Effect of narrow opener geometry on lateral surface soil movement and implications for no-till seeding. Aliakbar Solhjou

Effect of narrow opener geometry on

lateral surface soil movement and

implications for no-till seeding

Barbara Hardy Institute – Agricultural Machinery Research and Design, University of South Australia

2011

A. A. Solhjou, J. Fielke and J. Desbiolles

Institute for Sustainable Systems and Technologies

ISSTIntroduction

Tined no-till opener


ISSTExcessive soil disturbance


ISST

Excessive soil disturbance by tined no-till openers leads to increased:•Depth of soil cover on alternate furrows•Pre- emergent herbicide contamination above the seed zone•Weed seed germination•Soil moisture loss

Problems of excessive soil disturbance

Poor seed germination


ISSTMaterial and Methods

•A flat narrow point opener•Experimental design: randomized complete block design with n= 4 rep.•Treatments:Rake angles: 35°, 53°, 72° and 90°•Forward speed (v) : 8.2 km/h•Work depth (d): 120 mm

•Commercial bent leg opener•V= 8.2 km/h and d= 120 mm- n=2

Bent leg opener

Flat opener

1

2


ISSTRake angle


ISSTTracers location before tillage

15

Ver

tica

l int

erva

l (m

m)

0

90

75

450

0

30 -30

50

100

10 20 -20 -10

0

-2 -1 3

2

-3

30

60

1

Lateral interval (mm)

105

120

-6 -4 -5 5

4

6

120 90 60 -120 -90 -60


ISSTX-Y-Z digitising frame


ISSTLaser soil profile meter


ISSTMeasuring bottom soil profile with laser


ISSTTracer locations after tillage

90°

35°



Cross section of soil profile and tracer locations- n=4

α= 35°




α= 53°




α= 72°




α= 90°



Cross section of soil profile and tracer locations - n= 2 (commercial bent leg opener)

Bent leg


ISSTResults

1. Opener geometry strongly affects on patterns of surface soil movement.

2. Flat opener rake angles clear pre-emergent

herbicide above seed zone. However, these rake angles move pre-emergent herbicide onto the adjacent furrow.

3. Bent leg opener reduces soil movement on the

adjacent furrow (uniform seed germination).


ISSTResults

4. Bent leg opener reduces lateral surface soil movement (pre- emergent herbicide) into adjacent furrow compare to flat openers (crop safety).

Thank you


ISST


ISSTCommercial bent leg opener


ISSTEffect of rake angle on average lateral tracer movement



Cross section of soil profile and tracer locations - n= 2 (commercial bent leg opener)


ISSTEffect of rake angle on soil failure in the front of openers

35° 90°


ISSTTracer locations after tillage for

opener rake angle of 90° and commercial bent leg opener

α= 90°

Bent leg


ISSTEffect of rake angle on average lateral tracer movement

Education

Effect of narrow opener geometry on lateral surface soil movement and implications for no-till seeding. Aliakbar Solhjou