Zanthoxylum americanum (Toothache Tree)

prickly ash

Image Citation: Paul Wray, Iowa State University,
Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 2: 444. Provided by Kentucky Native Plant Society. Scanned by Omnitek Inc.

Where Commonly Found:  Bluffs, uplands, rocky hillsides, open woods, and moist ravines, CT, MA, ME, NH, NY, RI, VT.

How to Identify:
(For unfamiliar words: Wikipedia Glossary of Botanical Terms).
Go Botany Key for Zanthoxylum americanum.
Missouri Botanical Garden’s description of Zanthoxylum americanum.  Click on more images.

Flower Color:  Yellowish Green, inconspicuous.
Flower Type: Dioecious. Axillary clusters (cymes).  
Male and Female flowers on separate trees, appearing on old wood.  Female flowers
Flower Time:  Spring
Leaf Arrangement:  
Leaf Type:  Compound, odd-pinnate, dark green leaves, up to 12″ long, with 5 – 11 leaflets each.  Stems and leaves have sharp, 1/2″ long prickles. Leaves, flowers, stems and fruit all emit a lemony scent.
Height:  8′- 20′
Seed Collection:  Female flowers produce clusters of rounded, reddish-brown, berry-like fruit, maturing in late summer with 1-2 shiny black seeds per fruit.

Attracts:  Bees, butterflies
Use:  Naturalizing into thickets.
Light:  Full Sun to Part Shade
Hardiness Zone:  3 – 7   USDA Zone Map
Soils:  Medium
Notes:  Zanthoxylum americanum (Toothache Tree), another common name is prickly ash, as it looks much like an ash tree with prickles, growing in thickets. Can be used as a naturalizing hedge.  Chewing on the bark or fruit produces a numbing effect, hence the common name.
Native to almost all of the continental US east of the Rockies, but RARE in NH and much of mid-Altantic and southeastern US: Biota of North America Program (BONAP) – North American Plant Atlas (NAPA).

Requested by Edgewood Nursery

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