Why your trees need a soft landing this spring

We have many keystone trees in Manor Park such as sugar maples and oaks, but too many simply have grass under their canopy. According to entomologist Doug Tallamy, keystone trees are native tree species that support up to 90 percent of moths and butterflies which in turn support baby birds.

These beneficial insects also feed on keystone trees, complete part of their lifecycle in the trees, and then drop to the ground.

Soft landings are native plant gardens under trees that create critical habitats for moths and butterflies to survive. Oaks, maples, cherries, birches, poplars, and pines are especially important keystone trees. Plants, leaf litter, and even mulch under these trees offer shelter, habitat, or food.

By comparison, lawns do not support these insects and are harmful to trees.

Lawn is harmful for trees

Rich fungal life is one of the most important aspects of tree health. Arborist Dave Buttivant of Eastern Ontario Arborists and Treefeed says that soil health is key to tree health, “although you cannot see it, your trees and surrounding environment are only as healthy as the soils they grow in.”

Removing leaves and twigs from your lawn may be desirable for aesthetics, but decomposing organic matter provides nutrients for the trees and improves the soil’s fungal life. Compacted lawns also limit water and air flow into the soil.

Sheet mulching to create soft landings

To remove part of your lawn and create a soft landing, consider sheet mulching.

Lay cardboard on the grass and cover with mulch. Keep watered. Within a few weeks, you can easily plant through the cardboard and into the soil.

This method can temporarily affect water and air flow into the soil, but keeping the cardboard wet helps it to break down faster, minimizing this concern and giving you an almost instant new garden bed.

Before planting into your new garden, Dave suggests considering the soil. “Soil health can be easily amended to meet your tree’s needs . . . Deep root watering and fertilizing is a quick way to introduce essential nutrients, water and oxygen to your soils. Vertical mulching, aeration and mulch rings are a better long-term solution.”

Native shade plants

Many native plants thrive even in shady conditions throughout the spring, summer, and fall. Spring ephemerals are flowers that thrive under deciduous trees in the springtime before the trees leaf out. Many asters and goldenrods flower in shady conditions from late summer into November.

Dry shade plants include wild columbine, hairy beardtongue, heart leaf aster, zigzag goldenrod, and bottlebrush rye. These are available through A Cultivated Art in Vanier (www.acultivatedart.com) or online through Ontario Native Plants (onplants.ca). Shade plants requiring medium to moist soil are: foam flower, wood poppy, Virginia bluebells, wild geranium, woodland strawberry, and Ontario’s many trilliums. Both Ontario Natives and

Ritchie Feed and Seed’s newly expanded native plants section stock many of these perennials.

If you prefer the lawn look but want to better support your tree and wildlife, consider Pennsylvania sedge. When planted densely, this sedge creates a lush green carpet even under large tree canopies.

The new right of way by-laws allow citizens to have residential gardens in the right of way bordering their property. Plants are not allowed within one metre of a City of Ottawa tree trunk. However, mulch and leaf litter is allowed within a metre, and your soft-landing plants can be planted starting one metre away.

“The relationship between our manicured lawns and trees has always been greatly overlooked. Nowhere in our native forests do our trees have to compete with the greed, appetite and thirst of invasive turf grasses. Not only does turf outcompete our trees’ needs when it comes to nutrient availability and proper water uptake, but the mere sight of grass encourages foot traffic, gas equipment usage and extreme soil compaction. Without access to valuable fungi (mycorrhizae) and oxygen, a tree’s feeder roots are unable to access important nutrients such as nitrogen which encourages healthy green growth.”

Dave Buttivant of Eastern Ontario Arborists and Treefeed.ca

Reduced labour, more enjoyment

By having a soft landing underneath your tree, you’ll have a healthier tree and will be supporting local butterflies and moths. In addition, you’ll spend less time mowing, raking, weeding, and watering your lawn. Skip raking the leaves and the plant stalks in both spring and fall to further support wildlife and the fungal life of your tree’s soil, and to free up even more time for enjoying your garden.

Follow www.facebook.com/ManorParkEnviro for free mulch this spring!

This article was written by Chronicle gardning columnist Christina Keys.