Do you want to learn more about managing our most precious resource for food production? Do you want to see why and how a soil sample should be taken?
LandWISE will be holding a FREE to attend soils workshop in Hastings on the 20th of August. All are welcome to join us for a presentation on the following topics:
Understanding soil tests – how to interpret values
Following trends in soil test values e.g. Olsen P, bringing values back to the ‘middle’/optimum
Using soil tests as the basis for a fertiliser plan
An introduction to N-Test Strips and VSA
Interpreting fertiliser recommendations from the new Nutrient Management for Vegetable Crops book (Reid and Morton, 2019) and current fertiliser guidelines for Pipfruit and Grapes.
This will be followed by a short field visit to demonstrate and discuss how to take a representative soil sample from a paddock, as well as using N-Test Strips to understand the amount of plant-available N in soil.
DETAILS
Hastings, HB
Tuesday 20th August 1:00pm, Green Shed, 21 Ruahapia Road
This event is presented as part of “Future Proofing Vegetable Production”, a Sustainable Farming Fund project supported by government, industry and farmers.
We’re not quite sure what to call the job: science manager, extensionist, project manager, consultant? We know it offers diverse activities and needs excellent communication skills and practical knowledge of horticulture and technology.
We are looking for someone to help identify and lead research projects and extension activities across a variety of issues and regions. For the right person, this is a role with considerable potential to grow.
This will be a Page Bloomer Associates appointment. They provide our science, management and support services while having addditional private consultancy activities. Working closely together, we know they share our passion for sustainable land and water management.
Since the dawn of the new millennium we’ve been providing progressive, pragmatic and independent services through projects and consultancy. A key feature of our work is close collaboration with end users, researchers and developers. We talk about “linking thinking from the farm out”.
The role includes engaging with growers, industry and researchers to identify opportunities to review practices and integrate new technologies to create sustainable cropping systems. The appointee will develop and manage projects and support services that support economically and environmentally sustainable primary production.
If you know someone with passion for smarter farming who wants a key role in a small dedicated organisation, Page Bloomer Associates would like to chat with them!
Do we really know why we farm as we do? Or are we constrained in ways we just don’t see?
Often our current practices have evolved over a very long time – thousands of years of human history, decades of technology developments. Remember the space shuttle and the horse’s rear? We’ve long forgotten some of the reasons behind what we do, so maybe it is time for a reset!
Brad Bernhard was born and raised on his family’s hog and grain farm in northern Illinois. We were introduced to him via a fascinating webinar that included the benefits of applying liquid fertiliser to create high N concentration directly in the plant’s rooting zone.
Brad earned his Master’s degree under the advisement of Dr. Fred Below in the Crop Physiology Laboratory studying the use of innovated foliar micronutrient sources in high yielding corn and soybean production systems.
Recently, Brad completed his Ph.D. degree in Crop Sciences focusing on in-season fertility using different fertilizer sources and application methods. In addition, he investigated ways to manage higher corn planting densities using narrower row spacings along with characterizing hybrids for use in these more intensive cropping systems.
Y-drops; a new way to apply nitrogen to row crops (Brad Bernhard image)
We think this approach has great potential for a wider range of crops, including winter vegetables, but have no doubts that it is not a case of a simple switch. We asked Brad to join speakers at LandWISE 2019 to share his experiences and (perhaps) warn us of some of the fishhooks he encountered along the way.
One of the four key areas within the Future Proofing Vegetable Production project aims to improve the accuracy of fertiliser applied. This work is part of the MPI Sustainable Farming Fund “Future Proofing Vegetable Production” project, co-funded by Horizons Regional Council, Potatoes NZ, Gisborne District Council, Ballance AgriNutrients and LandWISE.
Growers were invited to participate in having their equipment assessed. Equipment was tested with growers in both Horowhenua and Gisborne. Ten fertiliser applicators have been assessed through working with eight growers. Multiple settings or products were tested for some equipment.
In-Field Fertiliser Applicator Calibration Test
Performance
assessment of fertiliser application equipment provides information on actual
rates applied and the evenness of application. Ensuring that fertiliser is
applied evenly minimises the risk of leaching if over application occurs, or
the risk of yield penalties if under application occurs where nutrient
availability is limiting plant growth. Growers were confident their equipment
was spreading evenly, however the assessment results show there is room for
improvement.
Fertiliser
application equipment measured can be split into two main categories:
Direct placement machines (banders, side dressers and planters)
Figure 1: Examples of fertiliser application methods commonly used in vegetable growing systems: broadcast (left), potato planter (centre), and modified into 2 row bander (right)
Different methodologies are appropriate for broadcast versus direct placement equipment.
Broadcast fertiliser spreaders
were tested according to the FertSpread Protocol: see www.fertspread.nz
Power take off driven placement
equipment (banders or adapted oscillating spouts) were assessed by placing
buckets under the outlets and collecting fertiliser for a measured time (~30 –
60 Seconds). By determining travel speed the application rate can be
calculated.
Ground driven equipment (most
side dressers and planters) were assessed by collecting fertiliser from outlets
over a set distance in-field or from 20-wheel rotations in static testing.
