Photographs by Sandie Parrott
A monarch butterfly and sphinx moth on ‘Black Knight’ butterfly bush.Natives for butterfly host plants and caterpillar food

To provide places for butterflies to lay eggs as well as food for the emerging caterpillars, choose butterfly host plants. And remember that the caterpillars will be doing some major eating on your host plants—it’s part of the process!

Common name	Botanical name	Butterflies attracted
Aster	Aster	Pearl crescent
Cherry	Prunus	Red-spotted purple, tiger swallowtail, spring azure
Dogwood	Cornus	Spring azure
Elm	Ulmus americana	Comma, question mark, mourning cloak
False nettle	Boehmeria cylindrica	Red admiral, question mark, comma, Milbert’s tortoiseshell
Grasses, sedges	various	Alfalfa sulphur, Eastern tailed-blue
Hackberry	Celtis occidentalis	Question mark, comma, hackberry butterfly, tawny emperor, mourning cloak
Highbush blueberry	Vaccinium corymbosum	Brown elfin
Leadplant	Amorpha canescens	Dogface, silver-spotted skipper
Milkweed	Asclepias	Monarch, queen
Nettle	Urtica dioica	Red admiral, question mark, comma, Milbert’s tortoiseshell
Oak	Quercus	Banded hairstreak
Paw Paw	Asimina triloba	Zebra swallowtail
Sneezeweed	Helenium autumnale	Dainty sulphur
Spicebush	Lindera benzoin	Spicebush swallowtail, tiger swallowtail
Sundial lupine	Lupinus perennis	Karner blue, silvery blue
Swamp thistle	Cirsium muticum	Painted lady
Turtlehead	Chelone glabra	Baltimore, buckeye
Vetch	Vicia	Alfalfa sulphur, Eastern tailed-blue
Violet	Viola	Great spangled fritillary, meadow fritillary
Willow	Salix	Viceroy, mourning cloak

 

Nectar-producing plants for butterfly food

To encourage butterflies to continually visit your garden, choose a variety of nectar-producing plants (for butterfly food) that produce blooming flowers throughout the season. Butterflies are most active in mid to late summer, so make sure you have plenty of flowers in bloom at that time.

	Common name	Botanical name
Spring	Black-eyed Susan	Rudbeckia hirta
	Columbine	Aquilegia canadensis
	Nodding wild onion	Allium cernuum
	Spicebush	Lindera benzoin
	Wild geranium	Geranium maculatum
Midsummer	Bee balm	Monarda didyma
	Bergamot	Monarda fistulosa
	Black-eyed Susan	Rudbeckia hirta
	Blazing star, dense	Liatris spicata
	Blazing star, rough	Liatris aspera
	Butterfly weed	Asclepias tuberosa
	Buttonbush	Cephalanthus occidentalis
	Coreopsis, tall	Coreopsis tripteris
	Dogbane	Apocynum
	Fleabane	Erigeron
	Horsemint	Monarda punctata
	Meadowsweet	Spiraea alba
	Michigan lily	Lilium michiganense
	Milkweed, common	Asclepias syriaca
	Milkweed, swamp	Asclepias incarnata
	New Jersey tea	Ceanothus americanus
	Pearly everlasting	Anaphalis margaritacea
	Sunflower, giant	Helianthus giganteus
	Swamp thistle	Cirsium muticum
	Virginia mountain mint	Pycnanthemum virginianum
	Yarrow	Achillea millefolium
Late summer	Aster, flat-topped	Aster umbellatus
	Aster, heath	Aster ericoides
	Aster, smooth	Aster laevis
	Aster, New England	Aster novae-angliae
	Beggarticks	Bidens aristosa
	Boneset	Eupatorium perfoliatum
	Goldenrod, Ohio	Solidago ohioensis
	Goldenrod, rigid	Solidago rigida
	Goldenrod, showy	Solidago speciosa
	Ironweed, tall	Vernonia gigantea
	Joe-Pye weed	Eupatorium maculatum
	Sneezeweed	Helenium autumnale
	Steeplebush	Spiraea tomentosa

 

Charts courtesy of Suzan Campbell, Conservation Associate, Michigan Natural Features Inventory, and formerly from the Belle Isle Nature Center

Milkweed is a nectar source for many butterflies and hummingbirds as well as a larval food for monarchs (the caterpillars only eat milkweed).

