North America Native Plant

Dictyonema Moorei

Botanical name: Dictyonema moorei

USDA symbol: DIMO10

Habit: lichen

Native status: Native to North America  

Dictyonema moorei: The Mysterious Lichen You Might Already Have in Your Garden Have you ever noticed grayish, crusty patches growing on the bark of trees in your yard and wondered what they might be? You could be looking at Dictyonema moorei, a fascinating lichen that’s quietly contributing to your garden’s ...

Dictyonema moorei: The Mysterious Lichen You Might Already Have in Your Garden

Have you ever noticed grayish, crusty patches growing on the bark of trees in your yard and wondered what they might be? You could be looking at Dictyonema moorei, a fascinating lichen that’s quietly contributing to your garden’s ecosystem in ways you might never have imagined.

What Exactly Is Dictyonema moorei?

Before we dive deeper, let’s clear up a common misconception. Dictyonema moorei isn’t actually a plant in the traditional sense – it’s a lichen! Lichens are remarkable organisms that represent a partnership between fungi and algae or cyanobacteria. Think of them as nature’s ultimate roommates, working together to create something neither could achieve alone.

This particular lichen is native to North America and can be found naturally occurring in the southeastern United States. Unlike the plants you might typically cultivate in your garden, Dictyonema moorei can’t be planted, watered, or fertilized in any conventional way.

How to Spot Dictyonema moorei in Your Garden

Identifying this lichen is like becoming a nature detective. Here’s what to look for:

  • Grayish, crusty patches that appear almost painted onto tree bark or rock surfaces
  • A flat, spreading growth pattern that follows the contours of its host surface
  • Texture that might remind you of dried paint or a thin layer of concrete
  • Presence on mature trees, particularly on the north-facing or shaded sides of trunks

Is This Lichen Friend or Foe?

Here’s some great news for worried gardeners: Dictyonema moorei is absolutely beneficial to have around! This lichen is actually a sign that your garden ecosystem is healthy and thriving.

Lichens like Dictyonema moorei serve as natural air quality indicators. Their presence suggests that your local air is relatively clean, as lichens are quite sensitive to pollution. They’re also incredibly important for biodiversity, providing tiny habitats for various microorganisms and small invertebrates.

The Hands-Off Approach to Growing Lichens

If you’re hoping to encourage more Dictyonema moorei in your garden, the best approach is actually the most hands-off one possible. Here’s what you can do:

  • Maintain mature trees and avoid unnecessary bark scraping or power washing
  • Minimize the use of chemicals and pesticides in your garden
  • Allow natural processes to occur without interference
  • Create diverse microhabitats by maintaining both sunny and shaded areas

A Word of Caution

While Dictyonema moorei is harmless to trees and beneficial to your garden ecosystem, it’s important not to try to help it spread by scraping it off one surface and attempting to transplant it elsewhere. Lichens have very specific growing requirements and are best left to establish naturally.

Embracing the Wild Side of Your Garden

Finding Dictyonema moorei in your garden is like discovering a hidden treasure. It’s a reminder that even in our carefully cultivated spaces, wild nature finds a way to establish itself and contribute to the complex web of life that makes gardens truly special.

Rather than viewing these crusty gray patches as something to remove, consider them badges of honor – proof that your garden is supporting the kind of biodiversity that makes ecosystems resilient and beautiful in their own unique way.

Dictyonema Moorei

Classification

Group

Lichen

Kingdom

Fungi - Fungi

Subkingdom
Superdivision
Division

Basidiomycota - Basidiosporic fungi

Subdivision
Class

Basidiomycetes

Subclass

Holobasidiomycetidae

Order

Stereales

Family

Corticiaceae Herter

Genus

Dictyonema C. Agardh - dictyonema lichen

Species

Dictyonema moorei (Nyl.) Henssen

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