Physical weed control

Question 1

Mechanical weed control

Answer 1

Main control method without herbicides

Effect by tearing out and spilling, cutting off

the best effect is achieved in young weeds

soil condition is decisive for the control success

there is a fine line between the success of combating and damaging to the crop

traditionally, the most imortant device is the plough (especially against root weeds)

for most devices a loose soil surface is a condition for a satisfactory effect

with careful preparation of seedbed many weeds can be controlled before the crop

correct setting of devices is often more important than choice of equipment

Question 2

Thermal weed control - flaming devices

Answer 2

Effect by rapid heating of the leaves (protein denaturation, dehydration), at least 70°C in the cell tissue.

easy to control: species with thin leaves and unprotected vegetation point (e.g. Chenopodium album, Stellaria media)

difficult to control: species with protected vegetation point or increased heat tolerance of the leaves (e.g. Senecio vulgaris, Polygonum spp., Capsella bursa- pastoris, Matricaria spp.)

almost not controllable: grasses (without Poa annua), many perennial dicots (e.g. Myosotis arvensis, Urtica dioica, Cirsium arvense)

Use: row crops, pre-sowing or pre-emergence, vegetable cultivation (onions), potatoes (cabbage killing), paved areas (herbicide use prohibited)

Question 3

Thermal weed control - Infrared process

Answer 3

working not with an open flame, but with radiators (not susceptible to uneven ground or wind, but only small speeds possible and high costs)

Question 4

Thermal weed control - Microwaves

Answer 4

Killing plant parts and seeds in the soil. This is energy-intensive, long treatment times necessary (15 - 30s)
Therefore only stationary use

Question 5

Negative aspect of flaming device

Answer 5

Microorganisms on top soil are killed

Damaging of crop

Question 6

Thermal weed control - electricity

Answer 6

irreversible damage to shoots and roots. Occasionally used on tracks and to control turnips adn thistles. Problematic user protection, no selectivity

Question 7

Thermal weed control - Steam

Answer 7

Hot water
Sterilization of soil in greenhouses, weed control n paved areas, first prototypes to control dock, yellow nutsedge and other neophytes on arable land

Question 8

Thermal weed control - Solarization

Answer 8

Heating soil (>65°C) under plastic film

Question 9

Soil cover

Answer 9

Living or dead mulch
Artificially applied mulch layer
Stretch film