Photographs by Steven NikkilaRoots and branches: The connection

When a tree or shrub has roots residing in several properties, differing treatment in one section of the root zone might affect the plant’s entire crown or just one section. In some species, water moves from a given root along a certain path in the trunk to serve a particular branch. Root and branch are usually on the same side of the tree. In such “ring porous” species*, what happens to a given root affects a given branch. In other species, water follows a zig-zag or spiral pattern, so what comes from one root may serve various branches all over the crown.

This post oak lost most of its roots on one side as the hill was cut away preparatory to building a retaining wall. (Arrows mark clipped root ends.) It will almost certainly lose limbs on this side. Extra water for remaining roots, an arborist’s care, and pruning to remove dead wood are in order.

* Including American elm, arborvitae, black locust, catalpa, cherry, false cypress, hackberry, hickory, honeylocust, Kentucky coffee tree, many oaks, mulberry, persimmon, sassafras, walnut, white ash, and yellowwood.

Even large roots can regenerate. These are the roots of a dwarf weeping beech. In two places you can see where the roots grew back from cut ends after the plant was dug from the field for sale. Bury a root, kill a tree? Nope!

There’s oft-repeated advice about grade changes: Don’t put more than four inches of soil over tree roots. You’ll find it in Extension bulletins and gardening books. What you won’t find included is the basis for the advice. After much searching, I found the source and can assure you that in most cases, it doesn’t apply to what gardeners do.

The caution is based on grade changes at construction sites—large scale alteration of the entire root zone, executed with heavy equipment to spread and pack fill soil to builders’ and pavers’ specifications. By contrast, gardeners raise beds of loose soil, using a wheelbarrow and cover only portions of root systems. I’ve done it, dozens of times, and watched both the beds and trees closely, some for as many as 30 years. I’ve also interviewed professors of horticulture who have done the same in demonstration areas and we agree that loose soil over part of a root system, always kept away from the tree’s trunk, is no problem.

The same may apply to loose soil added over an entire root system. A team of University of California pathologists and Extension researchers filled over trees’ root systems with ten inches of soil in a test plot, settling that soil only with watering. In part of the field, tubing meant to bring oxygen into the soil was installed. The trees were sweet cherries, a species known to be intolerant of low soil oxygen situations. Yet “…no visible injury occurred. …no differences in plant growth, health or appearance…”

Gardener, bare that root ball!

Burlap and twine often remain intact and relatively strong for several years in-ground, repelling water and causing serious constriction to trunk and roots. Wire may persist for decades, partially or completely girdling first the flare roots and eventually the plant’s trunk. 

So remove these impediments and killers at planting time. Set the balled-and-burlapped tree or shrub in the planting hole and then remove all twine, rope, wire and burlap from at least the top half of the ball.

For more, check:

Chapter 7, “Planting” of Principles and Practice of Planting Trees and Shrubs by Gary W. Watson and E. B. Himelick, or www.isa-arbor.com/education/onlineResources/cad/resources/educ_CAD_BBTrees_View.pdf

 

Here are various species’ root fans I collected one day while transplanting, to illustrate colors, branching patterns and response to previous root pruning (branched tips). Webbed and netted around the ends of every root fan in good soil are mycorrhizal fungi—helper fungi—as much as 8,000 inches of fungal thread for every inch of root. Roots and fungi fill the soil spaces like water fills a sponge, and absorb water from the surface as readily as a sponge.

This spruce root begins a fall growth spurt, as evident in its pale, starch-thickened tip. Roots have a longer growing season than a plant’s aerial parts. They have a period of rapid expansion right after leafy growth begins in spring, and another lesser spurt in fall as leaves drop. Yet they grow all year-round, whenever the soil is above 40 degrees F and below about 85 degrees F. Thus any given root can add more length each year than a branch can. So if you want a tree or shrub to be all it can be, start by gauging the branch growth rate. If a limb extends itself 12 inches per year, plan to loosen soil and remove competition each year in a ring two- to three-feet out from the branch tips.