Lecture 5 - Dispersal

Question 1

seed dispersal

Answer 1

moves seeds away from the parent plant, aiding colonization and adding to seedling survivorship

Question 2

seed shadow

Answer 2

defined as the density of propagules with increasing distance from parent

Question 3

what 2 elements of seed shadow

Answer 3

fecundity
dispersal kernel

Question 4

fucundity

Answer 4

rate of seed production

Question 5

Dispersal “kernel”

Answer 5

probability of seed dispersal around parent

Question 6

is unaided dispersal passive or active

Answer 6

passive autochory

Question 7

what characteristics of unaided dispersal do the seeds have

Answer 7

no obvious adaptations to ensure dispersal

Question 8

what is unaided dispersal is limited to a radius roughly ______ to the plants height

Answer 8

equal

Question 9

plants that disperse through unaided/passive dispersal

Answer 9

lambs quarters
redroot pigweed
stinkweed
ragged robin
cow cockle
cornflower

Question 10

explosive dehiscence

Answer 10

active autochory when seeds are physically projected away as pods split under tension

Question 11

example of weed with explosive dehiscence

Answer 11

storks bill and tongue leaf

Question 12

wind dispersal

Answer 12

anemonochory where seeds have special adaptation assist in dispersal

Question 13

examples of special seeds adaptations for wind dispersal

Answer 13

pappus, tuft of hair, or wing-like structures

Question 14

examples of weeds that disperse through wind using pappus

Answer 14

canada thistle, perennial sow thistle, narrow-leaved hawks beard, and canada fleabane

Question 15

examples of weeds that disperse through wind using other structures

Answer 15

yellow star of Bethlehem (spikes catch wind)
Larkspur (paper fringe catches wind)
yellow owl’s clover (honeycomb texture)
wild leak (light flat seeds)

Question 16

example of weeds that disperse through wind tumbleweeds

Answer 16

kochia and russian thistle

Question 17

water dispersal

Answer 17

hydrochory where weeds seeds float in bodies of water and are deposited on bank or water edge

Question 18

example of weeds that disperse through water

Answer 18

curled dock, barnyard grass, yellow cape cowslip, yellow floating heart

Question 19

who was George de Mestral and what weed inspired his invention

Answer 19

swiss engineer that was noticed burdock burs stuck to him and his dog. Inspired his quest to create velcro

Question 20

what is dispersal by animals outside called

Answer 20

ectozoochory

Question 21

what is dispersal by animals inside called

Answer 21

endozoochory

Question 22

ectozoochory

Answer 22

hooks and barbs catch in fur of animals and fall off later

Question 23

endozoochory

Answer 23

animals ingest seeds and discharge else where (can help break dormancy)

Question 24

elaiosome

Answer 24

protein rich base on seeds that attract insects that carry it off a short distance that also helps seed to avoid being eaten

Question 25

example of weeds dispersed by animals

Answer 25

common burdock, hounds tongue, blue bur, sand milkwort, leafy spurge, stickseed

Question 26

examples of weeds dispersed by birds

Answer 26

wild tomato, round-leaf mallow, field bindweed, killdeer, least sandpiper

Question 27

cultivation seed dispersal

Answer 27

moves seeds/rhizomes in seed bank in direction of travel

Question 28

combine seed dispersal

Answer 28

mechanical form of seed dispersal that disperses seeds further than any other mechanical vector

Question 29

what does the dispersal of seed through manure spreading depend on

Answer 29

whether or not the manure was composted depends on the animal (chickens destroy most seed) depends on feed (silage kills most seed)