tree growth

Importance of height grown & shoot elongation
1) maintain favorable competitive status
2) build leaf area
3) volume production (mass)
What are the 4 determinants of annual shoot elongation?
Number of stem units vs. internode length
1. species
2. growth rate
3. branch order
4. shoot position
what are the 6 controls on height growth?
1. age
2. genetics (genotype, species)
3. site quality
4. environmental conditions
5. silviculture
6. weather
what are the 5 environmental conditions on height growth?
1. nutrients
2. moisture
3. light
4. stand density
5. extreme conditions
What are the two basic crown growth forms?
1. excurrent
2. deliquescent (decurrent)
What are the factors affecting crown growth form?
1. species
2. age
3. stand density, stand form, site quality
How can a excurrent growth form be described?
as a single stem with branches coming off of the stem
How can a deliquescent growth form be described?
multiple stems with branches coming off of all of them
what are the 4 factors affecting crown form/crown development?
1. branch angle
2. environmental stimuli
3. epicormic branching
4. damage (ice storm, insect/disease, & animal)
when referring to crown development what does plagiotropism mean?
horizontal growth
when referring to crown development what does orthotropism mean?
vertical growth
when referring to crown development what does geotropism mean?
root growth (downward growth)
when referring to crown development what does phototropism mean?
growing towards light
how does leaf area develop over time?
1. rapid increase in in juvenile stage
2. relatively constant average leaf area per tree through most of the mature stage
3. continued slow increase in leaf area through senescent stage
how is the stem form relative to the crown?
1. total stem growth is dependent on how much leaf area is in the crown
2. the width of the annual growth ring at any point on the stem varies with stem position relative to crown
What are the 3 tree growth stages?
1. youth (juvenile, formative, lag phase)
2. maturity (mature, grand, exponential phase)
3. senescence (mature deceleration phase)
In between what two stages does the peak growth rate occur?
youth (juvenile) & maturity
define free growth
1. initiation and elongation of new stem units
2. it is characteristic of all first year seedlings with no bud
3. it is characteristic of most genera in family in cupressaceae
4. accounts for fox tailing in some pines
define fixed growth
1. shoot initiation and growth occurs overs 2 growing seasons
2. shoot length restricted to the number of stem units formed in the bud of the previous year.
define fixed + free growth
1.elongation of spring shoot, which is the fixed growth, if followed by one or more flushes of summer shoots, which is known as free growth.
2. each new flush is capable of producing a whorl of lateral branches
3. the number of summer shoots varies with environmental conditions, relative shoot, vigor, & position of shoot on the tree.