John Deere HarvestLab 3000 (calibration model LKS  09/17)

All recorded nutrient values, application rates and application amounts are displayed on the fully integrated GS3 2630, Gen4 4600 CommandCenter and the 4640 Universal Display, and at the same time up to four different values are site specific recorded.
Using the wireless Data transfer (WDT) from John Deere the documented data can immediately transmitted via mobile for data
storage, further analysis or common use with customers or agronomic advisers to the John Deere operations center.

Advantages of the HarvestLab 3000 Near Infrared Technology:

• High accuracy through multiple readings
• Measurement during appli­cation
• Analysis of the whole substrate instead of just single sampling
• Simultaneous analysis of several ingredients
• Non-destructive measurement
• Application according to target rate and marginal rate or according to prescription map
• Adjustment of nutrient delivery rate by automatic speed and flow rate control

Method of near-infrared measurement (see picture 2)

A light source (A) projects a beam directly onto the substrate or manure passing the lens of the sensor (B). Parts of the light are absorbed and the rest of the light is reflected. The reflected portion is detected and with a subsequent calculation the HarvestLab 3000 Sensor (C) can determine the dry matter content and the ingredient values.

The manufacturer specifies the measurement ranges listed in Table 2 for the calibration model used in the system.

Table 2: Measuring range JOHN DEERE HarvestLab 3000 with calibration model LKS 09/17

The scope in the DLG Test is limited on substrates, which are described as manure according to the German Fertilizer Act, so on cattle manure, pig manure, mixed manure from cattle and pig manure, and liquid digestate from cattle or pig manure with renewable raw materials.

The DLG test is available for the measurement of the following ingredients:

• Dry matter content (DM in % Weight.)
• Total Nitrogen amount (N_Total in kg/m³)
• Ammonium nitrogen amount (NH₄­N in kg/m³)
• Phosphate content (Phosphorous Pentoxide; P₂O₅ in kg/m³)
• Potassium (Potassium Oxide; K₂O in kg/m³)

In order to cover a wide range of applications, the test attempts to use a diverse spectrum for each type of substrate:

• Cattle manure: 4 % DM – 9 % DM, where possible from dairy cows and fattened cattles 
• Pig manure: 2 % DM – 7 % DM, where possible from sow-keeping + fattened pigs
• Mixed manure from cattle and pig manure: concentration series as follows 10 %cattle : 90 %pig / 30 %cattle : 70 %pig / 50 %cattle : 50 %pig / 70 %cattle : 30 %pig / 90 %cattle : 10 %pig
• Liquid digestate from cattle or pig manure with renewable raw materials: 5 % DM – 8 % DM

The DLG approval can be awarded for individual types of manure and individual ingredients. To get a DLG recognition, at least the requirements for the measurement of the total nitrogen content (N_Total) need to be met. When the requirements for the measurement of the total nitrogen content are met, other ingredients can be freely chosen.

The process

Depending on each type of manure (cattle manure, pig manure, mixed manure from cattle and pig manure, liquid digestate from cattle or pig manure with renewable raw materials) five individual and as diverse as possible samples are measured and sampled on different farms. For this purpose, a subset of 3 m³ to 5 m³ is pumped from the previously stirred slurry storage in an intermediate tank. 

At the intermediate tank, a pump and a common piping system are installed. On the piping system one or more sensors to be tested and a bypass for sampling are attached. If necessary, a flow meter for the control of flow rates can be attached (see figure 3).

In a preliminary phase the collected manure is intensively homogenized in the intermediate tank by continuous circulation in a closed circuit.

Following this preliminary phase, the measured values of the sensor are documented. Afterwards subsamples for the reference analyses are then taken via the bypass while maintaining inflation around the closed circuit. In order to determine any possible influence on the sensor values, subsequently the flow velocity is varied and the measured values are re-documented.

The manure samples are clearly marked, frozen and stored frozen. Five suitable laboratories are commissioned with the reference analysis. Each laboratory receives partial samples of each manure. The analyses in the laboratory must be carried out using officially recognized methods, preferably wet-chemical methods.

For each manure and each ingredient, the arithmetic mean value is calculated as a reference value from the laboratory results. The assessment of accuracy is based on the relative deviations from the sensor value in comparison with the reference value.