Without a single tree in your yard, you can still be blessed
with massive numbers
of leaves.

Leaves’
journey

Fallen leaves can either travel miles or disintegrate
within a few feet of their tree.
The more surface area and the lighter a leaf’s weight, the
greater its chance of blowing
far away.

Leaves start their journey as life slowly ebbs away in
the fall. The leaf stem contains
strong, woody connections between leaf and trunk. Wind,
rain or animals can snap off these
connections. When they break, the leaves fall.

A leaf’s initial drop from the tree is when it has the
greatest chance of traveling the
farthest. On dry, windy days, leaves can swirl and sail
hundreds of yards.

Once on the ground, leaves can be pushed along by
ground-hugging breezes. Wet days and
heavy dews can ground many leaves. If they become wet or
matted-down, they will stay in
one spot and decay.

If they keep drying, though, and become lighter,
further wind-buoyed flight becomes
more likely.

There are reasons they travel
so well

Look at tree leaves on the ground. Most don’t lay flat.
The same internal structures
that held the living leaves upright on the tree now keep
them from laying perfectly flat
against the ground.

As they dry, many leaves twist and curl. The farther a
leaf sticks above its
surroundings, the greater is its chance for catching a
wave of wind.

Not only does the leaf blade help catch the wind, but
the stem, or petiole, can act as
one leg holding the leaf braced above the ground.

A leaf with several lobes and supporting veins can dry
into a multilegged stool holding
most of the leaf blade off the ground. The rolling and
curling of a leaf as it dries can
produce a “box kite” effect which the wind can catch.

Other leaves are small and light enough to remain
nearly flat but blow like snow flakes
across a yard. Most leaves cup or change shapes in some
way, which allows quicker drying
and better sailing at slower wind speeds.

After the
fall

After the leaves’ initial fall from the tree, the wind
tumbles and sweeps them along.
This is most noticeable on pavement and short-mowed
grass.

As leaves tumble, especially on hard surfaces, small
pieces are broken away. These
pieces can lay close to the ground and have less sail area
for the wind to catch.

The closer they get to the soil surface, the greater
the chance that leaves will absorb
more moisture. And at the physical surface of the ground
or pavement, the wind speed is
zero. The closer to the ground a leaf lies, the less
chance for wind to pick it up.

Leaves gather in drifts where the surface is rough
enough to catch them or the local
air turbulence produces small patches of less wind. The
size of the leaves and the height
of the drift show how much wind energy is present.

Bigger leaves gather at a tall curb-edge or along
fences. Small leaves drift around
corners and behind low landscape objects. Pine needles
stay close to home once they drop
because they’re hard for the wind to pick up and tumble.
Some curled or rolled oak leaves
can go on long journeys.

Leaves’ final
destination

Somewhere, the leaves finally resting spots at forest
edges, house foundations, porch
sides, stream beds. There they are matted down, crushed by
their associates and moistened
by winter rains.

Decay fungi and small animals chew and consume the
remaining parts. The result is the
recycling of the soil and air that built the leaf in the
first place.

Blowing leaves are just one step ahead of recycling.