North America Non-native Plant

Thalictrum Squarrosum

Botanical name: Thalictrum squarrosum

USDA symbol: THSQ

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

Thalictrum squarrosum: A Botanical Mystery Worth Investigating If you’ve stumbled upon the name Thalictrum squarrosum in your gardening research, you might be scratching your head wondering why information about this plant seems so elusive. Well, you’re not alone, and there’s a good reason for the confusion! The Mystery of the ...

Thalictrum squarrosum: A Botanical Mystery Worth Investigating

If you’ve stumbled upon the name Thalictrum squarrosum in your gardening research, you might be scratching your head wondering why information about this plant seems so elusive. Well, you’re not alone, and there’s a good reason for the confusion!

The Mystery of the Missing Meadow-Rue

Here’s the thing about Thalictrum squarrosum: it appears to be either an extremely rare, obsolete, or potentially invalid botanical name. While the genus Thalictrum (commonly known as meadow-rue) is well-established and includes many beautiful native species, squarrosum doesn’t show up in current taxonomic databases or horticultural references.

This could mean several things:

  • It might be an old name that’s been reclassified under a different species
  • It could be a regional or colloquial name that wasn’t formally recognized
  • There might be a spelling variation or error in the original source
  • It could refer to a very rare or recently discovered species not yet widely documented

What We Do Know About Meadow-Rues

While we can’t provide specific information about Thalictrum squarrosum, we can tell you that the Thalictrum genus includes some absolutely delightful native plants that deserve consideration for your garden. These graceful perennials are known for their delicate, cloud-like flowers and attractive foliage that adds texture and movement to garden beds.

Most meadow-rues are excellent choices for native gardens, offering benefits to pollinators and fitting beautifully into woodland or naturalized landscapes. They typically prefer partial shade and moist, well-draining soil.

Our Recommendation

If you’re interested in adding a meadow-rue to your garden, we’d suggest looking into well-documented native species in the Thalictrum genus that are appropriate for your region. Some popular options include Thalictrum dioicum (early meadow-rue), Thalictrum dasycarpum (purple meadow-rue), or Thalictrum thalictroides (rue-anemone, though technically now classified as Anemonella thalictroides).

Before purchasing any plant labeled as Thalictrum squarrosum, we’d recommend verifying the plant’s true identity with the supplier and ensuring you’re getting a species that’s well-suited to your growing conditions and native to your area.

The Bottom Line

Sometimes in the world of gardening, we encounter botanical names that lead us down rabbit holes of research. While Thalictrum squarrosum remains a mystery, this gives us a perfect opportunity to explore the wonderful world of meadow-rues and choose from the many documented species that will bring beauty and ecological value to our gardens.

If you have any information about Thalictrum squarrosum or have encountered this name in your gardening journey, we’d love to hear from you! The botanical world is full of surprises, and sometimes these mysteries lead to fascinating discoveries.

Thalictrum Squarrosum

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Magnoliidae

Order

Ranunculales

Family

Ranunculaceae Juss. - Buttercup family

Genus

Thalictrum L. - meadow-rue

Species

Thalictrum squarrosum Stephan ex Willd.

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