Weed Mgmt And Control, Part2

Front 1

How can soil fertility be a cultural management technique?

Back 1

Species able to utilize soil nutrients will have a competitive advantage, so band fertilizer instead of broadcast

Front 2

What is the pH range for most crops?

Back 2

6-6.5

Front 3

Name the weeds and their indicators.

Back 3

Low pH indicator-- red sorrel
Compaction-- goosegrass
Poor drainage-- dollarweed
Low N-- legumes
High pH-- plaintains

Front 4

What are natural reasons for voids?

Back 4

environmental stress (flooding, lightning, hurricanes), animals, diseases, insects, nematodes

Front 5

What are management reasons for voids?

Back 5

improper mowing, improper fertility, improper irrigation, lack of core cultivation, lack of thatch mgmt, lack of traffic control

Front 6

What are some weed management strategies for summer grasses (crabgrass, goosegrass)?

Back 6

Avoid establishment at time of grass germination
Avoid core cultivation at time of germ
Lower mowing height when grass is setting seed or collect clippings
Relieve soil compaction
Apply pre-emergence herbicide

Front 7

What are some weed management strategies for winter grasses (annual bluegrass)?

Back 7

Species most competitive with close mowing, high water, high N
Correct drainage, raise mowing height
Avoid cultivation at germination
Collect clippings

Front 8

What are some weed management strategies for perennial weeds in turf?

Back 8

Maintain dense turf through proper fertility, proper mowing, insect and disease control
Spot treat or physically remove isolated patches
Apply postemergence herbicides

Front 9

What is the difference between ecological and applied biological control?

Back 9

In ecological, you put it out there and they are on their own. In applied, you need a continual introduction of biocontrol agents to suppress weed population

Front 10

What are some examples of biocontrol?

Back 10

prickly pear cactus--moth borer
water lettuce and water hyacinth
grass carp
N. jointvetch
melaleuca- psyllid, weevil
alligatorweed- flea beetle

Front 11

What is a parasite?

Back 11

a species which lives in or on a larger host, feeding upon it and frequently destroying it (mistletoe, leeches)

Front 12

What is a parasitoid?

Back 12

an insect which is only parasitic in its immature stages and will destroy host in the process of development

Front 13

What is a predator?

Back 13

an animal which feeds upon other organisms (grass carp, sheep, cattle)

Front 14

What is a pathogen?

Back 14

a microorganism that causes disease in a target organism (mycoherbicides)

Front 15

What are 5 characteristics of a good biological system?

Back 15

host specific (selective) + non-important alternative host
effective
favorable host plant synchonization
prolific and thrive in widespread areas that the weed occupies
good colonizers

Front 16

Where does biocontrol fit?

Back 16

perennial crops, low input cropping systems
rapid control not necessary
complete control not necessary
monoculture of one target weed
natural ecosystem ideal situation

Front 17

Why is there a time lag for biocontrol?

Back 17

no effect early on
never a true monoculture
preference of agent

Front 18

What are some methods of mechanical weed management?

Back 18

hand pull, tillage, cultivation, mowing, large equipment, mulches, flooding, fire, heat

Front 19

What are (dis)advantages to hand pulling?

Back 19

Adv. preferred in underdeveloped countries, selective
Disadv. money (labor), time

Front 20

What is mechanical weed management?

Back 20

anything that employs a physical force

Front 21

What are advantages of tillage?

Back 21

breaks weeds apart/pulls
dessicates
exhausts food reserves
reduces seed bank

Front 22

What are disadvantages of tillage?

Back 22

erosion
buries weed seed
raises weed seed
damages roots
compaction
serveral operations must be performed

Front 23

What 3 things can you do for conservation tillage (no-till)?

Back 23

1. spray for weeds
2. plant directly into residue
3. control weeds with herbicides

Front 24

What weeds do no-till and conventional tillage have come up?

Back 24

no-till has perennials while conventional has small-seeded annuals

Front 25

What is the primary tillage equipment?

Back 25

moldboard plow
disk harrow
spring tooth harrow
planter

Front 26

What is the secondary tillage equipment and what does it do?

Back 26

disk harrow and field cultivator
It levels, firms, breaks up clods and leave a suitable seedbed

Front 27

What does mowing do to annuals and perennials?

Back 27

Annuals- kills plant, prevents seed formation
Perennial- deplete reserves--> allow grasses to become competitive

Front 28

What types of mowers are there?

Back 28

reel, rotary, flail, sicklebar

Front 29

What types of large equipment are there?

Back 29

bulldozer, chaining, roller chopping, web plow

Front 30

What do you use large equipment for and what are the disadvantages?

Back 30

brush and woody plant control, generally expensive and long-term

Front 31

What is the purpose of mulches?

Back 31

excludes light and prevent growth

Front 32

What are the disadvantages of mulches?

Back 32

limited to small acreage, limited to transplants or specialized seeding, poor control of nutsedge, need drip irrigation, disposal of plastic is problem, not permanent

Front 33

What types of mulches are there?

Back 33

organic (straw, wood chips)
inorganic (rock, gravel)
synthetic (black plastic)

Front 34

What does flooding do to weeds?

Back 34

shift in species

Front 35

What is the opposite of flooding and what is it used for?

Back 35

drawdown for aquatic weed control

Front 36

What is fire used for and what are the disadvantages?

Back 36

used on certain crops with a tough bark
disadv. hazard, cumbersome

Front 37

What are 2 other mechanical management techniques?

Back 37

heat, microwave