Seasonal growth

Question 0

What are budscales and what is their role?

Answer 0

Budscales are modified leaves

• prevent dessication meristem
• insulate against heat loss
• produce growth inhibitors

Question 1

What is a bud?

what are its parts?

Answer 1

An embryonic shoot

• apical meristem
• nodes
• internodes
• leaf primordia
• budscales

Question 2

What is meant by the term “flush”

Answer 2

cellular expansion of leaf primordia and division fro internode extension

Question 3

What are the 4 major growth types in woody plants?

Answer 3

• Short spurs
• epicormic shoots
• late season shoots
• determinate long shoots
• indeterminate long shoots

Question 4

List several points about short spurs

Answer 4

• preformed in lateral vegetative buds

- little internode extension

Question 5

List several points about epicormic growth

Answer 5

• brought on by sudden light exposure to bole
• grow upward
• more prominent in certain species
• arise from dormant buds on bole
• result in knot formation

Question 6

What does the term Lammas growth refer to?

Answer 6

Second flushing of apical buds in early summer/late fall due to warmth and moisture

Question 7

What is late season growth?

Answer 7

Once buds have set they can flush again in late summer/early fall due to heat and moisture

Question 8

What is prolepsis?

Answer 8

Prolepsis is late season growth that takes place on lateral buds

Question 9

What are two main growth patterns when it comes to the formation of new shoots?

Answer 9

Determinate long shoots
-growth is predetermined in preceding year

Indeterminate long shoots
-buds form only a portion of the next years growth

Question 10

Elaborate on determinate long shoots by listing some points
where does it happen?
when does it happen?
when does actual growth take place?
species examples?

Answer 10

• all parts of apical growth are determined in preceding year
• shoots are pre-formed in terminal vegetative buds
• growth happens early in the season
• temperate forests
• Fd, S, P, Yew
• symmetricaly formed trees

Question 11

Elaborate on indeterminate long shoots

Answer 11

• Growth that happens continuously in response to environmental cues and is largely undetermined until those environmental cues present themselves
• happens during current growth season
• Basal part is pre-formed
• Balance is indeterminate
• hw, L, Cw, Birch, Cottonwood
• slower than determinate growth

Question 12

What is phenology?

Answer 12

The study of temporal aspects of plant growth and development and their relation to climate.

goal is to program growth

Question 13

What can be done in phenology to control plant growth?

Answer 13

-photoperiodism
response to duration of light
attempting to inhibit phytochrome from signalling senescence
-moisture control
-temperature control

Question 14

what hormone is responsible for senescence?

Answer 14

Phytochrome

Question 15

outline some growth patterns for temperate zone trees

Answer 15

• short period of shoot elongation (3 months)
• lengthy dormancy period
• trees and seeds go into dormancy to survive winter

Question 16

what is dormancy?

Answer 16

a trees survival adaptation to survive the stresses of winter. Active growth and energy production are arrested until conditions become favourable again

Question 17

Outline the stages of dormancy

Answer 17

Quiescense

Dormancy

Quiescence

budbreak and growth

Question 18

what is happening hormonally during dormancy?

Answer 18

accumulation of growth inhibitors

Question 19

describe quiescense

Answer 19

quiescense is a pre and post dormancy state where environmental cues are resulting in the accumulation of growth inhibitors in the fall and growth producing hormones in the spring. Due to conflicting hormones the trees are not actively growing but are not yet fully dormant in the fall or “awakened” in the spring

Question 20

What are the two processes involved in cold hardiness

Answer 20

Tolerance
-movement of water in cell to extracellular spaces where freezing will not cause as much damage

Freezing avoidance

• accumulation of solutes in cytoplasm which act as a biological antifreeze
• not only does the antifreeze prevent freezing, this also allows the plant to reduce evaporation when it gets hot

Question 21

What are the two main environmental cues?

Answer 21

Photoperiod
-mild, short days
-requires cessation
Temperature
-cool, short days
-cool days, cold nights

Question 22

when is shoot growth most prominent?

Answer 22

Summer (end of march - end of July)

Question 23

when is root growth most prominent?

Answer 23

Spring and Fall

Question 24

when would you plant trees on the coast?

Answer 24

mid february to march

Question 25

when would you measure diameter for accurate data?

Answer 25

late fall / early spring

Question 26

What is the shoot to root ratio?

What is a good ratio for nursery trees?

Answer 26

shoot to root ratio is the ratio of shoot to root… duh

a good ratio would be widespread roots and short boles for nursery trees