Great Plains 1520P Operator Manual - Manual (Page 40)

1510P and 1520P
118-732M 5/6/2010
38
Checking Singulated Seeding Rate
The seed charts are based on cleaned and sized
seed. Extreme seed size variations, foreign mate-
rial and tire pressure will affect the seeding rate.
Check the seed population rate as described
below.
1. Adjust the planting depth to a shallow setting.
2. Plant at the desired planting speed for a short
distance.
3. Using the table below, determine how many
rows need to be counted.
4. Measure a distance of 17ft 5in- in the planted
area. If 20-inch row spacing is being used,
measure a distance of 26ft 2in- in the planted
area.
5. Count the number of seeds, in the appropri-
ate number of rows, over the distance mea-
sured.
6. Multiply the number of seeds counted by 200
if measuring for 1/200 acre or 1,000 if mea-
suring for 1/1,000 acre. This is the plant pop-
ulation in seeds per acre.
Example 1:
If you have a 10-inch row spacing drill, according
to the table below, three rows must be counted.
Measure 17ft 5in and count the number of seeds
in three rows. If the number is, for example, 180,
multiply 180 by 1,000.
180 x 1,000 = 180,000 seeds per acre.
Example 2: Twin Row
If you have a Twin Row 30in- spacing drill, accord-
ing to the table below, both rows of the twin row
must be counted. Measure 87’1” and count the
number of seeds in the parallel row. If the number
is, for example, 170, multiply by 200.
170 X 200 = 34,000 seeds per acre
NOTE: Count Twin Row as one row.
7. If the planting population is significantly differ-
ent than desired, make the following checks:
• Double check the transmission and range
sprocket combinations. Refer to the seed pop-
ulation chart for the seed being planted.
• Check the air pressure in the gauge wheel
tires. Refer to “Tire Inflation Chart” on page
128.
• Refer to Troubleshooting on page 47.
Seed rate charts
Seed rate charts begin on page 96. The charts give
transmission sprocket combinations and drive
range sprocket combinations for each row spacing,
to achieve the population or pounds per acre de-
sired. The charts also give seed spacing for
singulated seed and maximum planting speed for
both singulated and volumetric seeds.
Each seed chart has a corresponding page show-
Planted row spacing
(inches)
Number of
rows to count
Length of row
to measure
for 1/1,000
acre
Length of
row to
measure for
1/200 acre
7 1/2in 4 17ft 5in
9 1/2in 3 18ft 4in
10in 3 17ft 5in
15in 2 17ft 5in 87ft 1in
19in 2 13ft 9in 68ft 9in
20in 1 26ft 2in 130ft 8in
Twin Row 30in or 30in 1** 17ft 5in 87ft 1in
Twin Row 36in or 36in 1** 14ft 6in 72ft 7in
Twin Row 38in or 38in 1** 13ft 9in 68ft 9in
Twin Row 40in or 40in 1** 13ft 1in 65ft 4in
15in Skip Row or 17 1/7 2 15ft 3in 76ft 3in
**Count Twin Row as one row.
NOTE: Use 1/200 acre for populations less than 100,000 seeds/acre. Use 1/1,000 acre for
populations above 100,000 seeds/acre.