Uncategorized - Gordon Rajendram the soil scientist

If You Can’t Test, Then You Can’t Manage, Says Waikato Soil Scientist

Slow-release products or “suspension fertiliser technology” is the future for pasture growth in New Zealand, according to soil scientist Dr Gordon Rajendram. While fencing or planting trees along waterways to reduce phosphate loss is an expensive exercise, Dr Rajendram says more affordable methods exist. “The cheapest way to reduce P [phosphate] is to change your product from a highly soluble one to a less soluble one,” he says in disclosing five factors that drive pasture growth. Five years ago, at a soil seminar, Dr Rajendram says an elderly farmer had revealed to him the suspension method’s ability to apply 16 nutrients in one application. This technology ticks many boxes not only for pasture growth, but environmentally. The Waikato-based independent fertiliser consultant outlines five factors that drive pasture growth: 1/. Soil temperature at 10cm is a good indicator. A drop down to 5 – 6 degrees C stunts growth. 2/. Falling below 25% of soil moisture content slows growth. 3/. The pH (acidity) level and 13 key elements are required for plant growth. 4/. Soil that isn’t porous robs roots and microbes of air. 5/. Soil biology When testing the soil, he says it’s imperative to avoid dung and urine hotspot patches that can skew readings because of high nutrient levels. Animals excrete 66% of what they eat. “If you can’t test, then you can’t manage.” In a pasture of rye grass and clover, the former contributing to 19% of the protein in pasture and the latter 34%, as clover is a nitrogen fixer. “So, that means the more clover you grow, the more [nitrogen] you’re fixing for free,” he explains. Dr Rajendram says clover’s digestible quality yields more energy, compared with grasses. With clovers and most grasses ‘allergic’ to soil acidity, farmers need to monitor soil pH content to acquire 6.2- 6.5 soil pH levels. These soil pH levels are based on many factors with Irish farmers also recommended these ideal pH levels. Farmers must strike an “optimum” level to avoid low productivity but also not “overcook” to incur leaching costs. “In Waikato, you become a bit of a slave to phosphate but, in Canterbury, you have more potential to lose it,” Dr Rajendram reveals. “It’s hard-earned money you don’t want to lose.” April-to-October rain and drainage dictate the extent of leaching. Any nitrogen that plants fail to absorb drops incrementally by approximately a metre each year until it reaches aquifers and streams. Anions (negative ions), such as nitrate and sulphate, attract and hold cations (positive ions), such as calcium and magnesium, in aiding leaching. However, minute amounts of phosphate via runoff or leaching aren’t an economic issue, but an environmental one. Contact Gordon: Email: rajendram@xtra.co.nz Phone: 021 466 077 Facebook: https://www.facebook.com/GordonRajendramSoilScientist Contact MediaPA Phone: 0274 587 724 Email: phillip@mediapa.co.nz Website: www.mediapa.co.nz Facebook: www.facebook.com/MediaPA

If You Can’t Test, Then You Can’t Manage, Says Waikato Soil Scientist Read More »

Soil chemical and physical testing removes the guesswork out of farming says New Zealand’s leading expert in soil fertility, Hamilton-based Soil Scientist Dr Gordon Rajendram (PhD).

Waikato-based Soil Scientist Gordon Rajendram PhD is considered one of New Zealand’s experts in soil fertility. He is committed to helping New Zealand farmers get the most out of their soil so that their farm can work more proficiently, be sustainable while still increasing the farm profitability. Dr. Gordon Rajendram worked at AgResearch, Ruakura Research Centre, Hamilton. He has developed two field calibrated soil tests (N & S) which are used for agronomic advice in NZ and his work on leaching has been included in the Overseer nutrient model. Soils will continue to change over time, that’s why regular soil testing is crucial to the continued health and success of your farm says Hamilton-based leading Soil Scientist Dr Gordon Rajendram (PhD). Soil testing will showcase the mineral imbalances that may be affecting the health of your crops or livestock. Macroporosity is a measure of the proportion of large pores in the soil that provide the air supply to roots and microbes. A 10 % decrease in pasture production for every 1% decrease in microporosity below the critical level of 10 %. It’s the best soil physical field calibrated test for New Zealand and was developed by AgResearch in the late 1990s. Treading damage can cost loss in pasture production. “When soil structure is damaged, the infiltration, rate decreases and pores that are required for aeration and drainage are destroyed,” says Gordon. Other issues include ~80% decrease in worm populations, Increased runoff of water, sediment, faecal coliforms, phosphate and other nutrients plus Increased greenhouse gases. An ASC test (Anion Storage Capacity), previously known as P Retention, is a measure used to define the phosphorus (P) immobilisation potential of a soil. This will test the ability of the soil to hold on to phosphate and sulphur. An ASC test must be included with every sampled area to determine its level. “This is particularly valuable information when bearing in mind the use of phosphorus and sulphur fertilisers,” adds Gordon. Low ASC soils have minimal P binding sites. Once you have all the testing done, and have all the accurate information on what needs to go on your soil, the next step is to develop a fertiliser programme specific to each area or paddock. Fine particle or slow-release fertiliser is a great choice. Fine particle fertiliser has improved fertiliser use efficiency with lower spread rates required to get the most out of it. “Featuring a rapid uptake of needed nutrients, with fine particle fertiliser deficiencies can be rectified quickly due to the excellent foliar nutrient uptake,” adds Gordon. With the efficient application the proportion of nutrients can be varied. Not only that, it also has reduced environmental impact. You may not be able to change your soil type or the climate, but you can control the amount and type of phosphorus and sulphur that are applied to vulnerable areas. If you want to discover more about the benefits of soil testing can bring to your farm, then make sure you get the best in New Zealand, the soil scientist Dr Gordon Rajendram out to your rural farm today. With his BSc, MSc and a PhD, Gordon is one of the leading experts on laboratory and field measurement techniques for chemical, biological and physical properties. About The Soil Scientist Gordon is dedicated to helping all farmers get most out of their soil so that their farm can work more efficiently, be sustainable while improving the farm profitability. Contact Gordon: Email: rajendram@xtra.co.nz Phone: 021 466 077 Facebook: https://www.facebook.com/GordonRajendramSoilScientist Website: http://dev.gordonrajendramsoilscientist.co.nz LinkedIn: https://www.linkedin.com/company/the-soil-scientist Instagram: https://www.instagram.com/thesoilscientistnz/ Contact MediaPA: Phone: 0274 587 724 Email: phillip@mediapa.co.nz Website: www.mediapa.co.nz Facebook: www.facebook.com/MediaPA YouTube: www.youtube.com/user/TheMediaPA

