Mechanical management of weeds - Ecological Management of Agricultural Weeds - page 147

Table 4.3. Number of operations, interval between operations, and time required to eradicate some perennial weeds by fallow cultivation
directed primarily toward exhaustion of perennating organs

Minimum operations a Minimum time to eradicate

Interval c Eradication Interval c Eradication

Species Experiments b Operations (days) time (years) Operations (days) time (years) Reference

Convolvulus arvensis 8 18 20 2.2 26 12 1.8 Timmons & Bruns (1951)

Centaurea repens 2 22 25 2.5 24 18 2.0 Timmons & Bruns (1951)

Lepidium draba 2 14 28 1.8 18 18 1.6 Timmons & Bruns (1951)

Apocynum cannabinum 1 17 28 3 17 28 3 Timmons & Bruns (1951)

Sorghum halepense 3 7 28 1 7 28 1 Timmons & Bruns (1951)

Cyperus rotundus 1 16 21 2 Smith & Mayton (1938)

Cirsium arvense 1 10 18 2 Hodgson (1970)

Agropyron repens 4 4 25 0.5 Fail (1956)

Agrostis spp. 3 3 19 0.2 Fail (1956)

Agropyron repens d 7 4 25 1 Håkansson (1969 b )

Notes:
a Astrategy that minimizes the number ofcultivations often requires longer to achieve complete eradication.
b Sample size for means shown in the other columns.
c Interval between cultivations during the first year.Usually the interval was increased in subsequent years as the weeds weakened.
d Plants buried to controlled depths.