Lecture 18

Question 1

clearing land for agriculture has resulted in what?

Answer 1

envr cost & not sustainable

Question 2

What do beneficial insects need to complete their life cycles? (6) Do crops have all of these things?

Answer 2

Overwintering sites

Alternative prey/hosts

Nectar or pollen resources

Moderated microclimates

Host plants

Aggregation sites – protection

NO

Question 3

why is it important to study landscape ecology of an insect?

Answer 3

determines what insects will be present in the crop

what’s around the crop will determine what insects will be present

Question 4

landscape

Answer 4

area that is spatially heterogeneous in at least one factor of interest

Question 5

patch

Answer 5

SA that differs from its surroundings in nature or appearance

Question 6

fragmentation

Answer 6

breaking up of habitat or cover type into smaller, disconnected parcels

Question 7

cover type

Answer 7

category within a classification scheme defined by the user that distinguishes among the different habitats ecosystems or vegetation types on landscape

Question 8

what enables the differentiation b/w the diff patches within the landscape?

Answer 8

cover type

Question 9

what restricts insects from moving among patches?

Answer 9

habitat fragmentation

Question 10

what are the 2 ways of measuring what’s in a landscape?

Answer 10

composition & configuration

Question 11

composition

Answer 11

proportion of diff habitats that occur within a landscape

habitat richness & diversity

Question 12

configuration

Answer 12

have the same composition but can be connected or fragmented

habitat connectivity & fragmentation

Question 13

complex landscapes have significantly: (7)

Answer 13

o 1 – Higher % of deciduous forests
o 2 – Lower % area cover by crops
o 3 – Smaller fields
o 4 – Wider field borders
o 5 – Taller vegetation in the border
o 6 – Richness of tree species in the border
o 7 – Higher % of trees/shrubs in the border

Question 14

describe the diet of true armyworms

Answer 14

generalist, attack several crops

Question 15

how are true armyworms controlled?

Answer 15

by natural enemies

Question 16

Meterous communis

Answer 16

generalist endoparasitoid mainly on Noctuidae

solitary

alternative hosts

Question 17

Glyptapanteles militaris

Answer 17

generalist endoparasitoid mainly on Noctuidae

gregarious

alternative hosts

Question 18

what is the main diff b/w Glyptapanteles militaris & Meterous communis?

Answer 18

Glyptapanteles militaris mainly feeds on grasses & forbs

Question 19

higher % of parasitism in ______ than in ______

Answer 19

comlex

simple

Question 20

how are melon aphids controlled?

Answer 20

by many natural enemies

Question 21

what habitats benefit the natural enemies of melon aphids? (6)

Answer 21

% area of:

	Alfalfa
o	Cucurbits
o	Other crops 
o	Native vegetation 
o	Riparian vegetation 
o	Grassland

Question 22

Do we benefit from predators arriving early to the crops?

Answer 22

YES! Delaying the arrival of predators impacted the aphid population growth

Question 23

what is the most important vegetation in determining the survival rates of aphids?

Answer 23

alfalfa

decres survival = incres in alfalfa

Question 24

how do you enhance natural enemy impacts?

Answer 24

incers flowering species

Select diff species that may be possible to place at the sites of the fields or close to it that have these flowering plants so at diff times of the season they provide the nectar & pollen to provide them with enough E to move into crops

Question 25

how do complex landscapes affect beneficial insects?

Answer 25

by providing resources from non-crop habitats

Question 26

natural enemies _____ their abundance in complex habitats

Answer 26

increase

Question 27

pes suppression in complex landscapes is _____

Answer 27

higher