Tests were repeated twice, however where results between tests appeared quite different, the test was repeated up to six times. For some machines multiple settings or fertiliser products were tested.
Direct placement machines were assessed using a calibration calculator that has been developed over the period of testing this equipment as there is currently no industry accepted assessment calculator available.
The draft fertiliser calibration calculator for the assessment of direct
application machines is included in the supporting documentation. This
spreadsheet calculates and reports a wide range of statistics to assess
performance.
The application variability of the direct placement equipment tested varied quite markedly; from 0.4% CV to 26.4% CV. A summary of the test results for direct application equipment is provided in Table 1.
Table 1
All but one of the machines tested are within the SpreadMark accepted performance for broadcast spreaders applying nitrogen-based fertilisers.
The actual rates of fertiliser applied varied from the target rates. In one case the actual average rate applied was 48% of the target rate, the greatest over application was 152% of the target rate.
Fewer broadcast spreaders were assessed as direct placement machines are more commonly used in intensive vegetable production systems. Table 2 provides a summary of the two broadcast spreaders assessed.
Table 2
Figure 2 gives a snapshot of part of the report produced through the FertSpread website. In this example, if the grower reduced their bout width from 22.5m to 19m, the machine performance would be within the acceptable level for nitrogen and non-nitrogen fertilisers.
Assessments have been
completed on a range of fertiliser application equipment in both Levin and
Gisborne. Most of the equipment tested has been direct application (banders,
planters and side dressers), rather than broadcast spreaders. Fertiliser applications for vegetable production are predominantly
applied as banded strips along the bed or scarified during planting or as a
side dressing. There is currently no accepted protocol for the assessment of
this type of equipment.
To enable the
assessments to be completed within the project, a draft protocol and fertiliser
calibration calculator for direct applicators has been developed and is being
refined. This is currently in an Excel spreadsheet which has been developed as
we have been testing equipment. The number of tests required and the statistical
analysis to report the suggested three key indicators is still to be discussed
and agreed upon. This concept and draft calculator will be taken to the annual
Fertiliser and Lime Research Centre conference in February 2019 for advice from
leading experts. The acceptable level of equipment performance and report
outputs provided to growers will be discussed.
It is currently
accepted for broadcast fertiliser spreaders that the coefficient of variation,
CV, should not exceed 15% for nitrogen fertilisers and 25% for non-nitrogen
fertilisers. The method of calibrating fertiliser rates applied ‘through the
spout’ to achieve target rates are accepted, however a different statistical
analysis is required for an assessment to be completed and best practice or
acceptable levels of variation need to be defined. It is suggested that a CV of
15% for nitrogen or even non-nitrogen fertilisers is well below the capability
of these direct placement applicators. Machinery in good working order should
achieve a CV of much lower than this, but an acceptable CV is not currently
defined.
This has opened discussion around how the acceptable CV is determined and if this is applicable in vegetable production systems. Our understanding is that accepted variance is based largely on pasture value and response curves, we query what values are appropriate for high value vegetable crops. Excess fertiliser increases leaching risk, insufficient fertiliser can make a crop unsaleable through quality loss. This is another area that it is felt important and worth further investigation.
The results of the
tests carried out on direct placement equipment highlighted several key areas
to address:
The target rate is not often achieved, the
results showed machines are both over and underapplying, which have
implications for leaching risk and potential marketable yield penalties or
decrease nutrient use efficiency.
In some cases, the outlets are not applying
fertiliser at equal rates. The cause of this is different for each machine. However,
the growers were keen to investigate why one outlet was applying a lower rate.
In one case the grower was able to fix the equipment and significantly reduce
the variation between outlets.
One machine resulted in different rates being
applied in each test. This is a greater concern for older equipment that is
worn and manually operated hoppers.
The amount of the fertiliser in the hopper appeared
to affect the rate of fertiliser applied. This suggests that as the hopper
empties that rate applied to the beds decreases. This also appeared to change
significantly with the bulk density of the fertiliser product. More testing is required
to investigate this further. There may be a minimum amount of fertiliser
(product/bulk density dependent) required to be in the hopper to achieve an
even application.
The interest and
engagement of growers through testing their equipment has built awareness. Once
a protocol is developed, the spreadsheet will then be developed into a tool for
growers. Prior to next season, workshops demonstrating how to calibrate
equipment, use the tool and interpret the report will be run in Gisborne and
Levin, with the possibility of visiting additional regions. Conversations with
growers during visits have shown there is good support for an event.
Broadcast
spreaders are less commonly used, and only two-disc spreaders were assessed. The
results showed that at the current bout width used neither machine was
achieving an acceptable CV for nitrogen fertilisers. One of the two was on the
limit of acceptable for non-nitrogen fertiliser products. This suggests that
the growers need to change either settings and/or bout width to achieve an
acceptable CV.
Reports are generated for all equipment we tested and distributed to growers. Some growers have requested that we re-test their equipment after they have made adjustments or prior to next season.
Do you want to learn more about managing our most precious resource for food production? Do you want to see why and how a soil sample should be taken?
