North America Native Plant

Woollyleaf Manzanita

Botanical name: Arctostaphylos tomentosa insulicola

USDA symbol: ARTOI

Life cycle: perennial

Habit: shrub

Native status: Native to the lower 48 states  

Woollyleaf Manzanita: A Rare California Native Worth Protecting If you’re a California native plant enthusiast, you might have stumbled across the name Arctostaphylos tomentosa insulicola, commonly known as woollyleaf manzanita. But before you rush to add this shrub to your garden wish list, there’s something important you need to know ...

Rare plant alert!

Region: Conservation status by state

Status: S4T3: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals. ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘

Woollyleaf Manzanita: A Rare California Native Worth Protecting

If you’re a California native plant enthusiast, you might have stumbled across the name Arctostaphylos tomentosa insulicola, commonly known as woollyleaf manzanita. But before you rush to add this shrub to your garden wish list, there’s something important you need to know about this particular plant.

What Makes This Manzanita Special?

Woollyleaf manzanita is a perennial shrub that belongs to California’s beloved manzanita family. Like its relatives, it’s a multi-stemmed woody plant that typically stays under 13-16 feet tall, making it a manageable size for most landscapes. These shrubs usually develop several stems from ground level, creating that classic manzanita silhouette that California gardeners adore.

Where Does It Call Home?

This native beauty is exclusively found in California, making it a true Golden State endemic. As a plant native to the lower 48 states, it has deep roots in the local ecosystem and has evolved alongside California’s unique climate and wildlife.

The Rarity Factor: Why This Matters

Here’s where things get serious. Arctostaphylos tomentosa insulicola carries a Global Conservation Status of S4T3, which indicates conservation concern. This means the plant faces some level of threat in the wild, and its populations may be limited or declining.

What this means for gardeners: While we absolutely support growing native California plants, this particular species requires extra consideration. If you’re determined to grow this specific variety of woollyleaf manzanita, please ensure you source it responsibly from reputable native plant nurseries that propagate from legally and ethically collected seeds or cuttings.

Garden Design Considerations

As a California native shrub, woollyleaf manzanita would naturally fit into:

  • Mediterranean-style gardens
  • Drought-tolerant landscapes
  • Native plant gardens
  • Wildlife habitat gardens

The multi-stemmed growth habit makes it excellent for creating natural-looking boundaries or filling in middle layers of a layered native landscape design.

Growing Conditions and Care

While specific growing information for this exact variety is limited, manzanitas generally prefer:

  • Well-draining soils
  • Full sun to partial shade
  • Minimal summer water once established
  • Good air circulation

Given California’s climate, this plant is likely adapted to dry summers and mild, wet winters – the classic Mediterranean pattern.

A Responsible Approach

Before seeking out this particular variety, consider exploring other manzanita species that are more readily available and less conservation-sensitive. California has dozens of manzanita species and varieties, many of which offer similar aesthetic appeal without the conservation concerns.

If you do choose to grow Arctostaphylos tomentosa insulicola, please:

  • Source only from reputable native plant nurseries
  • Never collect from the wild
  • Consider participating in seed collection programs if available
  • Share information about its conservation status with other gardeners

The Bottom Line

Woollyleaf manzanita represents the beauty and uniqueness of California’s native flora, but its conservation status reminds us that some plants need our protection more than our cultivation. While it could make a lovely addition to the right garden, responsible sourcing and consideration of more common alternatives might be the better path for most gardeners.

Remember, every native plant we grow helps support local ecosystems – but sometimes the best way to support a rare plant is to help protect its wild populations while choosing more common natives for our own gardens.

Woollyleaf Manzanita

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Dilleniidae

Order

Ericales

Family

Ericaceae Juss. - Heath family

Genus

Arctostaphylos Adans. - manzanita

Species

Arctostaphylos tomentosa (Pursh) Lindl. - woollyleaf manzanita

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