Table 1.

Estimated burial depth of annual ryegrass seed, as a percent of total seed currently on the soil surface, by a range of tillage methods.

Purpose of Tillage	Tillage Method	Example	Percentage of Seed at Different Depths (cm)
			0	0 to 1	1 to 5	5 to 10	10 to 20
Shallow soil cultivation, for burial of seed and crop residue	Rotary harrow	Phoenix Harrow; evenly distributes soil to 5 cm.	15	50	35	0	0
	Autumn tickle	Kelly chain; distributes 90% of surface seeds to a depth of 1 to 5 cm.	10	30	60	0	0
Full disturbance to address soil constraints	Multiple	Soil inversion using a mouldboard plough	1	1	1	1	96
Crop seeding	Minimum tillage	Direct drill with full cut cultivation; tynes cultivate the soil to 5 cm and provide a disturbed seed bed.	10	50	39	1	0
	Zero tillage	Disc seeding: flat discs are used to create an opening in the soils (to 5 cm) which is followed by a tyne to deliver seed and fertiliser into the slot, often followed by a press wheel to close the slot.	95	2	3	0	0
	No-tillage	Knifepoint seeding; narrow tynes commonly referred to as knife points resulting in 5 to 20% cultivation of the soil surface to 5 cm. Knife points will throw a small amount of soil across the surface, effectively burying the surface seed.	10	80	10	0	0

Source: Weed Seed Wizard decision support tool [16].