North America Non-native Plant

Paperbark-thorn

Botanical name: Vachellia sieberiana var. woodii

USDA symbol: VASIW

Native status: Not native but doesn't reproduce and persist in the wild

Synonyms: Acacia sieberiana DC. var. woodii (Burtt Davy) Keay & Brenan (ACSIW2)   

Paperbark-Thorn: A Mysterious Member of the Acacia Family Meet the paperbark-thorn (Vachellia sieberiana var. woodii), a plant that’s as enigmatic as its name suggests. This particular variety of the Vachellia genus has managed to keep many of its secrets well-hidden from the gardening world, making it something of a botanical ...

Paperbark-Thorn: A Mysterious Member of the Acacia Family

Meet the paperbark-thorn (Vachellia sieberiana var. woodii), a plant that’s as enigmatic as its name suggests. This particular variety of the Vachellia genus has managed to keep many of its secrets well-hidden from the gardening world, making it something of a botanical mystery that even plant enthusiasts might find intriguing.

What’s in a Name?

The paperbark-thorn goes by the scientific name Vachellia sieberiana var. woodii, though you might also see it listed under its former classification as Acacia sieberiana var. woodii. Like many plants that have undergone taxonomic shuffles, this species has had to adapt to new naming conventions as botanists have refined their understanding of plant relationships.

The Great Unknown: Geographic Origins

Here’s where things get interesting (and a bit frustrating for curious gardeners): the specific geographic distribution of this particular variety remains largely undocumented in readily available sources. While the broader Vachellia sieberiana species is known to have African origins, pinpointing exactly where var. woodii calls home requires more detective work than most gardening resources provide.

Growing the Mystery Plant

If you’re the type of gardener who enjoys a challenge and doesn’t mind working with limited information, paperbark-thorn might appeal to your adventurous spirit. However, there are some practical considerations to keep in mind:

The Challenge of Unknown Growing Conditions

Without clear documentation of this variety’s preferred growing conditions, USDA hardiness zones, or specific care requirements, growing Vachellia sieberiana var. woodii becomes an exercise in educated guesswork. This lack of readily available information means:

  • You’ll need to experiment with growing conditions
  • Success rates may vary significantly
  • Finding reliable sources for seeds or plants could be challenging
  • Specific care instructions aren’t well-established

What We Don’t Know (But Wish We Did)

The information gaps surrounding this plant are substantial. We don’t have clear data on its:

  • Mature size and growth rate
  • Invasive or noxious status
  • Wildlife and pollinator benefits
  • Wetland tolerance
  • Specific landscape applications
  • Propagation methods

Should You Plant Paperbark-Thorn?

Given the limited information available about Vachellia sieberiana var. woodii, most gardeners might want to consider better-documented alternatives. If you’re set on exploring unusual Vachellia species, you might have better luck with varieties that have more established growing guides and clearer native status information.

For gardeners interested in supporting local ecosystems, focusing on well-documented native plants in your area will typically provide more predictable results and clearer environmental benefits.

The Bottom Line

While the paperbark-thorn certainly has an intriguing name and may hold potential as a garden specimen, the lack of readily available information makes it a challenging choice for most gardeners. Sometimes the most honest advice is to acknowledge when we simply don’t know enough about a plant to recommend it confidently.

If you do decide to embark on the paperbark-thorn adventure, approach it as an experimental project rather than a sure bet, and be prepared to learn through trial and observation rather than following established guidelines.

Paperbark-thorn

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Fabales

Family

Fabaceae Lindl. - Pea family

Genus

Vachellia Wight & Arn. - acacia

Species

Vachellia sieberiana (DC.) Kyal. & Boatwr.

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA