Fraxinus- Ash

Question 1

Fraxinus

Answer 1

Ash

Question 2

Faxinus pennsylvanica var. subinteggerima

Answer 2

green ash

Question 3

Fraxinus nigra

Answer 3

Black ash

Question 4

Fraxinus mandshurica

Answer 4

Manchurian Ash

Question 5

Fraxinus americana

Answer 5

White ash

Question 6

Green ash characteristics

Answer 6

conical-upright oval grown
open (not dense)
single trunked
medium to high headed (good street tree)
mature- more cylindrical

Question 7

Green Ash Buds

Answer 7

opposite buds
terminal buds (yellow) are scaly, dark rusty brown*
Sparsely pubescent (hairy)
terminal buds often flattened and much larger than axillary buds (red) which tend to be rounded
very little space between terminal bud and axillary buds

Question 8

Green Ash- leaves

Answer 8

(good identifier)
Compound leaf- odd pinnate, 5-7 leaflets*
end leaflet (yellow) largest in size
serrate margins
petiolule leaflet attachment

Question 9

Petiole

Answer 9

is the stalk that holds the leaves/leaflets

Question 10

Petiolule (if present)

Answer 10

is the stalk that holds the leaflets (only on compound leaves)

Question 11

Rachis

Answer 11

the continuation of the petiole inside a compound leaf

Question 12

Sessile

Answer 12

means no petiolule- leaflet attached directly to petiole

Question 13

Green Ash Flower

Answer 13

dioecious; male flowers and female flowers on different trees
female flowers: more green, rugged and thick, can be prolific seed producers
flowers commonly appear before leaves

Question 14

Green ash fruit

Answer 14

Samara
wings are long, straight sided and thin; like a canoe paddle*

Question 15

Benefits of Dioecious trees in landscaping

Answer 15

Gravitate towards the males so there is less seeds dropping

Question 16

Green Ash- autumn colouration

Answer 16

golden-yellow
usually the last to get leaves in spring and the first to drop leaves in autumn (negative feature)

Question 17

Green Ash Bark

Answer 17

ashy, textured
non-descript

Question 18

Green ash cultivars

Answer 18

mostly tall, more narrow upright trees
Foothills Green Ash (male,seedless)
Patmore Green Ash
Prairie Spire Green Ash
Bergeson Green Ash

Question 19

Green Ash Pest

Answer 19

Most common: Ash flower gall mite (only affects male trees), ash plant bug, ash cone roller
Emerald ash borer (not yet in SK)

Question 20

Ash flower gall mite

Answer 20

mostly/only on male trees
mite attacks male flowers, causing them to form into a gall; retained for years
not overly harmful; cosmetic problem
“Tree broccoli” hang on for a long time

Question 21

Ash plant bug

Answer 21

nymphs live on underside of leaf
piercing action causes speckled look
behaves like an aphid

Question 22

Ash cone roller

Answer 22

rolls leaf
makes cocoons
not likely to kill tree
strange expression on tree; cosmetic

Question 23

Fraxinus nigra

Answer 23

black ash

Question 24

Black ash characteristics

Answer 24

Leaves look a little droopy, because of the length of the compound leaf
more columnar shape
prefer wetter sites
yellow/golden fall colour

Question 25

Black ash- cultivar/hybrid

Answer 25

cultivar most common ‘Fall Gold’
hybrids are more commonly planted- ‘Northern Treasure Ash’ (male), ‘Northern Gem’ (male)

Question 26

Black Ash- bud

Answer 26

axillary buds round
dark brown to black
often a small space between terminal bud and axillary buds

Question 27

Black Ash- Leaf

Answer 27

Rounded to broadly acute at base
tapered from well above the middle to a slender tip
7-11 leaflets (most commonly 9)
leaflets sessile
brown hairs at base of leaflet

Question 28

Fraxinus mandshurica

Answer 28

manchurian ash

Question 29

Manchurian ash- characteristics

Answer 29

ornamental
leaves longer than other ash; leaves droop more than black ash

Question 30

Manchurian Ash- leaf

Answer 30

largest number of leaflets (9-13) hence why they droop
leaflets sub-sessile (very short petiolule)
rusty hairs at base of leaflets
serrate leaf margins
rusty brown hairs along veins and at axils
rachis and petiole can be slightly winged (cannot roll between fingers)

Question 31

Manchurian ash- bud

Answer 31

axillary buds rounded dark brown to black
very little space between terminal bud and axillary buds
stems often two sided rather than rounded

Question 32

Manchurian Ash-bark

Answer 32

bark is golden colour

Question 33

Manchurian Ash- cultivar

Answer 33

Faxinus mandshurica “Mancana”: fairly common front yard tree
medium sized tree- showy
nice round shape

Question 34

Manchurian Ash- pest

Answer 34

cottony ash psyllid, “jumping tree lice”, not on green ash

Question 35

Cotton Ash psyllid

Answer 35

black and manchurian ash and hybrids are particularly affected.
devastating for trees
nymphs enter leaves like a leaf miner-difficult to spray or control
death of trees is very common