Rhamnaceae (buckthorn family)

Question 1

What family is Rhamnaceae?

Answer 1

Buckthorn family

Question 2

Key features:

Answer 2

• Leaves simple w alternately pinnate veination
• cup-shaped flowers, small, greenish/white, in axillary clusters
• flower parts in 5

Question 3

How did common buckthorn (Rhamnus cathartica) get it’s common name?

Answer 3

Derives from the thorn that often develops between two terminal buds at branch ends

Question 4

Where would you most typically find common buckthorn?

Answer 4

Upland areas, oak woodlands

Question 5

Where would you most typically find glossy buckthorn (Frangula alnus)?

Answer 5

Wetland areas

Question 6

What’s the difference between the terminal bud of the two buckthorns?

Answer 6

Glossy buckthorn’s is “naked” and pubescent. Common buckthorn’s is sharp and between two horns.

Question 7

What is it about the fruiting characteristics of glossy buckthorn that might lead to it’s success as an invader?

Answer 7

Ripens continuously through summer with seeds dispersed by birds.

Question 8

What are the two members of the rhamnaceae family that are native to MN?

Answer 8

Ceanothus americanus (New Jersey Tea), C. herbaceus (Narrow-leaved New Jersey Tea)

Question 9

Would they make good landscape plants? Where?

Answer 9

Yes, in tropical to temperate regions

Question 10

Why is common buckthorn such a successful invasive plant?

Answer 10

• grows in full sun to full shade and
• dry to moist
• most any soil

Question 11

Why is glossy buckthorn such a successful invasive plant?

Answer 11

• seeds spread by birds and gives diahrrea to all who ingest them