Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

PLSC 260 > Weeds L5 > Flashcards

Weeds L5 Flashcards

1
Q

4 approaches to weed management

A

Prevention, eradication, control, management

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Weed prevention

A

preventing the introduction, establishment, and spread of weed species in areas not currently infested

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Weed eradication

A

the complete elimination of all live weeds, weed parts, and weed seed from an area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Weed control

A

Reducing weeds to minimize weed competition and provide the greatest economic return from the crop

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Weed management

A

the combination of the techniques of prevention, eradication, and control to manage weeds in a crop, cropping system, or environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Forms of integrated weed management

A

Mechanical (physical) control
Cultural control
Biological control
Chemical control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Every weed management option is a ____________ on the weed population

A

selection pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the most practical approach to weed management?

A

weed prevention

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Weed prevention practices

A

avoid using crop seed infested with weed seed
clean farm machinery thoroughly before moving to a different field
monitor field for new weed problems and remove them before they get out of hand
compost manure prior to field application

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Common methods of mechanical weed control

A

hand-pulling
hoeing
mowing
tillage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Hand-pulling

A

physical removal of weeds by hand
effective against annuals, biennials, and upper portions of perennials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hoeing

A

Cheap method of removing weeds
effective against annuals and biennials, but less effective on perennials because it only destroys top growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Mowing

A

Machine operated practice that should be done before flowers open to prevent seed production
more effective on tall weeds than short ones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What does mowing success on weed management depend on

A

repeated mowing to deplete weed’s food reserve
mowing should be done between full leaf development and flowering because food reserves are the lowest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

tillage

A

non-chemical weed control that removes weeds from soil and buries them
works best under dry, hot conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does tillage influence weed composition?

A

increases # of perennial and annual species that have seeds with long life spans
type and frequency of tillage influences composition and density of weed species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Pre-seeding tillage

A

prepares seed bed so planting occurs at uniform depth and controls weeds prior to seeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

negative effects of pre-seeding tillage

A

lose moisture and cause erosion, inhibiting successful crop establishment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

post-harvest tillage

A

shallow tillage that avoids burying weed seed that is effective in controlling winter annuals, biennials, and some perennials

20
Q

Smmerfallow tillage

A

Shallow tillage to avoid bringing weed seed to surface that is partially effective in controlling perennials and dormant seeds of annuals

21
Q

post seeding tillage

A

done by harrowing, rotary hoeing, or using a rod-weeder to kill weeds that emerge before the crop (important to ensure that crop has not sprouted in the tillage zone)

22
Q

At what conditions will you receive the best result when using post-seeding tillage

A

a warm sunny day when the soil is dry

23
Q

post-emergence tillage

A

done on weeds that emerge shortly after crop
tillage cannot be deep and a certain amount of crop damage is likely to occur

24
Q

Row-crop tillage

A

Crops are planted in wide rows to allow for inter-row tillage (can cause more weed germination so multiple passes are necessary)

25
Q

Flooding

A

roots and shoots of weeds are covered by water for long periods of time to deprive weed of air

26
Q

Mulching (smothering)

A

use of non-living material/mulch to exclude light from weeds

27
Q

allelopathic mulches

A

crop species that release allelopathic chemicals that can be used to retard weed growth

28
Q

Example of allelopathic mulch

A

crop residues of fall rye incorporated into soil to inhibit weed species like wild oat
Sweet clover as green manure

29
Q

soil solarization

A

Transparent and opaque polyethylene sheets are placed on moist soil to produce high soil temps that kills weeds (seedling/seed) and pathogens

30
Q

Flaming (burning)

A

use of flames generating a high enough temp over a sustained period of time to kill weeds and seed within top soil layer

31
Q

Cultural weed control

A

crop management practices that optimize the growth of crop plants and enable the crop to compete more effectively with weeds

32
Q

Crop rotation effect on weed control

A

can have greater weed control effect than tillage (especially when using weed suppressing cover crops)

33
Q

Seeding date effect on weed control

A

Seeding time is the main factor that determines weed composition as it is essential that the crops develop a good uniform stand in order to compete

34
Q

Benefits of delayed seeding

A

offers tillage options before seeding and after harvest to control early germinating weeds

35
Q

Types of weeds that can be controlled by late seeding

A

controls wild oat, wild buckwheat, and certain mustard species

36
Q

how does varying seeding dates limit weeds ability to adapt

A

doesn’t allow them to germinate earlier or later to avoid control methods

37
Q

seeding rate effect on weeds

A

Increasing seed rates 20-50% above normal can increase competitiveness of some species (can only be increased to a certain limit)

38
Q

What does increased seed rate do to the crop

A

Earlier crop maturity (few days)
Reduced tillering and shorter
Higher yield (to a certain limit)
increase competition, disease, and lodging losses

39
Q

When should increased seed rates be used

A

when either post-seeding or post-emergence tillage is planned to compensate for any crop damage

40
Q

Seeding depth effect on weeds

A

Seeds are placed at optimum depth to allow quick and even emergence to give crops better competitive ability

41
Q

What does optimum seeding depth depend on?

A

crop species
seed size
soil type and moisture conditions

42
Q

General rule for seeding depth

A

planted around 2-3 times as deep as the height of the seed

43
Q

Row spacing effect on weeds

A

narrow spacing means less open space for weeds to grow and offers better competition advantages for less competitive crops

44
Q

Plant nutrition effect on weeds

A

insuring soil nutrients is balanced to keep crop healthy and give it a better advantage

45
Q
A

PLSC 260 (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions