Information For Farmers

Transcription

1 Information For Farmers For Farmers Natal Aerial Spray utilizes many farm airstrips situated around our areas of operation. If an airstrip is further than 5km from the land to be sprayed, then we have to charge an additional fee to cover our costs. There is a list of airstrips on our website, if your lands are far away from any of these, then it may be worthwhile building your own airstrips. Please give us a call and we will gladly come and inspect any proposed sites. However the basic requirements are as follows : Well-Drained Obstacle Free(including rocks and holes) Surface of at least 900mx30m Each end clear of obstacles (tall trees, power lines) Should be aligned upslope, with maximum 2% cross fall Water on site is a bonus as it won t have to be tankered in Good maps are essential to ensure the correct field is sprayed. Google Earth Pro can be downloaded for free and is perfect for creating maps for this purpose. Please see the Google Earth Pro download link on the information page. The co-ordinates should be in the degrees and decimal minutes format(s29º55.87 E030º33.87 ). If there are sensitive crops adjacent to the land being sprayed then flags should be erected to mark the land. The file can be saved as a.kml file and ed to us. Below is a great example of a Google Earth map showing clearly the boundary of the field to be sprayed as well as the farm name:

2 Hand drawn maps can also still be used. To the left is a good example of a hand draw map: Joe Bloggs Additional features to include which neither of the maps above includes the marking of obstacles especially phone and electricity wires. Also adding the coordinates of the field on the map will make the pilots life easier having less paper to deal with in the cockpit. What is Aerial Application? Aerial application is the use of aircraft to seed, fertilize and treat crops with protective products to control weeds, insects and fungi. It is used on conventional cropland as well as biological control. Aerial application is also used to treat forest-land, rangeland and pastures for livestock. It is an important part of food, fiber and bio-fuel production. Benefits of Aerial Application Aerial application allows rapid treatment of large areas, 3-4 times faster than any other form of application, using turbine aircraft at 140mph. This is especially important when application is needed within a narrow timeframe. Pest resistance can be limited by aerial applications ability to treat in a precise manner. Aerial application can treat remote, hard to reach areas without causing any physical crop damage, where other methods cannot, due to surface water, wet soil, rolling terrain or dense plant foliage. Aerial application can treat orchards and late stage crops or dense plant foliage without causing any physical crop damage, soil compaction and without carrying disease from field to field as compared to ground rig operations. A reduction in soil compaction, reduced plant damage and less spreading of disease by aerial application results in higher yields, improved plant health, and if managed correctly, can absorb the cost of the aerial application, depending on yield and result, putting more money in your pocket. Equipment Natal Aerial Spray is currently operating one Ayres Turbo Thrush(ZS-PAF) equipped with a Pratt & Whitney PT6A Turbine engine, which couples high power and speed with extreme reliability. The Thrush has a 400Gal (1500lt) hopper for spraying which can cover up to 50Ha per load, depending on the water volume used. It can lift one tonne of granular fertilizer. The Thrush is equipped with a state of the art Satloc guidance system which is highly accurate when it comes to putting product down in the right place at the correct rate. We have top of the range loading equipment which includes 3 mixing rigs and a custom auger for loading fertilizer quickly and efficiently. We have 3 vehicles each carrying 1000lt of IP/JET A1 for the aircraft including one 4x4 to tow the auger for fertilizer and seeding applications. Our equipment is operated by 4 employees who are fully trained to load aircraft efficiently and safely.

3 Technical Information Spraying A major factor in the effectiveness of the chemical being applied to your crop is the droplets per square cm being used for application. Every chemical s label has a recommend volume that it should be applied at. These figures have been acquired through rigorous testing and many trials done by labs and when applied at the correct volume, will be most effective. Below is a label as an example: Take note that it requires application with a volume of 30-40lt and at this volume with the aircraft it should have droplets per square cm. It also recommends a VMD between microns and even states the height at which the aircraft should be flying above the crop. Water volume is a factor when applying any chemical and it is absolutely essential to spray as per the label & water volume requirement. If you have too high a water volume you will be saturating the crop which may lead to chemical run off and excess waste. Too low a volume could result in fine droplets causing excess drift and evaporation before the spray reaches the crop. Droplet coverage is the amount of droplets of spray per square cm, this can be changed in two ways: a finer spray with more small droplets per square cm which are prone to evaporation and drift, or, coarser spray with larger but less droplets per square cm resulting in saturation and chemical run off, which is pointless, large droplets may also bounce off the intended target. We must keep in mind that a wet plant is not necessarily the ideal situation, having the plant coated evenly with the correct amount and size of droplets, as per the label requirement, is ideal.

