52 Nebraskaland • March 2026
MIXED BAG
It's not a moss. It's not a plant. And despite its sometimes
flaky, crusty appearance, it's definitely not mold growing on
a rock. Lichen is a partnership — a symbiotic relationship
between a fungus and either an algae or a cyanobacterium.
It's an impressive arrangement. The fungus provides
structure, holds moisture and protects its partner from harsh
environmental extremes, while the algae or cyanobacteria
can photosynthesize to create food from sunlight, which they
share with the fungus. When they team up, lichens can grow
on bare rock, rusty metal, sun-scorched bark, old gravestones
… you name it. That's why we find lichens in places where
most other living things would throw in the towel.
Lichen Diversity
Over 300 lichen species have been documented in
Nebraska, and there are likely more waiting to be discovered.
They grow slowly — some less than a millimeter per year —
but are incredibly tough. From growing on shady cottonwood
trunks along the Missouri River to sunbaked limestone
outcrops in the Sandhills, some species can withstand
freezing temperatures, drought and even radiation.
Some lichens form thin, tight crusts on stone that almost
looks like old paint, called crustose lichen. Others are looser
and leafier, curling up at the edges like old lettuce, called
foliose lichen. And then there are the bearded ones — those
shrubby, hair-like forms that dangle, resembling gray-green
beards on tree limbs, known as fruticose lichen.
Lichen as Environmental Indicators
Lichens have the ability to "speak" for the environment.
Because lichens don't have roots, they don't draw nutrients
from the soil like plants do. Instead, they absorb everything
— water, minerals and pollutants — straight from the
atmosphere. That makes them incredibly sensitive to air
quality, especially to substances like sulfur dioxide, ammonia
and nitrogen compounds from vehicle exhaust, power plants
or heavy fertilizer use.
In cities or areas near large-scale agriculture, it's not
uncommon to find only a few tough, pollution-tolerant lichen
species — ones that can hang on in conditions where others
simply can't survive. These lichens might be smaller, duller
in color or crustose types that hug tightly to stone and bark.
LICHEN — NATURE'S QUIET PARTNERSHIP
By Monica Macoubrie, Wildlife Education Specialist
Lichen on sandstone found at Toadstool Geologic Park. CHRIS MASADA
