LECTURE 32- Flora of New Zealand

what percent of NZ’s flora is endemic

82%

what is a lack of specialised flowers

• NZ flora is often dull in colour and radially symmetrical

• more general pollinator syndrome

• Pollination often occurs through wind or unspecialised insects

exception is bird pollinated plants (kakabeak, kowhai, pohutukawa)

what is heteroblasty

When a plant has different juvenile and adult forms

• Juvenile leaves will be smaller and ad different shape from adults

• E.g lancewood

what is divarication

Occurs in small leaved shrubs/juvenile trees with wide branch angles, interlacing branches, long internodes and weak apical dominance

• Looks like a fat fucking shrub

• Occurs in 10% of NZ’s native woody flora

what makes NZ’s flora unique

• lack of specialised flowers

• divarication

• heteroblasty

what factors contributed to lack of specialised flowers

• lack of pollinators with long tonues (butterflies, moths)

• pollinators needed easy access to nectar

what factors contributed to heteroblasty

• moa browsing. juvenile plants were unpalatable and adults could grow out of reach of moa

• harder to see juvenile leaves in low light of forest canopy

what factors contributed to divarication

• moa browsing

• too much effort for animals to reach leaves

• divarication offers protection from wind, salt spray and UV from high elevation

Conifer broadleaf forests

• Mix of gymnosperms and angiosperms

• Keeps leaves all year round

what are the 5 different strata (layers) of Conifer broadleaf forests

1. Emergent layer (30-40 m)

2. Canopy layer (20-25 m)

3. Understory (10-15 m)

4. Shrub layer (3-8 m)

5. Ground layer (0-1 m)

beech forests

• Dominated by 5 species of southern beech

• Previously known as nothofagus, now known as Fuscospora and Lophozonia

features of beech forests

• No emergent trees– beech trees are dominant

• Low species diversity and little undergrowth

• Vines and vascular epiphytes are absent

• Forest floor is covered in beech little

• Mainly in southern alps

• Small patches of forest throughout NZ

Alpine

• 30% of native vascular plants in NZ are alpine or sub-alpine

• Found above tree-line (1000-1500m above sea level)

Three major zones:

• Mountain shrubland

• Tussock herbfield

• Fellfield

alpine- mountain shrubland zone

• 100-300m above tree line

• Variety of species and unique leaf forms adapted to high wind and UV conditions

• thick, leathery, or tightly oppressed leaves

alpine- tussock herbfield zone

• Up to 500m above the tree line

• dominated by tussock grasses

• Herbs, woody daisies and flax also present

• Cushion bogs occur where drainage is poor

alpine- tussock fellfield zone

• >500m above tree line

• Low temps, heavy frost, strong wind, snow, and intense sun

• sparse and specialised vegetation

• Small prostate shrubs, small herbs and cushion plants present

• plants often grow in rocks/crevices for moisture and climate protection