that his crops may be battling. Aside from seed treatments, he avoids using products that may harm the natural critters and processes that are working for him, such as insecticides and fungicides. He hasn t faced a problem in recent years. My beneficial insects protect me against the ones that we don t need, he says. It seems to me the less spraying I do, the better off I am.

8 P a ge 8 MEGANIESE VERSTEURING VAN GRONDE IN BEWARINGSBOERDERY my ervaring Deur Charl van Rooyen Spesialis Voorligter Wes-Kaapse Departement van Landbou Wanneer is grondbewerking geregverdig? Of beter gestel wanneer behoort die profiel van gronde versteur te word om winsmaksimering oor die langtermyn te bewerkstellig. Uit n bewarings oogpunt kan die prosedure beskryf word as nie toelaatbaar, maar met uitsonderings. Wat is dus die uitsonderings wat aangespreek behoort te word?: Ploegbanke geskep deur vorige implimente en aksies op gronde Probleme wat a.g.v manokultuur geskep is bv. Witsykantkewer in lusern lande wat te lank gelê het Kompaksie deur die onoordeelkundige beweiding van plaasdiere. Dit is altyd belangrik om die problem aan te spreek en nie die simptome te behandel nie. Die bestaan van harde lae in gronde mag ook die gevolg wees van chemiese probleme in die grond wat op n spesifieke diepte voorkom. Om hierdie probleem meganies te probeer oplos deur diepbewerking met n tandimpliment helling af het meestal teleurstellende gevolge. Ten eerste kom die probleem gewoonlik in die droër dele van die Wes-Kaap voor, waar reënval nie hoog genoeg is om die soute uit te was nie. Die maak van afsnydreins van ongeveer 1m diep, help gewoonlik, en meer as dit die koste is laer. Die vereiste is egter dat n sivieler ingenieurstegnikus die hele plaas se water afloopbeheer moet beplan. Dit behels die paaie, drade en kampgroottes wat aangepas moet word by planter en spuit wydtes. Slote behoort sonder walle te wees behalwe as dit dien as n draadposisie of aanduiding van die dreinering vir manne wat in die nag plant. Die val van so n dreineringsloot sal ongeveer 1:100 wees om voldoende vloei te verseker. Begin altyd by die afleibaan waarin die dreinering uitmond. Maak seker dat dit al die water sal kan hanteer, die tegnici het formules wat die raai uit die proses haal. Hierdie tipe dreinering word verkies bo die rif en voortipe waar die hele grondprofiel van n land versteur word en dus elke 16 of 20m n dreinerings gebied geskop word. Effektief word die potensiaal slegs op 75% van die grond verbeter. Dit is voorts belangrik om die navorsing wat in Suid-Amerika gedoen is toe te pas waar kalk bo-op toegedien word en met natuurlike prosesse in die grond in beweg. Hierdie navorsing is herhaal deur die WKDL en soortgelyke resultate is behaal. Bekalking moet altyd geskied volgens n verteenwoordigende grond monster en aangepas word met onderverdeling. Aangesien bekalking die ph van die grond verander moet gelet word op die moontlike te korte wat geiniseer kan word, bv. Mangaan (mn) wat teen n 2 ton kalktoediening per hektaar onopneembaar raak vir plante.

9 P a ge 9 Gebruik Mulder se kaart en Turog se tabel as riglyne om mootnlike probleme te voorkom. Die neem van totale plantonledings om moontlike tekorte reg te stel word aanbeveel bo slegs blaarontledings, van eenjarige gewasse. Die probleem van ronde kaal bolle is algemeen in lusernstande van veral die nuwe lusernkultivars. Dit kan toegeskryf word aan die teenwoordigheid van witsykant kewers in die grond. Die oplossing van die probleem is om die land dan diep om te ploeg met n skaar ploeg en die larwes aan die son bloot te stel en dan weer voor te begin met alles wat tot dan met bewaringbewerkstellig is, terug gerol na nul. Onthou dat monokultuur ook in n graan/lusern sisteem teenwoordig is as die lusern te lank lê. Navorsing is nodig om te bepaal of die insaai van n somer gewas die probleem kan oplos. Die probleem kan chemies opgelos word maar die resultaat na n plaagdoder soos aldikarb is net so skadelik op die grondlewe. Die opheffing van kompaksie in die grond deur bewerking is die oorblyfsel en bewys van ons Europese oorsprong. As daar n onverklaarbare probleem in n land is gryp ons terug na die trekker en ploeg dit reg. Gelukkig is die diesel prys nou aan bewarings boerdery se kant. Wanneer moet grond diep gerip, banke gebreek, klippe uitgehaal word? Dit is gewoonlik makliker om te sê wanneer is dit onnodig. In die rooi Pools gronde met heuweltjies mag dit voordelig wees om sout uit gronde te dreineer, maar die swak struktuur van die gronde wat na reën weer saamsmelt sal die bewerking op n gereelde basis vereis. Dit sal ook die grondlewe op die heuweltjies in die bo grond vernietig. n Moontlike oplossing in so n situasie sal wees om deur opmeting n dreineringsplaat tussen die heuweltjies na n laer punt te maak. Bly net prakties met die slote en moenie op n kaart werk nie, doen die finale besluit met n opmeting op die land. Op gronde wat dispersief is, baat dit nie om diep te werk nie aangesien die voordele van die bewerking nie op die langtermyn voordele inhou nie. By dispersief bedoel om gronde wat strukureël onstabiel is. Die grond aggregate destabiliseer sodra dit versadig raak met water omdat die individuele klei partikels oplos in die water. Klei partikels het n negatiewe lading op hul oppervlakte in hierdie lading word n balans gehou deur positief gelaaide katione soos Ca#, Mg#, K+ en Na+. Indien die verhouding van natrium tot onder katione hoog is word klei partikels nie sterk gebind nie en die grondageregate destabiliseer makliker sodra die grond versadig raak met water. Dit kan dan lei tot verhoogde afloop en gevolglike verseeling of korsvorming. Dit lei dan tot laer suurstof inhoude van die tipe gronde. In die ondergrond gebeur dieselfde proses en dus het die grond laer suurstof inhoude wat groei en opbrengs beinvloed. Water beweging is stadig en gronde bly lank versuip. In die Wes-Kaap is fyn tekstuur in die B-horison n verdere probleem. Swak struktuur van gronde is gewoonlik meer prominent in gronde met meer as 10% klein en of fyn matreriaal in die B-horison. Die oplossing van die probleem van sulke gronde lê gewoonlik in die toepassing van n goeie deklaag op die grond, asook die produksie van gewasse met n hoë getal eenjarige wortels soos koring, gars en hawer. Indien moontlik kan n geharde somer gewas soos sorghum gevestig word om die gronde in die droë somer te beskerm teen ontblooting.

10 P a ge 10 WEBTUISTE WEBSITE Die webtuiste is na opdatering en bietjie skaafwerk terug aanlyn en kan daar nou video s van vorige kongresse ook gesien word. Die vra en antwoord seksie is ook verbeter sodat vinnger antwoorde deurgegee kan word. The website is back online, following some much needed repairs and updating. Video s of previous conferences are also now available and the question and answer section has been improved so that reposnes can be given much quicker.