Soft Landings

0e371bf75b4a968b63e6fbb73d0dff4e5c2725ce (1)

Photo from pollinatorsnativeplants.com/softlandings

That patch of grass under your tree could be transformed into a habitat that supports the life cycle of caterpillars and many beneficial insects.

Photo from pollinatorsnativeplants.com/softlandings

2_Neal_Dake_Fort_wayne_46835_141342_i8quyo

What are soft landings

Soft landings are diverse native plantings under native trees, especially keystone trees. They provide shelter and habitat for one or more life cycle stages of moths and butterflies (Lepidoptera), and beneficial insects such as bumblebees, fireflies, and lacewings.

After feeding in the tree canopy, some caterpillars disperse from the tree to pupate in the ground or in leaf litter beneath it. If there's only compacted, regularly mowed turfgrass below, they have nowhere to go.

A soft landing provides caterpillars with the necessary refuge and habitat to pupate, while providing food and shelter for many other beneficial insects.

Soft landings concept developed by Heather Holm and Neighborhood Greening in consultation with Desiree Narango, Ph.D.

What a soft landing does

Provides beneficial insects a place to forage, shelter, and complete their life cycle.
Feeds birds — soft-bodied insects like caterpillars are the primary food source of most terrestrial birds.
Builds healthy soil through natural leaf litter and fibrous plant roots
Sequesters more carbon than turf grass
Reduces mowing

Io Moth Caterpillar Nancy Sabella Strasburg, VA

Photo from Anonymous | Strasburg, VA

623c94a7b5727f581f146775c0dca4d356e84a77

Photo (right side) from Michelle Detwiler | Penn Valley, PA.

What happens when caterpillars disperse from their host plant?

After feeding in the tree canopy, insects fall to the ground to pupate or overwinter. What they land in determines whether they survive.

Without a soft landing

Land on compacted turf
No cover or moisture
No food sources
Vulnerable to being mowed over
Less likely to survive

With a soft landing

Land on plants and native plants
Insulated, sheltered, protected from drying out
Food resources, including other invertebrates
Protected from mowing
More likely to complete their life cycle

Why a native tree

Not all trees are equal for wildlife. The majority of moths and butterflies are specialists and can only feed on one or a few native plants. Most non-native ornamental trees support very few.

Even among native trees, some support far more insect species than others. These are called keystone trees. Native oaks are the top keystone tree across the United States, as more than 940 types of caterpillars feed on oaks (Quercus). Native willows, cherries, pines, and poplars are also among the most productive keystone trees.

If you have a native tree, you already have the foundation. A soft landing transforms the ground beneath your native tree into a mini ecosystem—right in your own yard.

Don't have a native tree yet? Planting a keystone native tree is one of the highest-impact actions you can take to support moths and butterflies.

Find your keystones

How it all connects

This illustration shows how soft landings support insects, birds, and healthy soil, from the tree canopy to the ground beneath.

b90a5931a56d0530c0deb4b73eea8fa0470d810f (1)

Funded by a grant from Wild Ones Minnesota ©2021 Heather Holm and Neighborhood Greening;
Developed in consultation with Desiree Narango, Ph.D., Artwork by Elsa Cousins.
*For more on creating soft landing plantings under trees, visit: www.pollinatorsnativeplants.com/softlandings.html

How to plant a soft landing

1. Smother the turf — don't dig it.
Cardboard topped with wood chips works well, as does adding a thick layer of leaves. Instead of digging up turf, cover the grass and leave it for a season. This allows turf to break down naturally over time, lessening the risk of damaging the tree's root system. Keep woodchips thin over root zones and keep them entirely away from the trunk, as piled-up mulch against the bark traps moisture and invites rot. Pull any mulch back before you plant. Learn why leaving the leaves matters.

2. Stay three feet from the trunk.
Plant outside the root flare to protect the tree's primary roots. The plants will fill that gap as they establish.

3. Plant small and don’t raise the bed
Tree roots are concentrated in the top several inches of soil. To minimize root damage, use plugs or small cell-pack plants instead of larger plants, and a hand trowel instead of a shovel. Small, shallow holes let you tuck plants in around the roots instead of cutting through them.

Don't add soil or compost on top of the root zone, even to build a raised bed. It can suffocate the tree's roots. Instead, improve the soil naturally with leaf litter, bark, and small twigs.

Choosing plants for your soft landing

Native plants that thrive in both full sun and partially shaded habitats work best for a soft landing planting. The specific native plants depend on where you live.

For the Northeast, Upper Midwest, and northern Mid-Atlantic, Heather Holm and Neighborhood Greening have put together a soft landings-specific plant list and regional handout.

Outside that region, or if you want to explore more broadly, the HNP keystone plant tool covers the whole U.S. It's also a good place to start if you're choosing a keystone tree. Not all keystone plants are shade-tolerant, so check growing conditions for each plant.