Soil chemical and physical testing removes the guesswork out of farming says New Zealand’s leading expert in soil fertility, Hamilton-based Soil Scientist Dr Gordon Rajendram (PhD). Read More »

The importance of liming with New Zealand’s leading expert in soil fertility, Hamilton-based Soil Scientist Dr Gordon Rajendram (PhD).

Waikato-based Soil Scientist Gordon Rajendram PhD is considered one of New Zealand’s experts in soil fertility. He is committed to helping New Zealand farmers get the most out of their soil so that their farm can work more proficiently, be sustainable while still increasing the farm profitability. Dr. Gordon Rajendram worked at AgResearch, Ruakura Research Centre, Hamilton. He has developed two field calibrated soil tests (N & S) which are used for agronomic advice in NZ and his work on leaching has been included in the Overseer nutrient model. A lot of farms in New Zealand’s Hill Country have alarmingly low pH soil levels. There has been more emphasis on fertiliser at the expense of liming. However, both can be achieved within the farmers budget if a long-term plan is put in place says leading Hamilton-based Soil Scientist Dr Gordon Rajendram (PhD). Gordon says that generally pasture species do not like low pH soils as there is increased Aluminium in the soil solution which retards root growth, which in turn leads to less growth of herbage on top. MAF’s recommendation is for soil pH to be between 5.8 and 6.0 based on the dry matter production. “The ideal pH is around 6.2 if you take into account quality of feed, more clover growth, greater earth worms (which aerates the soil), more calcium in the diet, and phosphate less tightly held by the soil,” comments Gordon. Because of the cost of flying lime on Hill Country, a lot of farmers are put off from trying it. Lime is normally $20 – $35 per tonne, cartage is typically ~$20 -30 per tonne, but flying is ~$120/tonne. “There is not enough in the farmers’ budget when normal hill country farm fertiliser and lime budget is ~130/hectare/per year,” says Gordon. Normally it takes 1 tonne of lime to lift soil pH by 0.1 unit, but it much depends on the Cation exchange capacity (CEC) of the soil. A low CEC soil, such as a sandy soil, requires much less lime to lift pH by 0.1 unit. The problem with New Zealand farms is that farmers are not applying lime because of the above, so many soils are getting very acidic (< 5.5 pH), with soils getting down to as low as 5.0 pH. This has a significant detrimental impact on pasture production and clover growth, which ultimately leads to animal performance. The solution lies in having proper soil and pasture testing as without testing you cannot know what minerals needed to be added to your soil and in what amounts. Otherwise it becomes a guessing game. Expert advice is needed at the right time, with a plan to address the issue within the budget allocated. If these steps are taken, there is enough in the farmers budget to both lime and fertilise to reduce soil acidification. About The Soil Scientist Gordon is dedicated to helping all farmers get most out of their soil so that their farm can work more efficiently, be sustainable while improving the farm profitability. Contact Gordon: Email: rajendram@xtra.co.nz Phone: 021 466 077 Facebook: https://www.facebook.com/GordonRajendramSoilScientist Website: http://dev.gordonrajendramsoilscientist.co.nz LinkedIn: https://www.linkedin.com/company/the-soil-scientist Instagram: https://www.instagram.com/thesoilscientistnz/ Contact MediaPA: Phone: 0274 587 724 Email: phillip@mediapa.co.nz Website: www.mediapa.co.nz Facebook: www.facebook.com/MediaPA YouTube: www.youtube.com/user/TheMediaPA

The importance of liming with New Zealand’s leading expert in soil fertility, Hamilton-based Soil Scientist Dr Gordon Rajendram (PhD). Read More »