Weeds L2

Question 1

example of person - place - time

Answer 1

person - dandelions in lawn
place - volunteer crops (or time)
time - kochia

Question 2

ecology weed definition

Answer 2

a plant that forms populations and enters habitats cultivated, disturbed, or occupied by man and can depress or replace resident populations which are cultivated or are of ecological and/or aesthetic value

Question 3

Agricultural weed defintion

Answer 3

any plant not intentionally sown or propagated by the grower that requires management to prevent it from interfering with crop or livestock production

Question 4

allelopathy

Answer 4

the positive and negative effects of plants on other organisms through chemical substances

Question 5

how do plants communitcate

Answer 5

above ground via volatiles
below ground via root exudates

Question 6

plant volatiles

Answer 6

chemicals that plants release into the air

Question 7

root exudates

Answer 7

chemicals exuded by roots of growing plants

Question 8

kin recognition

Answer 8

plants recognize if there is the same species next to them or if it is an alternate species

Question 9

how does kin recognition affect crops

Answer 9

crops have been bred to be less competitive with neighbors, which means that the presence of non-kin species can reduce yields

Question 10

Example of kin recognition

Answer 10

rice does not exude chemicals when next to rice, but produces more root excretes when next to a different species

Question 11

Potential strategy with kin recognition for improve weed management

Answer 11

make crops more competitive against weeds

Question 12

How are weeds classified?

Answer 12

habitat
structure and appearance/taxonomic relation
life cycle
origin

Question 13

Types of weed habitats

Answer 13

cropland, rangeland, forests, aquatic, and environmental weeds

Question 14

Example of weeds in forests

Answer 14

Scotch broom in British Columbia

Question 15

Example of weed in pastures

Answer 15

Nodding thistle - cattle don’t eat it

Question 16

Example of aquatic weed

Answer 16

Water Hyacinth - can completely clog waterways and make water inhabitable

Question 17

Suffix of most weeds

Answer 17

aceae

Question 18

How are weeds classified through structure and appearance?

Answer 18

Monocotyledons and dicotyledons

Question 19

monocotyledon

Answer 19

one cotyledon

Question 20

dicotyledons

Answer 20

2 cotyledons

Question 21

Types of monocotyledons

Answer 21

grasses, sedges, and rushes

Question 22

Types of dicotyledons

Answer 22

broadleaf plants

Question 23

grasses (poaceae)

Answer 23

annual of perennial
narrow, parallel-veined leaves
circular jointed stems that are hollow at internodes

Question 24

sedges (cyperaceae)

Answer 24

perennial grass-like plants that are common in wet, poorly drained soils
triangular, non-jointed stem that is solid

Question 25

rushes

Answer 25

annual or perennial plants that look similar to sedges grass-like tufted leaves circular, non-jointed stems that are hollow

Question 26

ferns

Answer 26

primitive perennial plants that do not produce flowers/seeds and reproduce by long rhizomes or spores consist of leaf/frond and a stalk

Question 27

Branken weed

Answer 27

causes sickness and death in livestock

Question 28

Types of life cycles

Answer 28

Summer annual Winter annual biennials perennials

Question 29

types of perennials

Answer 29

simple and creeping

Question 30

summer annuals

Answer 30

germinate in spring, mature, produce seeds, and die in the fall (1 growing season) most common type of weed in annually tilled fields

Question 31

examples of summer annual weeds

Answer 31

giant foxtail, smooth pigweed, common lambs quarters

Question 32

winter annual

Answer 32

germinate in late summer/fall, mature, produce seeds, and then die the following spring/summer problem in fall seeded crops, early spring grains, pastures, and no-till fields

Question 33

Winter annual weed examples

Answer 33

common chickweed, downy brome, annual bluegrass

Question 34

biennials

Answer 34

grow from seed anytime during the growing season, usually producing rosette first year, then flower, mature, and die second season Problem in no-till, pastures

Question 35

Examples of biennial weeds

Answer 35

wild carrot, bull/must thistle, poison hemlock

Question 36

perennials

Answer 36

live more than 2 years problem in no-till, pastures, roadsides, and row crops

Question 37

simple perennial

Answer 37

form a deep taproot and spread primarily by seed dispersal

Question 38

Example of simple perennial

Answer 38

dandelion, common pokeweed

Question 39

creeping perennial

Answer 39

either herbaceous or woody and can spread by both vegetative structures and seed

Question 40

Examples of creeping perennial (herbaceous and woody)

Answer 40

Herbaceous - canada thistle, common milkweed, common purslane Woody - poison ivy, bamboo, brambles

Question 41

Why do you have more problems with perennials with more tillage?

Answer 41

you spread the vegetative parts around

Question 42

Examples of parasitic weeds

Answer 42

mistletoe, broomrape, dodder

Question 43

How is mistletoe parasitic

Answer 43

birds eat berries and clean beak on trees to get rid of sticky seed. Grows on trunk and gets nutrients from host plant (can photosynthesize

Question 44

How is broomrape parasitic

Answer 44

Will germinate and connect to host plant with roots (cant photosynthesize)

Question 45

How is dodder parasitic

Answer 45

germinates in-ground and finds host plant to grab onto. will spread to other plants when host plant dies

Question 46

Types of weed origins

Answer 46

Native non-native/exotic/alien

Question 47

Native weeds

Answer 47

occur naturally in a place without human intervention

Question 48

non-native weeds

Answer 48

introduced to an area by people from other contents, states, ecosystems, or habitats

Question 49

Examples of weed species native to North America

Answer 49

Annual sunflower, common plantain, canada fleabane, bluebur, field horsetail, foxtail barley, giant ragweed

Question 50

Examples of alien weeds from Europe or eurasia

Answer 50

Green foxtail, wild oat, wild buckwheat, lambs quarters, canada thistle, dandelion

Question 51

invasive species

Answer 51

cases when exotic species aggressively displace native species and reduce land value

Question 52

common characteristics of invasive weeds

Answer 52

fast growth rapid reproduction high seed production and dispersal ability tolerance to lost of environmental conditions aggressive and prolific vegetative reproduction association with humans/human activities

Question 53

example of invasive weeds in Canada

Answer 53

Canada thistle (perennial) Garlic Mustard Slender foxtail