4 Droplet average size is referred to as VMD(Volume Median Diameter). The VMD refers to the midpoint droplet size(mean), where half of the volume of spray is made up of droplets smaller, and half of the volume is made up of droplets larger than the mean. For example a VMD of 300 microns indicates that half of the volume of spray is made up of droplets smaller than 300 microns and the other half is made up of droplets larger than 300 microns - human hair is 100 microns thick which is categorized as Very Fine in the droplet spectrum - droplets of this size will be highly susceptible to drift. There is a droplet size classification system that ranges droplets from extremely fine to ultracoarse. A product label may just recommend a droplet size such as coarse. Nozzle selection and pressure are then based on the nozzle manufacturer s droplet size category chart. Drift & Evaportaion Normal Application Pre-emergent herbicides The fixed wing aircraft normally use a spray that has a VMD ranging from microns, which is classified as a medium spray, with reduced risk of drift. This spray quality is advantageous due to it being fine enough to have high droplet coverage without it being too fine to drift, minimizing drift and evaporation. The droplet size is always altered to best suit the product/label requirement, ensuring that the product is applied as it has been designed to be. Chemical applied via aerial application must be applied as per the label for them to be effective, reducing water volumes is not recommended, it will affect the result. So in the case of the label above it should be applied at a minimum volume of 30l/Ha. Due to the size of aircraft hoppers they should then all be able to spray a certain number of hectares per load as follows if applied at the correct water volume/as per label : Turbo Thrush ±1500 litres ±50Ha Cessna Agwagon ±660 litres ±22ha Piper Pawnee ±450 litres ±16Ha Robinson R44 ±300 litres ±10Ha Robinson R22 ±120 litres ±4Ha Microlight ±90 litres ±3Ha

5 The only way any of the aircraft above will spray more hectares is by going off label and spraying with lower water volumes possibly leading to large amounts of drift and evaporation, resulting in the product being less effective, which could lead to drift damage and/or resistance. When it comes to aerial application, there are factors that the pilot needs to take into account to ensure that there is good coverage and minimum striping. One of these factors is flying height, the aircraft should be flown at 3-4 meters to ensure that the swath closes underneath the aircraft and that it opens on the outsides of the spray pattern. Flying too low will result in uneven coverage, as well as the spray being forced up by ground effect, increasing drift potential. The nozzles should also be placed within the inner 65%-75% of the wingspan to reduce the spray entering the wingtip vortices. 3-4 meters Humidity plays a role in effective application. The humidity should not be below 45%. Wind plays a larger role when it comes to dealing with spray drift. Spraying should be ceased when the wind speed exceeds 15km/h. Air stability plays a role as well. Air stability can be described as the up and down draughts in the atmosphere or the lack thereof. Spraying should not be continued under an apparent temperature inversion, as it may lead to the following: Reduced efficacy due to suspension and evaporation of small droplets in the air (inadequate coverage). Damage to other sensitive crops and/or non-target areas through drifting of the suspended spray cloud away from the target field. Natal Aerial spray carry mini weather stations on board so that we can constantly monitor the temperature and the humidity. If you would like to check the weather forecast for your area just click the Windguru logo at the bottom of our website and look for your nearest weather station. Looks like this:

6 Fertilizer & Seeding Application Aerial fertilizer application is a great tool to use because granular fertilizer can be applied swiftly to a crop without disrupting or damage the field due to compaction. Timing can be key and by using an aerial applicator, fertilizer can be applied at the right stage, at the correct rate for the crop - The aircraft can change its setup from spraying to fertilizer application within a few minutes. To apply fertilizer aerially we use a venturi spreader. The spreader is mounted on the underside of the aircraft to the gate box of the hopper. As the adjustable gate of the gate box opens, material from the hopper falls into the venturi spreader, which is then distributed though the venturi spreader by airflow. The more the gate opens the higher the rate at which it is applied. See below a diagram of the venturi hopper installation on the aircraft. There are many advantages to applying fertilizer by air: No theft of fertilizer, as it is all applied swiftly to the crop, from one loading point. Accurate application in terms of rate per hectare and placement. Correct timing; we are able to apply around 250Ha a day, weather dependent. Variable rate; we can apply from 50kg/ha to 650kg/Ha (prices vary according to rate). No trampling of your crop resulting in a loss of yield and spread of disease. The spray height for the application of fertilizer is between 6-12 meters. Swath width and application rates work hand in hand with one another, a higher application rate would result in a smaller swath width due to the overlap factor. With the Ayres Turbo Thrush we can lift 1 ton of granular fertilizer which at 50kgs a bag equates to 20 bags of fertilizer a load. We supply an auger to load fertilizer but we do require labour supplied by the farmer to load the fertilizer into the auger. Fert can be applied in higher wind conditions than spraying, depending on the airstrip and terrain. Aerial seeding of cover crops into existing mature maize before harvest allows for early establishment of the cover crops. Cover crops help farmers to, control erosion, retain/recycle nutrients, build organic matter to improve soil health, improve moisture availability and to break up disease and insect cycles. Using aircraft to plant your cover crop means that you can seed 1 ½ months earlier allowing the grass to establish well before the first frosts.

7 As you can see in the images on the right the cover crop that was seeded by aircraft had a lot more time to establish than the seed that was planted by ground equipment. For aerial seeding we use the same venturi spreader as used for fertilizer. The rate can be adjusted from 10-50kg/Ha.